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Osmotic Regulation of Betaine Content in Leymus chinensis Under Saline-alkali Stress and Cloning and Expression of Betaine Aldehyde Dehydrogenase(BADH) Gene

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Chemical Research in Chinese Universities 2008年第2期24卷 204-209页

作者： CUI Xi-yan WANG yong GUO ji-xun Key Laboratory for Vegetation Ecology of Ministry of Education Institute of Grassland Science Northeast Normal University Changchun 130024 P. R. China School of Life Sciences Jilin Agricultural University Changchun 130118 P. R. China

The potted Leymus chinensis seedlings were treated with saline-alkali solution of six different（from Ⅰ to Ⅵ） concentrations. The results demonstrate that the betaine content and Betaine-aldehyde dehydrogenase（BADH： EC 1.***.1.8） activities have a direct relation with increased stressing time in the same treatment; both exhibit a single peak with increasing the concentration of saline-alkali solution, and number V shows the highest value. The BADH gene of Leyrnus chinensis was cloned by RT-PCR and RACE technology and was designated as LcBADH. The cDNA sequence of LcBADH was 1774bp including the open reading frame（ORF） of 1521bp（coding 506 amino acids）. The vector of prokaryotic expression was constructed by inserting the LcBADH gene fragmcnt into pET30a（＋） and transformed into E. coli BL21（DE3）. The result of SDS-PAGE shows that the idio-protein with a molecular mass of 56.78 kDa was effectively expressed in the recombinant bacteria induced by isopropyl fl-D-thiogalactoside（IPTG）.

关键词： Leymus chinensis Saline-alkali stress BADH RACE Cloning and expression

Design for Isothermal Forging of Ti-46.5Al-2.5V-1.0Cr-0.3Ni Alloy

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Journal of Iron and Steel Research International 2010年第8期17卷 67-73页

作者： SI jia-yong HAN Peng-biao ZHANG ji Institute of Processing Technologies of Materials Central South University of Forestry and TechnologyChangsha 410004HunanChina High Temperature Material Research Division Central Iron andSteel Research InstituteBeijing 100081China

The three-dimensional finite element method was utilized to investigate the isothermal forging of Ti-46.5Al-2.5V-1.0Cr-0.3Ni（atomic percent,%）*** partition of height reduction,effective strain,and damage of the alloy during the forging were *** simulation results were verified by *** results show that large plastic deformation can improve the homogeneity of the deformed microstructure and the higher accumulative height reduction can be achieved through two-step *** the isothermal forging of two-step reduction of 60%＋62.5%（total height reduction of 85%）,the entire forged pancake can acquire refined microstructure and expand the uniform flow zone to almost the entire volume.

关键词： titanium aluminide isothermal forging multistep forging FEM simulation

Investigation into Hydrogen Diffusion and Susceptibility of Hydrogen Embrittlement of High Strength 0Cr16Ni5Mo Steel

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Journal of Iron and Steel Research International 2015年第10期22卷 961-968页

作者： yong-wei SUN ji-zhi CHEN Jun LIU College of Materials Science and Chemical Engineering Harbin Engineering University Luoyang Ship Material Research Institute

High strength bolt steel 0Crl6Ni5Mo was charged with hydrogen by means of electrochemical technique to evaluate the hydrogen diffusion behavior. The bolt steels were investigated by a combination of electrochemical hydrogen permeation, thermal desorption spectroscopy （TDS）, slow strain rate test （SSRT） and microstructure observation. The hydrogen concentration of both 10.9 grade （Rm=950-1 150 MPa） and 12.9 grade （Rm=1 150-1 250 MPa） bolt steels increases with increasing the hydrogen charging current densities and charging time. The 12.9 grade bolt steel has higher apparent diffusion coefficient than 10.9 grade steel, corresponding to the value of 4.7×10 7 mm^2/s. By means of TDS tests, the activation energies of the two experimental steels are 17.74 kJ/mol and 18.92 kJ/mol, respectively. The hydrogen traps of both grade bolt steels are dislocations and crystal lattice. The notch tensile strength of the steels is reduced with the hydrogen concentration carried out by SSRT. The fracture morphologies of the steels after hydrogen charging present ductile dimple and quasi-cleavage characteristic.

关键词： 0Cr16Ni5Mo steel hydrogen diffusion hydrogen permeation thermal desorption spectroscopy slow strain rate test

Clinical and pathological differences between serum immunoglobulin G4-positive and -negative type 1 autoimmune pancreatitis

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World Journal of Gastroenterology 2013年第25期19卷 4031-4038页

作者： woo Hyun Paik ji Kon Ryu jin Myung Park Byeong Jun Song Joo Kyung Park yong-Tae Kim Kyoungbun Lee Department of Internal Medicine Liver Research Institute Division of Gastroenterology Department of Internal Medicine Seoul National University College of Medicine Department of Pathology Seoul National University College of Medicine

AIM: To identify clinical and pathological differences between serum immunoglobulin G4 (IgG4)-positive (SIP) and IgG4-negative (SIN) type 1 autoimmune pancreatitis (AIP) in South Korea. METHODS: AIP was diagnosed by the international consensus diagnostic criteria. The medical records and pathology were retrospectively reviewed and IgG4-positive cells were counted in a high power field (HPF). Type I AIP was defined as a high serum level of IgG4or histological finding. SIN type 1 AIP was defined as a histological evidence of type 1 AIP and a normal serum IgG4 level. The clinical and pathological findings were compared between the two groups. The analysis was performed using Student's t test, Fischer's exact test and Mann-Whitney's U test. A P value of < 0.05 was considered statistically significant. As repeated com- parison was made, P values of less than 5% (P < 0.05) were considered significant. RESULTS: Twenty five patients with definite type 1 AIP (19 histologically and six serologically diagnosed cases) were enrolled. The mean tissue IgG4 concentrations were significantly higher in SIP than SIN group (40 cells per HPF vs 18 cells per HPF, P = 0.02). Among eight SIN patients, the tissue IgG4 concentrations were less than 15 cells per HPF in most of cases, except one. The sensitivity of serum IgG4 was 68% (17 SIP and eight SIN AIP). Other organ involvement was more frequent- ly associated with SIP than SIN AIP (59% vs 26%, P = 0.016). However, the relapse rate and diffuse swelling of the pancreas were not associated with serum IgG4 level. The concentrations of IgG4-positive cells per HPF were higher in SIP than SIN AIP (40 vs 18, P = 0.02). CONCLUSION: The sensitivity of serum IgG4 was 68% in type 1 AIP. High serum IgG4 level was associated with other organ involvement and tissue IgG4 concentration but did not affect the relapse rate in type 1 AIP.

关键词： Autoimmunity Chronic pancreatitis Immunoglobulin G4-related systemic disease Lymphoplas-macytic sclerosing pancreatitis Immunoglobulin G4

Variable selection via generalized SELO-penalized linear regression models

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 145-162页

作者： SHI Yue-yong CAO yong-xiu YU ji-chang jiAO Yu-ling School of Econoraics and Management China University of GeosciencesWuhan 430074China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073China Center for Resources and Environmental Economic Research China University of GeosciencesWuhan 430074China

The seamless-L0 （SELO） penalty is a smooth function on [0, ∞） that very closely resembles the L0 penalty, which has been demonstrated theoretically and practically to be effective in nonconvex penalization for variable selection. In this paper, we first generalize SELO to a class of penalties retaining good features of SELO, and then propose variable selection and estimation in linear models using the proposed generalized SELO （GSELO） penalized least squares （PLS） approach. We show that the GSELO-PLS procedure possesses the oracle property and consistently selects the true model under some regularity conditions in the presence of a diverging number of variables. The entire path of GSELO-PLS estimates can be efficiently computed through a smoothing quasi-Newton （SQN） method. A modified BIC coupled with a continuation strategy is developed to select the optimal tuning parameter. Simulation studies and analysis of a clinical data are carried out to evaluate the finite sample performance of the proposed method. In addition, numerical experiments involving simulation studies and analysis of a microarray data are also conducted for GSELO-PLS in the high-dimensional settings.

关键词： continuation coordinate descent BIC LLA oracle property SELO smoothing quasi-Newton

Mechanical and electrical properties of In-Bi solder at Bi_(2212) superconductor interface with annealed Ag spray layers and Ag precoating layers

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中国有色金属学会会刊：英文版 2009年第4期19卷 961-964页

作者： Seung-yong SHIN ji-Hyun LEE Hai-woong PARK Department of Materials Engineering Korea University of Technology and Education(KUT)

The electrical properties of solder contact layers between Cu-Ni shunt metal and tube type Bi2212 superconductor that is applied in superconducting fault current limiter were *** contact properties of the solders are improved not only by Ag precoating layers,but also by the pre-sprayed Ag layer and subsequent Ag precoating *** annealed Ag sprayed layers onto Bi2212 superconductor prior to Ag electroplating work as protecting layers for the superconductor from plating *** contact angle of the electroplated Ag layer is 42.91° and decreases to 15.25° and 5.88° with Ag sprayed layer and additional Ag electroplated *** Ag sprayed layer with suitable annealing prior to Ag electroplating improves contact strength of the Ag electroplated layer by about 12% due to denser microstructure of the Ag electroplated layers.

关键词：超导故障限流器 Bi2212 电镀银电气性能喷涂层预涂层退火焊料

Electroless deposition of Ni on template of halloysite and its magnetic property

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中国有色金属学会会刊：英文版 2004年第z1期14卷 152-156页

作者： FU Yu-bin ZHANG Li-de ZHENG ji-yong Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China Luoyang Ship Material Research Institute Luoyang 471039 China Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China Luoyang Ship Material Research Institute Luoyang 471039 China

Halloysite template, a ceramic substrate, is of a hollow cylindric structure, on which the fine Pd nanoparticles are uniformly formed by the reduction of palldate chloride to initiate electroless deposition. The electroless deposition of Ni is catalyzed by the Pd particles, which results in a uniform layer of Ni-P alloy on halloysite. The alloy is of a nanocrystalline structure, of which the average diameter is about 6 nm. After being heat-treated at 400 ℃, it contains both Ni and Ni12P5 crystal, meanwhile, the Ni crystal gets larger with an average size of 51.9 *** content of phosphorous in the Ni layer has a great influence on crystal structure. The metallized halloysite has a higher inherent coercive force, and a much lower saturation magnetization in its as-plated state, while after heattreatment, the inherent coercive force decreases drastically. These magnetic properties have great relationship with the superparamagnetism of Ni nanocrystalline and the stress anisotropy in Ni layer.

关键词： halloysite template electroless deposition Ni nanocrystalline inherent coercive force

Novel technology of electroless Ni-W-P on plastics and its interface behavior

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中国有色金属学会会刊：英文版 2004年第z1期14卷 136-139页

作者： WANG Tian-xu HU yong-jun MENG ji-long College of Mechanical Engineering South China University of TechnologyGuangzhou 510641 China College of Mechanical Engineering South China University of TechnologyGuangzhou 510641 China College of Mechanical Engineering South China University of TechnologyGuangzhou 510641 China

The electroless Ni-W-P coatings on polyoxymethylene(POM) were prepared. The POM was pretreated by hot spraying Al powder on it. Before the electroless Ni-W-P deposition, the POM with Al coating was flash plated in alkaline bath. The mechanism of Ni-W-P deposition was studied and the technology was optimized. The XRD analysis shows that the "as-deposited" Ni-W-P plating has mixed crystalline structure. The hardness value of deposits is more than HV700. The abrasion resistance of deposits is six times more than that of POM. Bending test was used to determine the cohesion between the deposits and the substrates. SEM was used to study the behavior of surface abrasion and interface bonding condition. The reason for the excellent cohesion was interpreted.

关键词： plastics electroless plating interface Ni alloy

Investigation of Domain Wall Velocity to External Fields for High-Quality Waveguide-Type Periodically Poled LiNbO_(3) Fabrication

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Journal of Rare Earths 2006年第z1期24卷 131-135页

作者： Soo woo Kwon woo Seok Yang H M Lee woo Kyung Kim Hang yong Lee Dae Ho Yoon Yo Seung Song Department of Materials Engineering Hankuk Aviation UniversityGoyang 412-791Korea Nano Bio-Photonics Team Korea Electronics Technology InstituteBundang 463-816Korea Department of Advanced Material Engineering Sungkyunkwan UniversitySuwon 440-746Korea

The Ti-doped waveguide-type periodically poled LiNbO_(3)(PPLN)were fabricated and the dependence of domain wall velocity on an external field applied for domain inversion was *** whole polarization reversal process was computer-controlled to regulate domain wall expansion at a feedback time shorter than 5μ*** coercive voltage and several values of excess voltage were applied on 500μm-thick wafers serially connected to a 1-MOhm external resistor which had an effect of the poling current reduction,*** deceleration of domain wall *** domain wall velocity is sensitive to the poling voltage,precisely speaking,to the excess *** domain wall velocities were 28.70,16.02 and 5.75μm·s^(-1)under poling field of 23.5,22.0 and 21.0 kV·mm^(-1),***,average duty cycle of PPLN is about 49.93%.

关键词： periodically poled lithium niobate coerciv field duty cycle domain wall velocity quasi phase matching