51
|
Yang Y, Sun LT, Hu Q, Cao Y, Lu W, Feng YC, Fang X, Zhang XZ, Zhao HW, Xie DZ. Studies on low energy beam transport for high intensity high charged ions at IMP. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A719. [PMID: 24593453 DOI: 10.1063/1.4832935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) is an advanced fully superconducting ECR ion source at IMP designed to be operational at the microwave frequency of 18-24 GHz. The existing SECRAL beam transmission line is composed of a solenoid lens and a 110° analyzing magnet. Simulations of particle tracking with 3D space charge effect and realistic 3D magnetic fields through the line were performed using particle-in-cell code. The results of the beam dynamics show that such a low energy beam is very sensitive to the space charge effect and significantly suffers from the second-order aberration of the analyzing magnet resulting in large emittance. However, the second-order aberration could be reduced by adding compensating sextupole components in the beam line. On this basis, a new 110° analyzing magnet with relatively larger acceptance and smaller aberration is designed and will be used in the design of low energy beam transport line for a new superconducting ECR ion source SECRAL-II. The features of the analyzer and the corresponding beam trajectory calculation will be detailed and discussed in this paper.
Collapse
|
52
|
Sun L, Lu W, Feng YC, Zhang WH, Zhang XZ, Cao Y, Zhao YY, Wu W, Yang TJ, Zhao B, Zhao HW, Ma LZ, Xia JW, Xie D. Progress of superconducting electron cyclotron resonance ion sources at Institute of Modern Physics (IMP). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A942. [PMID: 24593521 DOI: 10.1063/1.4825164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Superconducting ECR ion sources can produce intense highly charged ion beams for the application in heavy ion accelerators. Superconducting Electron Resonance ion source with Advanced Design (SECRAL) is one of the few fully superconducting ECR ion sources that has been successfully built and put into routine operation for years. With enormous efforts and R&D work, promising results have been achieved with the ion source. Heated by the microwave power from a 7 kW/24 GHz gyrotron microwave generator, very intense highly charged gaseous ion beams have been produced, such as 455 eμA Xe(27+), 236 eμA Xe(30+), and 64 eμA Xe(35+). Since heavy metallic ion beams are being more and more attractive and important for many accelerator projects globally, intensive studies have been made to produce highly charged heavy metal ion beams, such as those from bismuth and uranium. Recently, 420 eμA Bi(30+) and 202 eμA U(33+) have been produced with SECRAL source. This paper will present the latest results with SECRAL, and the operation status will be discussed as well. An introduction of recently started SECRAL II project will also be given in the presentation.
Collapse
|
53
|
Hu T, Zhang XZ, Sun JM, Li HY, Fu JM. Leaf functional trait variation associated with salt tolerance in perennial ryegrass. PLANT BIOLOGY (STUTTGART, GERMANY) 2014; 16:107-116. [PMID: 23590346 DOI: 10.1111/plb.12012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 01/05/2013] [Indexed: 06/02/2023]
Abstract
Salinity is one of major environmental stresses that dramatically threaten plant growth, and variations in genetic structure and functional traits have important effects on the salt tolerance of perennial ryegrass (Lolium perenne L.). The objectives of this study were to: (i) assess the inter-clonal variation of functional traits of accessions among geographic groups or between wild and commercial groups in response to salt stress; (ii) develop a mathematical model to effectively assess salt tolerance of perennial ryegrass accessions originating from different geographic populations; and (iii) determine the relation between spatial genetic structure and salt tolerance in perennial ryegrass. Wide variations were found among the accessions for seven functional traits. One regression model (F = 0.49 × F1 + 0.303 × F2 + 0.207 × F3) was established to ascertain salt tolerance of each accession. The highest variation of the traits and salt tolerance were obtained for accessions from the European group. Wild accessions exhibited more variation in functional traits and salt tolerance than commercial cultivars. Both molecular marker techniques and functional traits were used to conduct phylogenetic analysis, and the majority of accessions from the same or adjacent regions were clustered into the same group or subgroup. The perennial ryegrass accessions with similar salt tolerance had a close phylogenetic background. The patterns in functional trait variations associated with salt tolerance might allow acceleration of the process for improving salt stress resistance in perennial ryegrass.
Collapse
|
54
|
Zhang XZ, Wang LL, Liu YQ. [Clinical observation on cervical headache treated with acupuncture and fire needling technique]. ZHONGGUO ZHEN JIU = CHINESE ACUPUNCTURE & MOXIBUSTION 2013; 33:989-992. [PMID: 24494285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To observe the efficacy in cervical headache of acupuncture combined with fire needling and the simple acupuncture therapy. METHODS One hundred and eighty cases were randomized into an acupuncture plus fire needling group (group A) and an acupuncture group (group B), 90 cases in each one. Baihui (GV 20), Wangu (GB 12), Fengchi (GB 20), Tianzhu (BL 10) and Neck-Jiaji (EX-B 2) were selected in the two groups. In group A, the fire needling technique was applied to all the above points before acupuncture with filiform needles. In group B, the acupuncture therapy was used only. The treatment was given once a day, the efficacy was compared between the two groups after 20 treatments. RESULTS The total effective rate was 95.6% (86/90) in group A and was 84. 4% (76/90) in group B, indicating the significant difference in comparison (P<0.05). VAS were 7.44+/-1.26 and 0.73+/-l. 44 before and after treatment in group A separately, those were 7.56+/-1.07 and 2. 56+/-2. 99 in group B, indicating the significant difference in comparison (P<0.01). The difference in VAS after treatment was significant between the two groups. In group A, the follow-up visit was conducted at 3 months and 6 months after treatment for the cured cases. The total recurrence rate in the patients without bony pathological changes was 14.8% (4/27) and that in the patients with bony pathological changes was 43. 5% (10/23), there was significant difference between them (P<0. 05). CONCLUSION The combined therapy of fire needling technique and filiform needle acupuncture improves the efficacy and sustains the efficacy especially on cervical headache without bony pathological changing.
Collapse
|
55
|
Yang Y, Zhang ZM, Wu Q, Zhang WH, Ma HY, Sun LT, Zhang XZ, Liu ZW, He Y, Zhao HW, Xie DZ. A low energy beam transport system for proton beam. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:033306. [PMID: 23556814 DOI: 10.1063/1.4796096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A low energy beam transport (LEBT) system has been built for a compact pulsed hadron source (CPHS) at Tsinghua University in China. The LEBT, consisting of two solenoids and three short-drift sections, transports a pulsed proton beam of 60 mA of energy of 50 keV to the entrance of a radio frequency quadrupole (RFQ). Measurement has shown a normalized RMS beam emittance less than 0.2 π mm mrad at the end of the LEBT. Beam simulations were carried out to compare with the measurement and are in good agreement. Based on the successful CPHS LEBT development, a new LEBT for a China ADS projector has been designed. The features of the new design, including a beam chopper and beam simulations of the LEBT are presented and discussed along with CPHS LEBT development in this article.
Collapse
|
56
|
Xu D, Wang LL, Zhang XZ, Wang J, Zang XN. Orthogonal analysis of elements affecting the formation of cystocarps on female gametophyte of Gracilariopsis lemaneiformis. COMMUNICATIONS IN AGRICULTURAL AND APPLIED BIOLOGICAL SCIENCES 2013; 78:493-495. [PMID: 25141750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
|
57
|
Wang LP, Zhang XZ, Guo J, Liu HL, Zhang Y, Liu CZ, Yi JH, Wang LP, Zhao JP, Li SS. Efficacy of acupuncture for acute migraine attack: a multicenter single blinded, randomized controlled trial. PAIN MEDICINE 2012; 13:623-30. [PMID: 22536889 DOI: 10.1111/j.1526-4637.2012.01376.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE We aim to investigate the efficacy of acupuncture for acute migraine attacks comparing with sham acupuncture. DESIGN The study was designed as a multicenter, single-blinded, randomized controlled clinical trial. SETTING AND PATIENTS From March 2007 to February 2009, 150 patients were randomly allocated to verum or sham acupuncture group in a ratio of 1:1. INTERVENTIONS Every patient received a verum or sham acupuncture treatment when having a migraine attack and, medications were allowed if the pain failed to be relieved two hours after the acupuncture. OUTCOME MEASURES The primary outcome was visual analog scale (VAS) scores for pain, ranging from 0 (no pain) to 10 (worst pain ever). RESULTS The mean VAS scores 24 hours after treatment decreased from 5.7 ± 1.4 to 3.3 ± 2.5 in the verum acupuncture group, and from 5.4 ± 1.3 to 4.7 ± 2.4 in the sham acupuncture group. Significant differences existed between the two groups (P = 0.001). CONCLUSIONS This trial suggested that verum acupuncture group was superior to sham acupuncture group on relieving pain and reducing the usage of acute medication.
Collapse
|
58
|
Zhao HW, Lu W, Zhang XZ, Feng YC, Guo JW, Cao Y, Li JY, Guo XH, Sha S, Sun LT, Xie DZ. Performance and operation of advanced superconducting electron cyclotron resonance ion source SECRAL at 24 GHz. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:02A320. [PMID: 22380167 DOI: 10.1063/1.3666913] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
SECRAL (superconducting ECR ion source with advanced design in Lanzhou) ion source has been in routine operation for Heavy Ion Research Facility in Lanzhou (HIRFL) accelerator complex since May 2007. To further enhance the SECRAL performance in order to satisfy the increasing demand for intensive highly charged ion beams, 3-5 kW high power 24 GHz single frequency and 24 GHz +18 GHz double frequency with an aluminum plasma chamber were tested, and some exciting results were produced with quite a few new record highly charged ion beam intensities, such as (129)Xe(35+) of 64 eμA, (129)Xe(42+) of 3 eμA, (209)Bi(41+) of 50 eμA, (209)Bi(50+) of 4.3 eμA and (209)Bi(54+) of 0.2 eμA. In most cases SECRAL is operated at 18 GHz to deliver highly charged heavy ion beams for the HIRFL accelerator, only for those very high charge states and very heavy ion beams such as (209)Bi(36+) and (209)Bi(41+), SECRAL has been operated at 24 GHz. The total operation beam time provided by SECRAL up to July 2011 has exceeded 7720 hours. In this paper, the latest performance, development, and operation status of SECRAL ion source are presented. The latest results and reliable long-term operation for the HIRFL accelerator have demonstrated that SECRAL performance for production of highly charged heavy ion beams remains improving at higher RF power with optimized tuning.
Collapse
|
59
|
Lu W, Xie DZ, Zhang XZ, Xiong B, Ruan L, Sha S, Zhang WH, Cao Y, Lin SH, Guo JW, Fang X, Guo XH, Li XX, Ma HY, Yang Y, Wu Q, Zhao HY, Ma BH, Wang H, Zhu YH, Feng YC, Li JY, Li JQ, Sun LT, Zhao HW. Development of DRAGON electron cyclotron resonance ion source at Institute of Modern Physics. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:02A328. [PMID: 22380175 DOI: 10.1063/1.3669800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A new room temperature electron cyclotron resonance (ECR) ion source, DRAGON, is under construction at IMP. DRAGON is designed to operate at microwaves of frequencies of 14.5-18 GHz. Its axial solenoid coils are cooled with evaporative medium to provide an axial magnetic mirror field of 2.5 T at the injection and 1.4 T at the extraction, respectively. In comparison to other conventional room temperature ECR ion sources, DRAGON has so far the largest bore plasma chamber of inner diameter of 126 mm with maximum radial fields of 1.4-1.5 T produced by a non-Halbach permanent sextupole magnet.
Collapse
|
60
|
Sha S, Zhao HW, Guo XH, Zhang ZL, Fang X, Guo JW, Zhang WH, Lu W, Cao Y, Ma HY, Lin SH, Li XX, Ma BH, Yang Y, Wang H, Wu Q, Li JY, Feng YC, Zhao HY, Zhu YH, Sun LT, Zhang XZ, Chen XM, Xie DZ. Status of the laser ion source at IMP. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:02B303. [PMID: 22380282 DOI: 10.1063/1.3656391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A laser (Nd:YAG laser, 3 J, 1064 nm, 8-10 ns) ion source has been built and under development at IMP to provide pulsed high-charge-state heavy ion beams to a radio frequency quadrupole (RFQ) for upgrading the IMP accelerators with a new low-energy beam injector. The laser ion source currently operates in a direct plasma injection scheme to inject the high charge state ions produced from a solid target into the RFQ. The maximum power density on the target was about 8.4 × 10(12) W∕cm(2). The preliminary experimental results will be presented and discussed in this paper.
Collapse
|
61
|
Zhang WH, Ma HY, Yang Y, Wu Q, Zhang XZ, Wang H, Ma BH, Feng YC, Fang X, Guo JW, Cao Y, Li XX, Zhu YH, Li JY, Sha S, Lu W, Lin SH, Guo XH, Zhao HY, Sun LT, Xie DZ, Peng SX, Liu ZW, Zhao HW. A 2.45 GHz electron cyclotron resonance proton ion source and a dual-lens low energy beam transport. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:02A329. [PMID: 22380176 DOI: 10.1063/1.3669802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The structure and preliminary commissioning results of a new 2.45 GHz ECR proton ion source and a dual-lens low energy beam transport (LEBT) system are presented in this paper. The main magnetic field of the ion source is provided by a set of permanent magnets with two small electro-solenoid magnets at the injection and the extraction to fine tune the magnetic field for better microwave coupling. A 50 keV pulsed proton beam extracted by a three-electrode mechanism passes through the LEBT system of length of 1183 mm. This LEBT consists of a diagnosis chamber, two Glaser lenses, two steering magnets, and a final beam defining cone. A set of inner permanent magnetic rings is embedded in each of the two Glaser lenses to produce a flatter axial-field to reduce the lens aberrations.
Collapse
|
62
|
Cao Y, Lu W, Zhang WH, Sha S, Yang Y, Ma BH, Wang H, Zhu YH, Guo JW, Fang X, Lin SH, Li XX, Feng YC, Li JY, Zhao HY, Ma HY, Zhang XZ, Guo XH, Wu Q, Sun LT, Zhao HW, Xie DZ. Study of ion beam transport from the SECRAL electron cyclotron resonance ion source at the Institute of Modern Physics. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:02B726. [PMID: 22380331 DOI: 10.1063/1.3680545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Ion beam transport from the Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) electron cyclotron resonance ion source was studied at the Institute of Modern Physics during 2010. Particle-in-cell simulations and experimental results have shown that both space charge and magnetic aberrations lead to a larger beam envelope and emittance growth. In the existing SECRAL extraction beam line, it has been shown that raising the solenoid lens magnetic field reduces aberrations in the subsequent dipole and results in lower emittance. Detailed beam emittance measurements are presented in this paper.
Collapse
|
63
|
Zhang XZ, Wu ZH, Yang SP, Pang HY, Jian JC, Lu YS. Expression pattern of heat-shock cognate 70 gene of humphead snapper, Lutjanus sanguineus (Cuvier), infected by Vibrio harveyi. JOURNAL OF FISH DISEASES 2011; 34:719-729. [PMID: 21883283 DOI: 10.1111/j.1365-2761.2011.01288.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The heat-shock cognate 70 (HSC70) gene of humphead snapper, Lutjanus sanguineus, designated as ByHSC70, was cloned by rapid amplification of cDNA ends (RACE) with the primers designed from the known expressed sequence tag (EST) identified from the subtracted cDNA library of the head kidney of humphead snapper. The full-length cDNA of ByHSC70 is 2313 bp, containing a 5' terminal untranslated region (UTR) of 96 bp, a 3' terminal UTR of 267 bp, and an open reading frame (ORF) of 1950 bp encoding a polypeptide of 650 amino acids with a theoretical molecular weight of 71.21 kDa and an estimated isoelectric point (pI) of 5.08. ByHSC70 contained three classical HSP70 family signatures. BLAST analysis showed that the amino acid sequence of ByHSC70 had the highest similarity of 99% when compared with other HSC70s. Fluorescent real-time quantitative RT-PCR was used to examine the expression of ByHSC70 gene in eight kinds of tissues/organs of humphead snapper after challenge with Vibrio harveyi. There was a clear time-dependent expression pattern of ByHSC70 in head kidney, spleen and thymus after bacterial challenge, and the expression of mRNA reached a maximum level at 9, 6 and 24 h post-infection and then returned to control levels after 15, 24 and 36 h, respectively. Our results suggest that HSC70 is an important component in the immune system of humphead snapper, its their rapid transcriptional upregulation in response to V. harveyi infection might be important for survival of humphead snapper.
Collapse
|
64
|
Zhang XZ, Dai LP, Wu ZH, Jian JC, Lu YS. Expression pattern of heat shock protein 90 gene of humphead snapper Lutjanus sanguineus during pathogenic Vibrio harveyi stress. JOURNAL OF FISH BIOLOGY 2011; 79:178-193. [PMID: 21722118 DOI: 10.1111/j.1095-8649.2011.03012.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The full-length cDNA of heat shock protein 90 (HSP90) of humphead snapper Lutjanus sanguineus, designated as rsHSP90, was cloned by rapid amplification of complementary (c)DNA ends (RACE) techniques with the primers designed from the known expressed sequence tag (EST) sequence identified from the subtracted cDNA library of the head kidney of L. sanguineus. Sequence analysis showed that the full-length cDNA of rsHSP90 was 2745 bp, containing a 5' terminal untranslated region (UTR) of 99 bp, a 3' terminal UTR of 471 bp and an open reading frame (ORF) of 2175 bp encoding a polypeptide of 725 amino acids. On the basis of the deduced amino acid sequence, the theoretical molecular mass of rsHSP90 was calculated to be 83·18 kDa with an isoelectric point of 4·79. Moreover, five classical HSP90 family signatures were found in the amino acids sequence of rsHSP90 by PredictProtein. Basic local-alignment search-tool (BLAST) analysis revealed that the amino acids sequence of rsHSP90 had the highest similarity of 97% when compared with other HSP90s. Fluorescent real-time quantitative reverse-transcription (RT)-PCR was used to examine the expression pattern of rsHSP90 in eight kinds of tissues and organs of L. sanguineus challenged with Vibrio harveyi. There was a clear time-dependent expression pattern of rsHSP90 in head kidney, spleen and thymus after bacterial challenge and the expression of messenger (m)RNA reached the maximum level at the time points of 9, 15 and 24 h, respectively. The up-regulated mRNA expression of rsHSP90 in L. sanguineus after bacterial challenge indicated that rsHSP90 was inducible and might be involved in immune response.
Collapse
|
65
|
Wu JM, Xu YY, Li ZH, Yuan XY, Wang PF, Zhang XZ, Liu YQ, Guan J, Guo Y, Li RX, Zhang H. Heparin-functionalized collagen matrices with controlled release of basic fibroblast growth factor. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:107-114. [PMID: 21052795 DOI: 10.1007/s10856-010-4176-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Accepted: 10/23/2010] [Indexed: 05/30/2023]
Abstract
Tissue engineering scaffolds with controlled long-term release of growth factors are constructed in an attempt to mimic the intelligent ability of the extracellular matrix (ECM) to release endogenous growth factors. In this study, collagen sponges (Collagen group) were modified by N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) crosslinking (EDC/NHS group) and heparin immobilization (EDC/NHS-H group), and subsequently seeded with human umbilical vein endothelial cells (HUVECs). Native and modified sponges were pre-adsorbed with basic fibroblast growth factor (bFGF) to evaluate the sustained release and bioactive maintenance of bFGF from the sponges. We found that modified collagen matrices permitted HUVECs to proliferate and migrate well and to distribute uniformly. The EDC/NHS-H group exhibited an excellent sustained-release profile and bioactive maintenance of the pre-adsorbed bFGF as compared with the Collagen and EDC/NHS groups. These results suggest that heparin-functionalized collagen matrices can support a controlled release of bFGF and thus, have potential as a tissue engineering scaffold.
Collapse
|
66
|
Zhang XZ, Xu ZJ, Tai RZ, Zhen XJ, Wang Y, Guo Z, Yan R, Chang R, Wang B, Li M, Zhao J, Gao F. Ratio-contrast imaging of dual-energy absorption for element mapping with a scanning transmission X-ray microscope. JOURNAL OF SYNCHROTRON RADIATION 2010; 17:804-809. [PMID: 20975228 DOI: 10.1107/s0909049510031250] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Accepted: 08/04/2010] [Indexed: 05/30/2023]
Abstract
The detection of chemical mapping with a spatial resolution of 30 nm has been achieved with a scanning transmission X-ray microscope at the Shanghai Synchrotron Radiation Facility. For each specimen, two absorption images were scanned separately with energies E(1) and E(2): E(1) was focused on the absorption edge of the chosen element and E(2) was focused below the edge. A K-edge division method is proposed and applied to obtain the element mapping. Compared with the frequently used K-edge subtraction method, this ratio-contrast method is shown to be more accurate and sensitive in identifying the elements of interest, where the definition of the contrast threshold is simple and clear in physics. Several examples are presented to illustrate the effectiveness of the method.
Collapse
|
67
|
Bai CL, Zhang HQ, Sagawa H, Zhang XZ, Colò G, Xu FR. Effect of the tensor force on the charge exchange spin-dipole excitations of 208Pb. PHYSICAL REVIEW LETTERS 2010; 105:072501. [PMID: 20868034 DOI: 10.1103/physrevlett.105.072501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Indexed: 05/29/2023]
Abstract
The charge exchange spin-dipole (SD) excitations of 208Pb are studied by using a fully self-consistent Skyrme Hartree-Fock plus random phase approximation formalism which includes the tensor interaction. It is found, for the first time, that the tensor correlations have a unique, multipole-dependent effect on the SD excitations; that is, they produce a softening of 1{-} states, but a hardening of 0{-} and 2{-} states. This paves the way to a clear assessment of the strength of the tensor terms. We compare our results with a recent measurement, showing that our choice of tensor terms improves the agreement with experiment. The robustness of our results is supported by the analytic form of the tensor matrix elements.
Collapse
|
68
|
Zhao HW, Sun LT, Lu W, Zhang XZ, Guo XH, Cao Y, Zhao HY, Feng YC, Li JY, Ma HY, Shang Y, Ma BH, Wang H, Li XX, Xie DZ. New development of advanced superconducting electron cyclotron resonance ion source SECRAL (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:02A202. [PMID: 20192321 DOI: 10.1063/1.3273058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Superconducting electron cyclotron resonance ion source with advance design in Lanzhou (SECRAL) is an 18-28 GHz fully superconducting electron cyclotron resonance (ECR) ion source dedicated for highly charged heavy ion beam production. SECRAL, with an innovative superconducting magnet structure of solenoid-inside-sextupole and at lower frequency and lower rf power operation, may open a new way for developing compact and reliable high performance superconducting ECR ion source. One of the recent highlights achieved at SECRAL is that some new record beam currents for very high charge states were produced by 18 GHz or 18+14.5 GHz double frequency heating, such as 1 e microA of (129)Xe(43+), 22 e microA of (209)Bi(41+), and 1.5 e microA of (209)Bi(50+). To further enhance the performance of SECRAL, a 24 GHz/7 kW gyrotron microwave generator was installed and SECRAL was tested at 24 GHz. Some promising and exciting results at 24 GHz with new record highly charged ion beam intensities were produced, such as 455 e microA of (129)Xe(27+) and 152 e microA of (129)Xe(30+), although the commissioning time was limited within 3-4 weeks and rf power only 3-4 kW. Bremsstrahlung measurements at 24 GHz show that x-ray is much stronger with higher rf frequency, higher rf power. and higher minimum mirror magnetic field (minimum B). Preliminary emittance measurements indicate that SECRAL emittance at 24 GHz is slightly higher that at 18 GHz. SECRAL has been put into routine operation at 18 GHz for heavy ion research facility in Lanzhou (HIRFL) accelerator complex since May 2007. The total operation beam time from SECRAL for HIRFL accelerator has been more than 2000 h, and (129)Xe(27+), (78)Kr(19+), (209)Bi(31+), and (58)Ni(19+) beams were delivered. All of these new developments, the latest results, and long-term operation for the accelerator have again demonstrated that SECRAL is one of the best in the performance of ECR ion source for highly charged heavy ion beam production. Finally the future development of SECRAL will be presented.
Collapse
|
69
|
Sun LT, Zhao HW, Lu W, Zhang XZ, Feng YC, Li JY, Cao Y, Guo XH, Ma HY, Zhao HY, Shang Y, Ma BH, Wang H, Li XX, Jin T, Xie DZ. Production of highly charged ion beams with SECRAL. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:02A318. [PMID: 20192339 DOI: 10.1063/1.3267306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL) is an all-superconducting-magnet electron cyclotron resonance ion source (ECRIS) for the production of intense highly charged ion beams to meet the requirements of the Heavy Ion Research Facility in Lanzhou (HIRFL). To further enhance the performance of SECRAL, an aluminum chamber has been installed inside a 1.5 mm thick Ta liner used for the reduction of x-ray irradiation at the high voltage insulator. With double-frequency (18+14.5 GHz) heating and at maximum total microwave power of 2.0 kW, SECRAL has successfully produced quite a few very highly charged Xe ion beams, such as 10 e microA of Xe(37+), 1 e microA of Xe(43+), and 0.16 e microA of Ne-like Xe(44+). To further explore the capability of the SECRAL in the production of highly charged heavy metal ion beams, a first test run on bismuth has been carried out recently. The main goal is to produce an intense Bi(31+) beam for HIRFL accelerator and to have a feel how well the SECRAL can do in the production of very highly charged Bi beams. During the test, though at microwave power less than 3 kW, more than 150 e microA of Bi(31+), 22 e microA of Bi(41+), and 1.5 e microA of Bi(50+) have been produced. All of these results have again demonstrated the great capability of the SECRAL source. This article will present the detailed results and brief discussions to the production of highly charged ion beams with SECRAL.
Collapse
|
70
|
Xu HJ, Zhu HC, Shan XD, Liu YX, Gao JY, Zhang XZ, Zhang JM, Wang PW, Hou YM, Yu DP. Effects of annealing on the ferromagnetism and photoluminescence of Cu-doped ZnO nanowires. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:016002. [PMID: 21386237 DOI: 10.1088/0953-8984/22/1/016002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Room temperature ferromagnetic Cu-doped ZnO nanowires have been synthesized using the chemical vapor deposition method. By combining structural characterizations and comparative annealing experiments, it has been found that both extrinsic (CuO nanoparticles) and intrinsic (Zn(1-x)Cu(x)O nanowires) sources are responsible for the observed ferromagnetic ordering of the as-grown samples. As regards the former, annealing in Zn vapor led to a dramatic decrease of the ferromagnetism. For the latter, a reversible switching of the ferromagnetism was observed with sequential annealings in Zn vapor and oxygen ambience respectively, which agreed well with previous reports for Cu-doped ZnO films. In addition, we have for the first time observed low temperature photoluminescence changed with magnetic properties upon annealing in different conditions, which revealed the crucial role played by interstitial zinc in directly mediating high T(c) ferromagnetism and indirectly modulating the Cu-related structured green emission via different charge transfer transitions.
Collapse
|
71
|
Zhang XZ, Wang RM, Qian J. [Observation on therapeutic effects of different treatments for sudden deafness]. ZHONGGUO ZHEN JIU = CHINESE ACUPUNCTURE & MOXIBUSTION 2009; 29:525-528. [PMID: 19835117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To search for the best acupuncture treatment for sudden sensorineural deafness. METHODS One hundred and eighty-seven patients were randomly divided into an acupuncture group (group A), an electroacupuncture group (group B), an acupuncture pius acupoint injection group (group C), an electroacupuncture plus acupoint injection group (group D). Ermen (TE 21), Tinggong (SI 19), Tinghui (GB 2), Yifeng (TE 17), Fengchi (GB 20) on the affected side, and Shangxing (GV 23), Baihui (GV 20), Sishencong (EX-HN 1), Hegu (LI 4), Waiguan (TE 5), etc. were selected. The treatment was given once each day. Hearing was tested after treatment for 40 sessions and the therapeutic effects were compared. RESULTS The total effective rate was 47.6% in the group A, 79.2% in the group B, 76.0% in the group C and 94.0% in the group D, the group D being the best and the group A being the worst, and with significant differences between the group D and the other groups (all P < 0.05). In the group D, the therapeutic effect for patients who received the treatment within 2 weeks after attack were superior to those who received the treatment over 2 weeks after attack (P < 0.05); the acupuncture therapeutic effect for the mild and moderate patients was superior to that of severe patients (P < 0.05); the acupuncture therapeutic effect for the patients less than 50 years old was superior to those more than 50 years old (P < 0.05). CONCLUSION Electroacupuncture plus acupoint injection is the heat therapy for sudden sensorineural deafness, and the timely intervention of acupuncture, the severity degree of the illness and the patient's age are all related to the prognosis of this disease.
Collapse
|
72
|
Wei JH, Leng CJ, Zhang XZ, Li WH, Liu ZY, Shi J. Synthesis and magnetorheological effect of Fe3O4-TiO2nanocomposite. ACTA ACUST UNITED AC 2009. [DOI: 10.1088/1742-6596/149/1/012083] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
73
|
|
74
|
Wang BQ, Zhang XZ, Xia CH, Zhang XJ, Xu J, Wang PW, Fu HG, Jing LQ, Yu DP. Fabrication of oriented ZnO nanorod arrays and their optical performances. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:1113-1118. [PMID: 19441467 DOI: 10.1166/jnn.2009.c099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The well-aligned ZnO nanorod arrays were fabricated through a simple chemical process under low temperature. The nanorod arrays were characterized by XRD, SEM, TEM, HRTEM and SAED, and their optical performances were investigated with Raman and PL spectroscopy. The results show that the as-prepared ZnO nanorod arrays are dense, the individual ZnO nanorod is hexagonal shape and grows along c-axis perpendicular to the substrate surface with good single crystal in nature. The Raman property of nanorod arrays displays change with the altering the preparation conditions. Moreover, the PL performances of ZnO nanorod arrays exhibit tunable character with adjusting the synthesis conditions.
Collapse
|
75
|
Zhao HW, Sun LT, Zhang XZ, Guo XH, Cao Y, Lu W, Zhang ZM, Yuan P, Song MT, Zhao HY, Jin T, Shang Y, Zhan WL, Wei BW, Xie DZ. Intense beam production of highly charged heavy ions by the superconducting electron cyclotron resonance ion source SECRAL. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:02A315. [PMID: 18315105 DOI: 10.1063/1.2804900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
There has been increasing demand to provide higher beam intensity and high enough beam energy for heavy ion accelerator and some other applications, which has driven electron cyclotron resonance (ECR) ion source to produce higher charge state ions with higher beam intensity. One of development trends for highly charged ECR ion source is to build new generation ECR sources by utilization of superconducting magnet technology. SECRAL (superconducting ECR ion source with advanced design in Lanzhou) was successfully built to produce intense beams of highly charged ion for Heavy Ion Research Facility in Lanzhou (HIRFL). The ion source has been optimized to be operated at 28 GHz for its maximum performance. The superconducting magnet confinement configuration of the ion source consists of three axial solenoid coils and six sextupole coils with a cold iron structure as field booster and clamping. An innovative design of SECRAL is that the three axial solenoid coils are located inside of the sextupole bore in order to reduce the interaction forces between the sextupole coils and the solenoid coils. For 28 GHz operation, the magnet assembly can produce peak mirror fields on axis of 3.6 T at injection, 2.2 T at extraction, and a radial sextupole field of 2.0 T at plasma chamber wall. During the commissioning phase at 18 GHz with a stainless steel chamber, tests with various gases and some metals have been conducted with microwave power less than 3.5 kW by two 18 GHz rf generators. It demonstrates the performance is very promising. Some record ion beam intensities have been produced, for instance, 810 e microA of O(7+), 505 e microA of Xe(20+), 306 e microA of Xe(27+), and so on. The effect of the magnetic field configuration on the ion source performance has been studied experimentally. SECRAL has been put into operation to provide highly charged ion beams for HIRFL facility since May 2007.
Collapse
|