HBV感染者外周血T淋巴细胞表面共刺激分子和T淋巴细胞亚群的检测及临床意义

目的: 探讨HBV感染者外周血T淋巴细胞表面共刺激分子和T淋巴细胞亚群与HBV-DNA的关系及在HBV感染发展中尤其是重症化进程（如慢加急性肝功能衰竭）的作用。方法: 选取浙江大学医学院附属第一医院及浙江省青春医院收治的120例慢性HBV感染者,其中慢性乙型病毒性肝炎（CHB）患者60例,乙肝肝硬化（LC）患者30例,慢加急性肝功能衰竭(ACLF)患者30例。CHB组又分为HBeAg阳性组30例,HBeAg阴性组30例。以同期30例健康体检者为对照组。采用流式细胞术检测各组外周血CD+4和CD+8T细胞表面程序性死亡因子（PD-1）,细胞毒T淋巴细胞相关抗原-4(CTLA-4),T细胞免疫球蛋白黏蛋白分子-3(Tim3),T淋巴细胞（CD+3）,辅助T细胞（CD+4）和抑制T细胞（CD+8)百分比,PCR法检测各组HBV-DNA载量。采用Pearson分析相关性。结果: HBV感染者CD+4CTLA-4和CD+8CTLA-4的表达均低于对照组,其中CHB组CD+4CTLA-4、CD+8CTLA-4、CD+8PD1、CD+4Tim3和CD+8Tim3的表达均高于LC组和ACLF组,差异均具有统计学意义（P<0.05）。HBV感染者CD+3、CD+4、CD+4/CD+8的表达均低于对照组,CD+8的表达高于对照组,CHB组CD+3,CD+4和CD+4/CD+8均高于LC组和ACLF组,CD+8的表达均低于LC组和ACLF组,CHB组HBV-DNA水平高于LC组和ACLF组,差异均具有统计学意义（P<0.05）。CHB组中HBeAg阳性组CD+4CTLA-4、CD+8CTLA-4、CD+3、CD+4和CD+4/CD+8的表达均低于HBeAg阴性组,CD+4PD1、CD+8PD1、CD+4Tim3、CD+8Tim3和CD+8的表达均高于HBeAg阴性组（P<0.05）。HBV感染者HBV-DNA与CD+8PD-1,CD+8Tim3存在显著正相关性（P<0.05）,与CD+4CTLA-4,CD+8CTLA-4,CD+4Tim3,CD+4PD-1,CD+3,CD+4和CD+8不具有相关性（P＞0.05）。与LC组比较,ACLF组患者CD+4 PD-1的表达水平升高,CD+8 CTLA-4的表达水平降低。结论: 外周血T淋巴细胞表面共刺激分子和T淋巴细胞亚群比例与HBV感染发展尤其是重症化进展（如ACLF）相关联,对疾病的疗效和预后判断具有一定的临床应用价值。     

燃烧合成ZrC-ZrB_2陶瓷颗粒增强ZrCo_3B_2基复合材料

以Co、Zr和B4C粉末为原材料,通过燃烧合成技术制备了Zr C-ZrB2/Zr Co3B2复合材料。采用DSC、XRD和SEM探索了Co含量对Co-Zr-B4C体系反应行为和产物的影响,并分析了该体系相转变路径。结果表明,随Co含量的增加,燃烧温度和产物的颗粒尺寸逐渐降低。Co-Zr-B4C体系的相转变路径为:Co+Zr+B4C→Co+Zr+B4C+Co Zr→Co+Zr+B4C+Co Zr+Co Zr2+Co B+Co13B7+Zr C+ZrB2→Zr+Co Zr+Co Zr2+Co B+Zr C+ZrB2+Zr Co3B2→Zr C+ZrB2+Zr Co3B2。     

热处理工艺对低屈强比高强度结构钢组织与性能的影响

采用两相区淬火+回火(L+T)、淬火+两相区淬火+回火(Q+L+T)和正火+回火(N+T)工艺,对实验室试制的低屈强比高强度结构钢进行系列热处理试验,并研究了3种热处理工艺对试验钢组织和性能的影响。结果表明,两相区淬火前,试验钢的初始组织及正火、淬火时冷却速率的差异决定了最终的组织性能,采用L+T工艺,试验钢的强度和屈强比最高;采用Q+L+T工艺,试验钢的屈强比略有下降,但强度却大幅下降;采用N+T工艺,试验钢的屈强比最低,强度与采用Q+L+T工艺相近。     

油茶皂甙对缺血大鼠心肌线粒体Na+、Ca2+、Mg2+含量及ATPase 活性的影响1

目的 观察大鼠心肌缺血时心肌线粒体Na⁺、Ca²⁺、Mg²⁺含量、ATPase 活性的变化及油茶皂甙(SQS)对它们的影响。方法 以皮下多点注射异丙肾上腺素(ISO 4 mg · kg^-1)诱导心肌缺血损伤为模型, 测定Na +、Ca²⁺、Mg²⁺含量及ATPase 活性。结果 心肌缺血时线粒体Mg²⁺含量明显减少, Na⁺、Ca²⁺含量显著增多;Na⁺-K⁺-ATPase 、Ca²⁺-Mg²⁺-ATPase 活性显著下降。SQS(0.2 mg ·kg^-1, iv)能显著对抗缺血心肌线粒体Na⁺、Ca²⁺、Mg²⁺含量及Na⁺-K⁺-ATPase 、Ca²⁺-Mg²⁺-ATPase 活性的上述改变。结论 SQS 具有抗钠钙超载的心肌细胞保护作用。     

Y12Cr18Ni9Cu易切削钢的平衡凝固相变与MnS析出行为

采用Thermo-Calc热力学软件对Y12Cr18Ni9Cu易切削钢在500～1800℃的析出相进行了热力学计算并得到了平衡凝固相变路径图。结果表明,Y12Cr18Ni9Cu易切削钢的平衡相主要有MnS、液相、δ-铁素体、奥氏体、M₂₃C₆、M₂(C,N)、σ相。平衡凝固和冷却相变路径：液相→液相+MnS→液相+δ-铁素体+MnS→液相+δ-铁素体+MnS+奥氏体→δ-铁素体+MnS+奥氏体→MnS+奥氏体→MnS+M₂₃C₆+奥氏体→MnS+M₂₃C₆+奥氏体+M₂(C, N)→MnS+M₂₃C₆+σ相+奥氏体+M₂(C, N)。随着S含量增加,MnS的析出量逐渐增加,析出温度也逐渐升高,Mn含量变化对MnS相的析出量几乎没有影响,但Mn含量增加会使MnS析出温度升高。Y12Cr18Ni9Cu易切削钢中的硫化物呈球形、椭球形、纺锤形或短棒状并以...     

改性橘子皮对铜、铅和锌的吸附特性及吸附机制(英文)

将橘子皮经氢氧化钠和氯化钙处理,得到改性橘子皮生物吸附剂(SCOP)。用红外光谱(IR)、扫描电镜(SEM)和N2-吸附法对其形貌和特性进行表征;通过静态吸附实验,研究pH、起始金属离子浓度等因素对改性橘子皮SCOP吸附Cu2+、Pb2+和Zn2+的影响。等温吸附结果表明,SCOP对Cu2+、Pb2+和Zn2+的吸附符合Langmuir方程,根据Langmuir方程计算的SCOP对Cu2+、Pb2+和Zn2+的饱和吸附量分别为70.73,209.8和56.18mg/g。根据静态吸附实验结果,用动态柱吸附实现了水溶液中Pb2+和Zn2+的分离。吸附过程中离子交换发生了重要作用,重金属离子与吸附剂中的Ca2+离子发生离子交换。     

XHC法-HR型铬(重金属)废水治理机技术特点

正沈阳庭宇环保科技有限公司(原沈阳红日环保高新技术研究所)吴振庭高级工程师的研究发明专利——除铬灵-吸附剂(CGL-X)重金属综合治理药剂,能与废水中的重金属Cr6+、Cr3+、Zn2+、Ni2+、Cu2+、Fe2+、Fe3+、Al3+等,在中、碱性条件下,直接发生吸附-还原-沉淀反应达到新标准GB21900-2008表3的高要求(其中Cr6+达到未检出,可根治Cr6+的污染源)。对含有六价铬的混合重金属废水进行综合治理的同时达标排放,该技术亦可适用于分流后各单一重金属元素的治理;该药剂无毒、无味、无污染;依据除铬灵-吸附剂(CGL-X)药剂原理设计制造的连续(间歇)式HR型铬(重金属)废水治     

改性甘蔗渣填充柱对铅离子的吸附

制备改性甘蔗渣并探讨了其对Pb2+的动态吸附,在单一体系中研究填充粒径、溶液初始浓度和流速等对Pb2+动态吸附的影响,考察填充柱的重复使用情况;在两组分体系中考察Cu2+和Zn2+对Pb2+动态吸附的影响。结果表明:单一体系中,粒径、流速及初始浓度对Pb2+的动态吸附影响较小(吸附容量:118.9~148.6 mg/g),填充柱可在较宽的实验条件下使用,改性甘蔗渣可反复使用。两组分体系中,改性甘蔗渣对Pb2+的吸附亲和力显著高于对Cu2+和Zn2+的,吸附中存在明显的竞争取代过程;改性甘蔗渣填充柱可实现Pb2+、Cu2+和Pb2+、Zn2+的选择性分离。金属离子的吸附过程伴随着H+的释放过程,酸度越高,填充柱对重金属离子的吸附容量越小。     

热处理对建筑用20MnV钢组织与性能的影响

采用光学显微镜(OM)、扫描电镜(SEM)、万能拉伸试验机等研究了完全正火、亚温正火/亚温淬火对冷轧+回火态20MnV钢组织与性能的影响。结果表明:冷轧+回火态20MnV钢的组织由针状铁素体+块状铁素体+珠光体组成,完全正火+冷轧+回火态20MnV钢中的珠光体中片状渗碳体演变成断续分布的球状或者短棒状;800℃正火+冷轧+回火态20MnV钢的组织为铁素体+M/A岛+细小碳化物;800℃淬火+冷轧+回火态20MnV钢的组织为铁素体+回火索氏体,晶内和晶界上弥散分布着细小碳化物颗粒。冷轧+回火态20MnV钢具有较高的强塑性和较低的低温冲击韧性,完全正火/亚温正火+冷轧+回火态20MnV钢的强度和塑性相对冷轧+回火态试样有不同程度降低,但是低温冲击吸收能量明显提高,在正火温度为800℃时强度降低最为显著;亚温淬火+冷轧+回火态20MnV钢的强度与冷轧+回火态试样相当,断后伸长率略有减小,而-25℃和-45℃冲击吸收能量明显提升。与冷轧+回火态20MnV钢冲击断口截面上的剪切裂纹相比,800℃正火/800℃淬火+冷轧+回火态20MnV钢中的微裂纹数量更少、长度和宽度更小,裂纹扩展呈现弯曲和曲折状;800℃淬火+冷轧+回火态20MnV钢具有较高的强塑性和最佳的低温冲击韧性。     

金属阳离子在锂辉石浮选中的活化行为及作用机理

在油酸浮选锂辉石体系中分别加入Ca^2+、Al^3+、Fe^3+离子,通过单矿物浮选试验、金属离子吸附量检测、金属离子水解组份浓度计算、矿物表面动电位测试、红外光谱检测以及量子化学模拟计算研究Ca^2+、Al^3+、Fe^3+离子对锂辉石浮选的活化行为和作用机理。结果表明:Ca^2+离子的最佳活化区间为pH大于12的强碱性条件,Al^3+离子的最佳活化pH为6.47,而Fe^3+离子的最佳活化pH为7.25;在这些pH区间内,锂辉石浮选回收率和金属离子吸附量均达到最大值。在锂辉石浮选过程中起活化作用的有效组份为它们分别对应的氢氧化物沉淀。Ca^2+、Al^3+、Fe^3+离子可使锂辉石表面动电位向正值方向显著偏移;Ca^2+离子在锂辉石表面双电层的外层发生静电吸附,Al^3+和Fe^3+离子在锂辉石表面双电层的内层发生特性吸附。钙原子与锂辉石矿物表面吸附后形成的Ca—O键的键强较小,以离子键为主;铁原子与矿物表面形成Fe—O化学键的键强较大,含有一定的共价键组份;而铝原子与矿物表面吸附后形成的Al—O键的键长、键强等参数介于钙、铁的参数之间。油酸在Ca^2+活化后的锂辉石表面发生了化学吸附和少量的物理吸附,而在Al^3+、Fe^3+活化后的锂辉石表面发生了较为强烈的化学吸附。     

溶胶-凝胶法制备TiO2纳米颗粒及其光催化性能

考察了通过溶胶-凝胶法进行过渡金属(Fe3 、Zn2 、Co2 、Ni2 、Cr3 和Sn4 )和稀土元素(La3 、Pr3 、Nd3 、Ce4 、Sm3 、Tb3 、Eu.3 、Gd3 、Y3 和Dy3 )掺杂的TiO2纳米颗粒的光催化活性,以及通过超声波处理反应过程中的溶胶所制备得到的TiO2纳米颗粒的光催化活性.结果表明:0.5%Sn4 、0.5%La3 、0.5%Y3 和0.5%Eu3 (质量分数)掺杂的TiO2纳米颗粒在降解甲基橙溶液的反应中,其光催化活性提高2%～7%;其它的掺杂则使TiO2纳米颗粒的光催化活性降低0.5%～25%;在TiO2纳米颗粒的制备过程中,对溶胶进行超声辐照可使其光催化活性提高15%以上,这是提高TiO2纳米颗粒光催化活性的一条新途径.     

Comparison of 2A12 aluminium alloy joint by ultrasonic assisted friction stir welding and friction stir welding

Ultrasonic assisted friction stir welding （UAFSW） is a recent modification of conventional friction stir welding, which adds ultrasonic energy directly into the friction stir welding area by the pin. In this study, 2A12 aluminum alloy was welded by this process and conventional, respectively. The tensile tests, microstructure and fracture surface of FSW joint and UAFSW joint were analyzed. The research results show that the surface forming texture of ultrasonic assisted friction stir welding joint, compared with conventional, is finer and more uniform, showing metallic matte color. The grains are much finer in weld nugget zone, thermo-mechanically affected zone and heat-affected zone; S-phase particles size is much smaller and distribution is more homogeneous in the matrix. The tensile strength of UAFSW joint is 94. 13% of base metal, and the elongation is 11.77%. The tensile strength of FSW joint is 83.15% of base metal, and the elongation is 8.81%. The tests results reveal that ultrasonic vibration can improve the tensile strength and the elongation of welded joints.     

Effect of variable polarity frequency on 2A14-T6 aluminum alloy welds using HPVP-GTAW process

Hybrid ultrahigh frequency pulse variable polarity gas tungsten arc welding （HPVP-GTAW） for 2A14-T6 high strength aluminum alloy was carried out and the effects of variable polarity frequency with constant pulse current frequency 40 kHz on weld bead geometry, microstrueture and microhardness were analyzed. Experimental results indicate that, compared to that of the conventional VP-GTAW process, the weld depth and ratio of weld depth to width are improved significantly by the variable polarity frequency in the HPVP-GTAW process, which the ratio of weld depth to width is improved by 36% at equal variable polarity frequency of 100 Hz, and improved by 55% with that of 200 Hz. Weld microstructure and microhardness distribution are changed obviously with the increase of variable polarity frequency. In the conventional VP-GTA W process, the grains in weld central zone are coarser, and the microhardness in weld central zone and fusion zone is about 95 HV and the lowest 82 HV, respectively. The microhardness is enhanced to a certain extent both in the weld central zone and fusion zone with the variation of variable polarity frequency in the HPVP-GTAW process due to the refinement and uniformity of weld microstructure. With the variable polarity frequency of 600 Hz, the microhardness in weld central zone and fusion zone reaches nearly 110 HV and 97 HV, respectively.     

Development of an electrode intelligent design system based on adaptive fuzzy neural network and genetic algorithm

The coating on the electrodes contains many kinds of raw materials which affect significantly on the mechanical properties of deposited metals. It is still a problem how to predict and control the mechanical properties of deposited metals directly according to the components of coating on the electrodes. In this paper an electrode intelligent design system is developed by means of fuzzy neural network technology and genetic algorithm,, dynamic link library, object linking and embedding and multithreading. The front-end application and customer interface of the system is realized by using visual C ＋＋ program language and taking SQL Server 2000 as background database. It realizes series functions including automatic design of electrode formula, intelligent prediction of electrode properties, inquiry of electrode information, output of process report based on normalized template and electronic storage and search of relative files.     

Detection of keyhole entrance and exit in plasma arc welding

Sensing of keyhole shape and size is important for controlling of plasma arc welding process. In this study, a synchronous vision system is developed by using two CCD cameras to observe the keyhole entrance and exit simultaneously. Experiments are conducted on stainless steel workpiece, Whole keyhole exit image and part of keyhole entrance image are captured synchronously under different welding conditions. Image processing and calibration algorithms are proposed. The boundary and front point of the keyhole entrance and exit are extracted respectively. The effects of welding current and welding speed on ,front point of keyhole entrance and exit are analyzed. Compared to the front point of the keyhole entrance, the position of the front point of the keyhole exit is better to reflect the variation of the welding parameters.     

Neural network prediction of the shunt current in resistance spot welding

An error back propagation （BP） neural network prediction model was established for the shunt current compensation in series resistance spot welding. The input variables for the neural network consist of the resistivity of the material, the thickness of workpiece and the spot spacing, and the shunt rate is outputted. A simplified calculation for the shunt rate was presented based on the feature of the constant-current resistance spot welding and the variation of the resistance in resistance spot welding process, and then the data generated by simplified calculation were used to train and adjust the neural network model. The neural network model proposed was used to predict the shunt rate in the spot welding of 20# mlid steel （in Chinese classification） （in 2. 0 mm thickness） and 10# mild steel （in 1.5 mm and 1.0 mm thickness）. The maximum relative prediction errors are, respectively, 2. 83%, 1.77% and 3.67%. Shunt current compensation experiments were peoCormed based on the neural network prediction model proposed to check the diameter difference of nuggets. Experimental results show that maximum nugget diameter deviation is less than 4% for both 10# and 20# mlid steels with spot spacing of 30 mm and 50 mm.     

Effect of groove angle and preheating temperature on temperature profile and fluid velocity in weld pool

The three dimensiotud transient weld pool dynamics are numerically analyzed ,for Forcearc welding, which is a new gas metal arc welding technology to get deep fusion penetration with smaller angle sf V groove to enhance welding efficiency significantly. The influence of groove angle and preheatin,g temperature on heat and .fluid .flow is studied and compared to get an optimal welding parameter. Good agreement is shown between the predicted and experimental results, such as weld bead cross-section and thermal cycles. It can he seen that an apprpriate groove angle could be used to replace high preheating temperature to get inproced penetration and thermal cycles.     

Welding deformation control of medium-thickness structures made by advanced high strength steel

In order to investigate the residual angular deformation in fillet welding of T-joint of HG785 high strength steel with a medium thickness plate, both detailed thermo-mechanical finite element simulation and conventional gas metal arc welding experiment were carried out in the present study. In-process deformation control method using backheating method to reduce the residual deformation was discussed.     

Optimization of HPVP-GTAW process parameters for Al-Mg aluminum alloy welded joints

Optimization of hybrid ultrahigh frequency pulse variable polarity gas tungsten arc welding （HPVP-GTAW） process was carried out to obtain the optimum weld characteristics of 5AO6-HX4 aluminum-magnesium alloy sheets of 3 mm thickness. The square butt joints were produced by HPVP-GTA W process, the microstructure and mechanical properties were systematically investigated. It is observed that the process parameters influence the weld microstructure and mechanical properties significantly. Weld microstructure is mainly composed of grid a （A1） solid solution, with a large number of intermetallic （ Mg2Al3 ） precipitates distributed in the matrix. The amount of ~ （ Mg2Al3 ） precipitates has an obvious difference with different parameters. Compared with that of the base material, tensile strength of 5AO6-HX4 alloy welded joints has a certain reduction, as well as the elongation and reduction of area. The optimized welding process parameters for 5A06-HX4 alloy sheets are presented.     

Enhanced thermal stability by pre-charged hydrogen of a Zr-based bulk metallic glass

Tb³⁺/Dy³⁺ and Eu³⁺/Sm³⁺ doped rare-earth borate glasses have been synthesized and characterized. Under UV excitation, Dy³⁺, Tb³⁺, Sm³⁺ and Eu³⁺ emit intense yellowish white, green, reddish orange and red lights, respectively. In Tb³⁺/Dy³⁺ co-doped glasses, the enhancement of Tb³⁺ green emission is observed, and the sensitization is related to the efficient energy transfer from Dy³⁺ to Tb³⁺. In Eu³⁺/Sm³⁺ co-doped glasses, the excitation wavelength range of Eu³⁺ emission is broadened owing to the energy transfer from Sm³⁺ to Eu³⁺. This broadening makes the Ar⁺ 488 nm wavelength laser a powerful excitation source for Eu³⁺ fluorescence. The rare-earth doped glasses with various visible emissions are useful for developing new color light sources, fluorescent display devices, UV-sensor and tunable visible lasers.