质子交换膜燃料电池作为一种极具发展潜力的氢能源汽车动力电池,以氧还原催化剂为核心的膜电极对质子交换膜燃料电池的综合电化学性能有重要影响.电化学工作站作为评估氧还原催化剂催化性能的重要装置,准确、合理地评估氧还原催化剂的催化性能对推动氢能源汽车的大规模应用具有十分重要的意义.本文简要介绍了电化学工作站在质子交换膜燃料电池氧还原催化剂中的应用,重点介绍了采用循环伏安法和线性扫描伏安法评估氧还原催化剂催化性能的注意事项及主要参数指标,进一步地将膜电极组装成燃料电池的单电池,提出单电池的测试方案,旨在对采用电化学工作站评估质子交换膜燃料电池氧还原催化剂催化性能和单电池性能提供参考.

The influence of alloy composition and sintering temperature on the mechanical properties and reliability of WC–Co cemented carbides was studied theoretically and experimentally. For the first time, through a hybrid approach of thermodynamic calculations and Weibull distribution, the comprehensive performance of ultrafine WC–Co cemented carbides with different C contents and inhibitor type was investigated in detail. The carbon content of WC–10 wt-% Co–0.5 wt-% Cr cemented carbides was carefully controlled within the range of 5.38−5.52 wt-%. The contents of Cr and V are chosen to be in the range of 0–1 wt-%. It is found that WC–10 wt-% Co–0.5 wt-% Cr alloys with 5.46 wt-% C or 5.5 wt-% C show excellent mechanical properties and high reliability. WC–10 wt-% Co alloys with 0.5 wt-% Cr and 0.4 wt-% Cr–0.2 wt-% V demonstrate high mechanical property and reliability. The results of this study can be used to design process parameters during the manufacture of WC–Co cemented carbides.

Oxidative stress, inflammation and fibrosis can cause irreversible damage on cell structure and function of kidney and are key pathological factors in Diabetic Nephropathy (DN). Therefore, multi-target agents are urgently need for the clinical treatment of DN. Using Pirfenidone as a lead compound and based on the previous research, two novel series (5-trifluoromethyl)-2(1H)-pyridone analogs were designed and synthesized. SAR of (5-trifluoromethyl)-2(1H)-pyridone derivatives containing nitrogen heterocyclic ring have been established for in vitro potency. In addition, compound 8, a novel agent that act on multiple targets of anti-DN with IC50 of 90μM in NIH3T3 cell lines, t1/2 of 4.89±1.33h in male rats and LD50>2000mg/kg in mice, has been advanced to preclinical studies as an oral treatment for DN.

The hepatotoxicity of Chinese herbal medicine has attracted more and more attention in recent years .The traditional view that Chinese herbs are poisonless and harmless is worth considering .According to related research findings,liver injury due to the abuse of Chinese herbs caused by prescriptions from unqualified physicians is high retention .This paper summarizes the common Chinese medicine cau -sing liver injury, the pathologic types and clinical characteristics of liver injury induced by Chinese medicine , to explore the possible causes of liver injury induced by Chinese herbs.It is recommended to strengthen the management of traditional Chinese medicine prescriptions and prevent the abuse of Chinese materia medica .Liver injury induced by Chinese herbs should be taken seriously .

隐匿性HCV感染(OCI)是指在肝脏组织或者外周血单核细胞(PBMC)中能检测到HCV RNA,而在血清中多次检测均低于检测下限.那么,OCI临床意义如何?在临床上是否存在免疫抑制状态下HCV再激活?是否能成为抗HCV阳性且血清HCV RNA阴性患者出现肝功能异常的原因?甚至在一些自发或者治疗达到持续病毒学应答(SVR)的患者中,OCI是否是导致肝功能持续异常和肝病持续进展的首要原因?美国学者Elmasry等[1]在肝移植术后的患者出现HCV复发,应用直接抗病毒药物(DAA)获得SVR后进行OCI检测,以了解这些患者OCI的发生情况.

通过室温拉伸性能测试、金相组织观察、透射电镜分析以及取向分布函数测定,研究了25 mm厚时效态7475-T7351合金板材不同取向条件下的显微组织和力学性能,定量分析了织构与平面各向异性的关系.结果表明,7475-T7351合金板材纵向抗拉强度、屈服强度和伸长率分别为501MPa、428MPa、8.4％;横向抗拉强度、屈服强度和伸长率分别为491MPa、416MPa、8.9％.纵向抗拉强度和屈服强度比横向高约10 MPa,但伸长率变化很小,表明板材具有各向异性.7475-T7351合金板材中的晶体织构主要有Cu织构{112}＜111＞、S织构{123}＜634＞和Brass织构{110}＜112＞,这3种织构是由于铝合金冷轧后受层错能影响产生的.经计算,它们在合金中的体积分数分别为19.95％、16.67％、12.06％.此外,还有相对较弱的立方织构{001}＜100＞,为再结晶时形成的织构,体积分数为4.58％.通过对施密特因子的计算,表明不同取向条件下合金板材力学性能的各向异性与合金织构密切相关.

HBV related acute on chronic liver failure is one of the most common causes of death in patients with chronic hepatitis B. Currently, there exists many difficulties and doubts in the diagnosis and treatment to the disease. Here, in this review, we summarized some different related literatures and personal clinical experiences, aim to offer some beneficial references for clinicians and researchers.

The optical microscopy, orientation distribution function and scanning electron microscopy were used to investigate the fatigue properties and the rate of fatigue crack growth of 7475-T7351 alloy plate with thickness of 25 mm. The results show that the fatigue strength is anisotropic for the plate, it is 300 MPa along the transverse direction and 310 MPa along the longitudinal direction, respectively, and the fatigue life is longer than 1×107 cycle. Under the conditions of Kt=1, stress ratio R=0.1 and stress intensity factor amplitude ?K=30 MPa·m1/2, the fatigue crack growth rate da/dN along the longitudinal and transverse direction are 2.73×10?3?4.41×10?3 mm/cycle and 5.76×10?3?8.22×10?3 mm/cycle, respectively. The fatigue cracks mainly initiate on the non-metallic inclusions containing O, Na, Cl and coarse second phase on the sub-surface. A large number of striations are observed in the fatigue propagation zone, and a mixture of small dimples and cleavage is observed on the fracture surface in the fatigue fracture zone.

Nowadays Beidou satellite has fully realized real-time positioning of vehicles. However, we found that when BDS was used alone, the unsteadiness in the satellite signal transmission process may cause the problem of error positioning. In order to solve the problem, we propose to use the BDS/DR vehicle integrated navigation system. Then we choose the Extended Kalman algorithm to filter the data which includes the speed and displacement acquired by Beidou satellite navigation system. The results of the simulation show that Extended Kalman algorithm can effectively increases the reliability and fault-tolerance ability of BDS/DR navigation system, and avoids the diverging risk of error caused by Dead Reckoning system positioning and improve the positioning accuracy of the system.

Efficiency of parallel computation is always a fundamental research field in high performance computing. A study was carried out in this paper by combining the high performance parallel computing with numerical simulations of copper flash smelting furnace, to investigate influences of various factors upon the computing speed, such as the mesh types, the number of grid and CPU cores. It aims to provide some useful advices for the improvement of the computing efficiency for numerical simulations carried out on the parallel computing platform.

Pyridone compounds, such as pirfenidone (PFD) and fluorofenidone (AKF-PD), are multi-target anti-fibrotic agents. Using PFD and AKF-PD as the leading compounds, two series of novel (5-substituent)-2(1H)-pyridone compounds were synthesized with the purpose of maintaining multi-targeting property and overcoming the drawbacks of fast metabolism. These derivatives demonstrated good proliferation inhibiting activity against NIH3T3 cells by MTT assay with AKF-PD as the positive control. Compound 5b exhibited a high potent of anti-fibrosis with a IC50 of 0.08 mmol/L about 34 times of AKF-PD. The SAR of pyridone derivatives as anti-fibrosis agents was also discussed.

乙型肝炎病毒(HBV)感染是最严重危害人类健康公共卫生问题之一,全球约有3.5亿慢性HBV携带者,中国约占其中1/3左右,居世界第一位,其中15%～40%的慢性乙犁病毒性肝炎(慢性乙型肝炎)患者将发展为肝硬化和肝细胞癌[1].血液透析是治疗慢性肾衰竭的有效替代方法之一,维持性血液透析患者HBV感染率明显高于健康人群和慢性肾脏病非透析患者.血液透析患者感染HBV后不仅影响生活质量,而且也增加HBV相关肝脏疾病和移植肾失功等并发症.因此探讨维持性血液透析患者HBV感染的流行病学、易感因素、临床表现、诊断及防治具有重要的意义.

The optimum technique of micro-arc oxidiation for preparing biological activity ceramic film on titanium in an environment-friendly electrolyte was confirmed by orthogonal design.The result shows that the optimum condition of micro-arc oxidation process is as follows: 5g/L of magnecate,40g/L of silicate,5g/L of additive,165 mA/cm2 for oxidation current density,35 ℃ for solution temperature and it can obtain 6~10μm grey and smooth coating for 30 min oxidation.The coating contains abundant anatase and a little magnesium titanate,and exhibites ceramics performance.A large number of porous with uinform diameter distributes throughout the coating,which exhibites a certain extent coarseness.The oxidation film has better hydrophilicity than titanium matrix in the bionic solution.Apatite with biological activity can form on the oxidation film when the oxidation film is soaked in a saturated solution of calcium and phosphorus.

HBV慢性感染是诱发肝细胞癌(HCC)的首要因素之一,在HBV DNA的开放读码区S、C、P、X中,HBx基因及其所编码蛋白与HCC的关系最为密切[1],但它在转录活化中的具体机制和对病毒生命周期的影响的确切机制仍未明了,有待更深入的研究.而Raf-1作为原癌基因,对肿瘤的形成和发展起着重要作用,在促进肿瘤细胞增殖的同时,作为抗凋亡基因,阻止细胞凋亡的发生[2].本研究试图探讨HBx诱导Raf-1线粒体转位的现象及其机制.

The microstructures and tensile properties at different thermal exposure condition of 7475-T7351 alloy were studied by means of tensile test, OM and TEM analysis. The results show that when the thermal exposure temperature is higher than the second aging temperature of 7475-T7351 alloy, the strength drops dramatically and the elongation increases. When the alloy is thermal-exposed at 175 ℃ for 100 and 500 h, the strength decreases 29.7% and 40.4%, respectively. When the thermal exposure temperature is lower than the second aging temperature of the alloy and thermal exposure time is not so long, the tensile properties of the alloy have no change, but if the thermal exposure time is long, the tensile properties of the alloy will also decrease and the ductility also increase. For example, when 7475-T7351 alloy is thermal-exposed at 125 ℃ for 100 and 500 h, the strength decreases 0.9% and 3.2%, respectively, but when it is exposed at 150 ℃ for 100 and 500 h, the strength drops 11.4% and 19.0%, respectively. Coarsening of η′ (MgZn2) precipitates and widening of precipitate-free-zones (PFZ) should be responsible for the decay of 7475-T7351 alloy during thermal exposure condition.

Objective To seek ideal medicine for cerebralapoplexy with high potency and low toxicity.Methods A series of 3-substituted-1(3H)-isobenzofuranone 6a-g and 7a-g were synthesized from phthalic anhydride.The compound 6a-g was resolved.The antiplatelet activities of these compounds were evaluated using experiment of platelet aggregation in vitro.Results The levels of antiplatelet activity were displayed as follows: l-isomer dl-isomer d-isomer.Alkylphthalide was more active than the corresponding alkenephthalide.All these compounds were less active than n-butylphthalide(NBP,6c) and aspirin(Asp).Conclusion The antiplatelet effect of 1(3H)-isobenzofuranones may be associated with the magnitude and configuration of certain groups.

Objective To prepare sinomenine hydrochloride transfersomes and evaluate their qualities. MethodsThree different preparation methods including film dispersion, reverse phase evaporation, and ethanol injection methods were compared according to the encapsulation efficiency of transfersomes. Uniform design was applied to optimize the formulation and pharmaceutical process of reverse phase evaporation. The particle size, the appearance, the Z-potential, and the stability were also evaluated. ResultsThe transfersomes prepared by reverse-phase evaporation method possessed the highest encapsulation efficiency. The ideal combinations of preparation and formulation were: soya lecithin/sodium cholate was 200/30 mg/mg, chloroform/PBS was 5 mL/mL, pH of PBS was 6.5, added sinomenine hydrochloride was 10 mg. The transfersomes obtained were milky white translucent suspension, with a mean encapsulation efficiency of 62.2%. The shape of their particles was spherical or similar to spherical under microscope, which was smooth and disconglutinated with an average diameter of 96.4 nm, and a Z-potential of-35.93 mV. Aggregation or deposition was not observed after exposure under the temperature of 4 ℃ for 30 d. ConclusionThe preparation process of sinomenine hydrochloride transfersomes is feasible, the quality of obtained transfersomes is stable.It is expected to provide a new preparation for clinical use of sinomenine hydrochloride.

Effect of different forms and partical size of carbon on powder metallurgy friction material of copper-base was systemicly studied by mixing-forming-sintering and test-property ,SEM.The results show that there is biggish distinction on physical mechanical behaviour of different forms of carbon, due to the different processes of manufacture.however, the distinction of partical size and unit of the same form carbon powder affects the density and porosity of friction material of copper-base, and ulteriorly affect the frictional wearing behaviour of friction material. The experimentation testifies that it can get preferably general frictional wearing behaviour using crystalline flake graphite with certain partical size in friction material of powder metallurgy of copper-base.

Objective:To establish a method to determine related substance in pantoprazole Sodium.Methods:An RP-HPLC method was established.Lichrospher ODS C_8 column(4.6 mm×200 mm,5 μm)was used.The mobile phase was 35% volumers of acetonitrile,65% volumers of 1.12 g·L~(-1)Na_2HPO_4 and 0.18 g·L~(-1)NaH_2PO_4 with 0.1% n-octylamine in it,adjusted to pH 7.0 with H_3PO_4.The flow rate was 1.0 mL·min~(-1).The detection wave- length was set at 254 nm.The column temperature was 35℃.Results:The average recoveries were good.RSDs of reproduction were good.Conclusion:The method appeared to be simple rapid accurate and reproducible.