红细胞、血浆蛋白及溶酶体对汉防己甲素和汉防己乙素系统暴露的影响

目的：汉防己为防己科植物粉防己（Stephania tetrandra S. Moore）的干燥根。汉防己甲素和汉防己乙素是其两个主要成分,具有抗肿瘤等多方面药效活性。为了帮助进一步考察汉防己甲素和汉防己乙素的药效作用,我们对两个双苄基异喹啉类生物碱开展了大鼠和体外药代研究。方法：大鼠口服或静脉给药汉防己提取物、汉防己甲素或汉防己乙素单体化合物以阐明汉防己甲素和汉防己乙素的药代动力学特征;在体外检测汉防己甲素和汉防己乙素的血浆蛋白结合、全血-血浆分配、溶酶体捕获。以上实验产生的生物样品均采用液质联用技术进行分析。结果：研究发现汉防己甲素和汉防己乙素有两个药代特征,其一是这两个化合物的全血系统暴露水平均高于其各自血浆系统暴露水平,其二是在相同的给药剂量、动物实验条件及分析检测条件下,两个化合物在灌胃汉防己水提物后的系统暴露水平均高于其各自在灌胃单个化合物后的暴露水平。汉防己甲素和汉防己乙素的大鼠血浆游离药物分数约为2%～5%,其在大鼠红细胞浓度比在大鼠血浆浓度高5倍左右。溶酶体抑制剂阻碍溶酶体捕获这两个化合物并显著减少其在HEK-293细胞中浓度。 结论：血浆蛋白结合、红细胞结合及组织细胞中溶酶体捕获三个因素极大地限制了游离的汉防己甲素和汉防己乙素的系统暴露水平,该药代特点应在围绕这两个中药化合物开展药效研究时关注。     

模具工业的发展之路--数字化、快速化、市场化--2004中国·重庆模具产业发展论坛综述

介绍了2004中国·重庆模具产业发展论坛暨项目对接会概况,阐述了模具技术发展和市场开拓的方向和措施,最后指出模具的数字化是模具工业核心竞争力之所在,模具制造技术水平是制造业核心竞争力之所在.     

H, O,P,S和N对金属Ni塑性形变机制影响的第一性原理研究

本文基于密度泛函理论研究了H、O、P、S和N杂质以间隙式固溶于Ni(111)后对其变形能力的影响。发现：S、P在晶粒内部不稳定，不易存在于Ni(111)的间隙位置，而易向界面和表面扩散，H、O和N可在晶内分布，且N在Ni晶内分布的倾向性较大。对于Ni (111)<112>滑移系，P使得Ni层错能增大，而H、N、O、S降低了Ni的层错能，即H、N、O、S固溶于Ni使其沿(111)<112>滑移更为容易。总体来看，当外部环境介质H、N、O侵入到Ni基体时，由于使得体系的层错能降低，除产生的氧化、腐蚀等作用外，还使得该区域抵抗变形的能力下降，增大了蠕变变形的可能性。     

Effect of secondary carbides addition on the microstructure and mechanical properties of (Ti, W, Mo, V)(C, N)-based cermets

(Ti, W, Mo, V)(C, N)-based cermets were prepared by mixing Mo₂C, WC and TaC with ultrafine (Ti, W, Mo, V)(C, N) powders, and then processed via a conventional P/M technique. The effect of Mo₂C, WC and TaC on the microstructure and mechanical properties of (Ti, W, Mo, V)(C, N)-8 wt.% Ni-7 wt.% Co systems was investigated. The Mo₂C content was varied from 0 to 10 wt.% and additive WC or TaC was added at a level of 5 wt.% with Mo₂C addition. The results show that the densification of (Ti, W, Mo, V)(C, N)-8 wt.% Ni-7 wt.% Co cermets was improved significantly by the addition of Mo₂C. With the increase of Mo₂C content, there is a coarsening tendency in the microstructure of (Ti, 20W, 15Mo, 0.2V)(C, N)-8Ni-7Co system, but the refinement for (Ti, 15W, 5Mo, 0.2V)(C, N)-8Ni-7Co. TaC addition decreases the density of (Ti, 15W, 5Mo, 0.2V)(C, N)-10Mo₂C-8Ni-7Co cermet and thus weakens its bending strength. (Ti, 15W, 5Mo, 0.2V)(C, N)-10Mo₂C-5WC-8Ni-7Co cermet has optimal mechanical properties: bending strength of 1999 MPa, hardness (H_v) of 1677 MPa and toughness of 9.95 MPa m^1/2 respectively by adding WC, which is due to its ultrafine and weak core/rim structure.     

SiBNC陶瓷的制备与高温行为研究

本文通过六甲基二硅氮烷与二氯甲基硅烷和三氯化硼共聚缩合的方法,合成了SiBNC陶瓷先驱体。通过FT-IR与XPS对先驱体的化学组成与结构进行了表征,平面B-N单元与Si-N单元的随机排列形成了以–Si-N-B-为骨架的理想先驱体结构。先驱体在氮气气氛下加热到800°C后转化成多元的SiBNC陶瓷,1000°C裂解后的陶瓷产率为50.1wt%。在氮气气氛下,得到的SiBNC陶瓷在1700°C下保持无定形,在1800°C下形成Si3N4 结晶。但在氩气气氛中,得到的SiBNC陶瓷在1800°C形成明显的β-SiC 与BNC2结晶。     

重卡铸件、冲压焊接件锈蚀分析与改进

近年来,国内外因汽车锈蚀导致的退车、召回事件越来越多.如何提高重卡整车防腐质量,对企业的发展有着重要的意义.针对公司产品出现的锈蚀问题,利用扫描电子显微镜(SEM)对锈蚀点进行分析并结合锈蚀故障再现的验证方法,最终锁定了锈蚀的诱因,并采取了有效整改措施.     

La,Ce,Tb含量对(La,Ce,Tb) BO3发光性能的影响

采用高温固相法合成(La,Ce,Tb)BO3荧光粉,并对该荧光粉进行XRD和SEM分析。结果表明:(La,Ce,Tb)BO3的晶体结构和LaBO3相同,Ce3+,Tb3+的掺入没有改变晶体的结构,发光粉颗粒大小均匀,形貌规则,粒度在5μm左右。研究了(La,Ce,Tb)BO3的光谱性质,在(La,Ce,Tb)BO3的发射和激发光谱中除了有Tb3+的特征发射和激发峰外,还有Ce3+的特征发射和激发峰。     

TaC-SiC陶瓷的制备与表征

TaC-SiC陶瓷具有优异的耐超高温性能和良好的耐高温氧化性能,是一种可满足航空航天和高性能武器装备应用要求的理想陶瓷材料之一。本文以纳米钽粉和聚碳硅烷为原料,采用超声和球磨混合方式按照钽粉质量分数分别为5%、10%、25%、55%制备了不同陶瓷先驱体。通过SEM、TG、IR、XRD、EDS等表征先驱体的组成、结构以及裂解过程。结果表明：纳米钽粉均匀分散在聚碳硅烷中;先驱体的陶瓷产率随着Ta含量的增加而增加;1073 K时先驱体基本无机化,Ta开始转变为TaC,1673 K时,金属钽完全转化为TaC;先驱体转化得到的陶瓷具有分布均匀、组成稳定等优点。     

Density functional study of the mechanical and phonon properties of Al12X (X = Mo,Tc, Ru,W, Re,and Os) compounds

By means of first principles calculations, we have studied the structural, elastic, and phonon properties of the Al₁₂X (X = Mo, Tc, Ru, W, Re, and Os) compounds in cubic structure. The elastic constants of these compounds are calculated, then bulk modulus, shear modulus, Young's modulus, Possion's ratio, Debye temperature, hardness, and anisotropy value of polycrystalline aggregates are derived and relevant mechanical properties are compared with the available theoretical ones. Furthermore, the phonon dispersion curves, mode Grüneisen parameters, and thermo-dynamical properties such as free energy, entropy and heat capacity are computed and the obtained results are discussed in detail.     

克罗恩病患者英夫利西单抗相关基因多态性与血药浓度及疗效关联性研究

目的：探讨克罗恩病（CD）患者英夫利西单抗（IFX）相关基因多态性与血药浓度、免疫原性及疗效之间的关联性,以期为优化CD患者IFX治疗方案提供参考。方法：前瞻性收集2017年9月至2019年9月在本院使用IFX治疗的CD患者相关临床资料,给药前采用多重PCR技术结合高通量测序技术的靶向测序法测得患者TNF-α-308、TNF-α-238、TNF-α-857、TNFRSF1B、ABCB1、FCGR3A基因型,借助酶联免疫吸附法检测维持期IFX谷浓度。利用SPSS 20.0软件进行统计分析,并绘制ROC曲线求临床疗效及抗体（ATI）产生的浓度阈值。结果：研究共纳入111例患者,携带TNF-α-238突变基因的患者IFX谷浓度显著低于野生型（0.55±0.52） vs. （1.75±1.46）μg/mL（P=0.003）,而TNF-α-308、TNF-α-857、TNFRSF1B、ABCB1、FCGR3A不同基因型间IFX谷浓度差异无统计学意义。TNFRSF1B突变型（TG+GG）临床应答率显著高于野生型（TT）（75.0%vs. 42.3%）（P=0.001）,其他基因不同基因型患者间临床疗效差异无统计学意义（P>0.05）。IFX治疗克罗恩病的疗效及ATI的产生与谷浓度显著相关（P<0.01）。预测治疗后生物学反应及临床反应的IFX谷浓度最佳阈值分别为1.33、0.85 μg/mL;谷浓度≤0.51 μg/mL作为指标预测ATI产生的特异性为91.0%,敏感性66.7%。结论：TNF-α-238、TNFRSF1B基因多态性可分别影响IFX治疗CD患者的谷浓度与临床反应。未发现TNF-α-308、TNF-α-857、ABCB1、FCGR3A基因多态性明显影响IFX治疗CD的浓度或疗效。IFX谷浓度>1.33 μg/mL对生物学反应具一定的预测意义,而谷浓度≤0.51 μg/mL可作为ATI产生的预测指标。     

Microtribological and corrosion behaviors of 1H,1H,2H,2H-perfluorodecanethiol self-assembled films on copper surfaces

Fluoroorganic monolayers adsorped on copper are studied in terms of organization, structure, electrochemical behavior, corrosion and tribological properties. 1H,1H,2H,2H-perfluorodecanethiol thin films are grafted on copper via a self-assembling process. PM-IRRAS and XPS were used to investigate the organization, composition and structural properties of the SAMs. Cyclic voltammetry studies revealed a good oxidation blocking factor and polarization curves showed good anti-corrosion properties for the fluoroorganic film. However, these properties were inferior to those of n-dodecanethiol based SAMs. This was accounted for by the lower packing density and the larger number of defects of the 1H,1H,2H,2H-perfluorodecanethiol SAMs probably due to electrostatic and steric repulsion between fluorine atoms along the carbon chain and a number of CH₂ groups insufficient to permit good organization.Fluorine groups present in the monolayer of the fluoroorganic SAMs led to excellent lubricant properties for the ultrathin film. Surface wear resistance was also improved thanks to SAM grafting. 1H,1H,2H,2H-perfluorodecanethiol SAMs thus appear to be very interesting lubricants for copper as they improve surface mechanical properties by diminishing surface friction and wear.     

稀土La在纳米晶（W, Ni, Fe, La）复合粉末烧结过程中的作用机理

采用溶胶-喷雾干燥法制备纳米晶(W,Ni,Fe,La)复合粉末,研究了粉末在烧结过程中La对抑制鼓泡和晶粒长大的作用机理,通过XRD与SEM分析了La在烧结过程中的相转变规律和在合金中的存在形式,讨论了稀土La对合金液相烧结过程中扩散的影响。结果表明:稀土La在纳米复合粉末中主要以La2WO6与La4W2O15的形式存在。经液相烧结后,稀土La主要以二次相颗粒的形式分布于粘结相中,生成高温下能稳定存在的La4W2O15相,该相对杂质元素Ca、O具有很好的亲和力,起到晶界净化和晶内净化的作用。同时二次相颗粒存在于粘结相中,抑制了W在粘结相中的扩散,降低了W在粘结相中的溶解度,使得液相烧结溶解-析出过程减慢,从而抑制液相烧结阶段的晶粒长大和鼓泡现象。     

Electrolytic surface hardening of steel, cast iron and aluminium-bronze

T he electrolytic hardening is quite a m odern heat treatm entprocess,which can be applied to ferrous and non-ferrous alloys like alum inum bronzes. The norm al surfacehardeningprocessesare: (1)Flam ehardening (2)Induction hardening. (3)Laserhardening (4)Electrolytichardening H owever,out of the above four last two m ethods are m ore m odern.In this paperm odern process electrolytic hardening hasbeen discussed.Theeffortshavebeen m adeto setvarious process param eters, which give new approach…     

Synthesis,characterization,and biological activities of Pt(Ⅱ) and Pd(Ⅱ)complexes with 2'',3'',4'',5,7-pentahydroxy flavone

Pt(Ⅱ) and Pd(Ⅱ) complexes with 2',3',4',5,7-pentahydroxy-flavone were synthesized and characterized by elemental analysis, molar conductance, IR, 1HNMR, TG-DTA, UV-Vis spectroscopic techniques, and fluorescence analysis.The scavenging effect on the superoxide radical ( O-2 ) and the inhibitory effect on lipid peroxides were also investigated.Both the ligand and the complexes exhibit scavenging effect on superoxide radicals, and the effect of the complexes is greater than that of the ligand. The Pt(Ⅱ) complex exhibits the strongest scavenging efficiency. Both Pt(Ⅱ) and Pd(Ⅱ) complexes have the inhibitory effect on lipid peroxides, and the effect of the complexes is greater than that of the ligand, but the Pt(Ⅱ) complex has a high effect of promoting lipid peroxides.     

Effect of carbon source on the carbothermal reduction nitridation for synthesis of (Ti, W, Mo, V)(C, N) nanocrystalline powders

The effect of carbon source on the carbothermal reduction-nitridation during synthesizing (Ti, W, Mo, V)(C, N) nanocrystalline powders was investigated. For a systematic comparison, activated carbon, graphite and two kinds of carbon black powder were used as reducing agents in this study. Ultrafine (Ti, W, Mo, V)(C, N) powders with a particle size of ~ 200-500 nm have been produced at 1450 °C for 2 h by using nanosized carbon black source with small particle size. The presence of phases in the reaction products was characterized with X-ray diffraction (XRD) and the microstructure of carbon source powders and final products was studied by scanning electron microscopy (SEM). The results show that the formation of the Ti(C, N) phase is strongly dependent on the particle size of carbon source powders, and the synthesizing temperature of the Ti(C, N) phase decreases significantly from 1750 °C to 1300 °C by using nanosized carbon black, as compared with micron graphite. In addition, activated carbon with a particle size of 5-50 μm does not favor the dissolution of tungsten or molybdenum carbides into Ti(C, N) despite its large specific surface area.     

终轧温度对50W600无取向硅钢组织、织构和电磁性能的影响

利用工业试验和OM、SEM和EBSD等系统地研究了830 ℃和860 ℃终轧温度下50W600无取向硅钢组织结构的演变规律及成品电磁性能。结果表明,提高终轧温度有利于促进热轧板特别是其心部的再结晶和晶粒长大,促进退火冷轧板的晶粒长大。50W600无取向硅钢在热轧-冷轧-退火过程中的织构演变规律主要为高斯织构{110}<001>→{112}<110>、{001}<110>和{111}面纤维织构→{111}面纤维织构。终轧温度从830 ℃提高到860 ℃,一方面减弱了热轧板中的{111}面纤维织构组分,另一方面增强了冷轧板中的{111}面纤维织构组分并减弱了其{001}<110>织构组分,最终促进退火冷轧板中对磁性有害的{111}面纤维织构组分减弱和对磁性有利的{001}<110>织构组分增强。提高终轧温度有利于无取向硅钢的铁损降低和磁感应强度提高。     

Sn, Ga对Al-Ti异种合金真空钎焊的影响

在铝硅钎料中加入一定比例的锡和镓元素,具有改善接头组织形态、降低钎料熔点、提高钎料润湿铺展性、提高钎焊接头力学性能的作用,从而有效的改善了铝钛异种合金真空钎焊的工艺性能。     

W、B、Y微合金化高铌TiAl基合金高温抗氧化性研究

使用元素W、B、Y对Ti-45Al-8Nb合金进行了微合金化,研究了微合金化后高铌TiAl基合金在900℃静止空气中的断续氧化行为。结果表明,与Ti-45Al-8Nb合金相比,经过0.2B与0.1Y联合微合金化后合金的氧化增重小,氧化膜与基体的粘附性强,抗氧化性明显改善;经过0.2W与0.1Y微合金化后合金氧化增重明显,氧化膜容易脱落,合金抗氧化性下降;经过0.2B、0.2W、0.1Y联合微合金化后合金抗氧化性没有明显变化。对氧化膜进行的扫描电镜(SEM)、能谱分析(EDS)及X射线衍射(XRD)分析表明,联合添加B、Y促进了合金中的连续致密的Al2O3条带的形成,W、Y联合微合金化的合金中靠近基体处未形成连续的Al2O3条带,并且混合层中形成了较厚的低铌含量的TiO2层。W、B、Y联合微合金促进了混合层中富Al2O3层的形成。     

铷、铯钨青铜粉末及其透明隔热薄膜的研究

研究不同形貌的铷、铯钨青铜粉末及其薄膜的性能。通过水热反应制备棒状和片状的铷、铯钨青铜纳米粉末,并对粉末进行热处理,之后使用旋涂法在玻璃上制备钨青铜透明隔热薄膜。通过X射线衍射、扫描电镜、透射电镜等对粉末进行表征,并研究其光热性能。使用紫外可见近红外光谱分析钨青铜薄膜近红外屏蔽性能,并测试其隔热性能。结果表明,热处理后的钨青铜粉末具有优异的光热性能,具有光热治疗癌症的应用前景。相比于棒状,片状的铷、铯钨青铜薄膜具有更高的近红外屏蔽率,分别为95%和98.8%。使用片状铷、铯钨青铜薄膜的玻璃室内温度相比使用空白玻璃分别下降了9.4℃和8.5℃。综上,片状铷、铯钨青铜具有优异的近红外屏蔽性能,在节能和光热治疗领域具有巨大的应用前景。     

Bi掺杂Mg2Si的稳定性,弹性性能和电子结构的第一性原理计算

从动力学角度研究合金元素Bi对Mg_2Si的掺杂情况,采用CASTEP中基于密度泛函理论的第一性原理方法分析了合金元素Bi掺杂Mg_2Si的占位情况、结构稳定性、弹性性能和电子结构。计算结果表明:Mg_2Si、Mg-7Si_4Bi、Mg_8Si_3Bi均可稳定存在于体系中,Bi原子优先占据Mg_2Si晶体中Si原子位置,Mg_8Si_4Bi间隙固溶体不稳定存在体系中;Mg_Si、Mg_7Si_4Bi、Mg_8Si_3Bi均为脆性相,掺杂合金元素Bi后可以提高Mg_Si的韧性、合金化能力和导电性;Mg_2Si的成键本质是金属键、共价键和离子键的结合,Bi原子掺杂Mg2Si后产生Bi-Si和Bi-Mg键合作用,有利于提高体系的稳定性。