液质联用研究人重组干细胞因子一级结构

通过高效液相色谱(HPLC)和质谱技术,对人重组干细胞因子(rhSCF)分子进行分析,以确证其一级结构.将rh-SCF样品胰酶酶切,HPLC-RPC分离,基质辅助激光解吸附电离-飞行时间串联质谱仪(MALDI-TOF-MS)对rhSCF的酶切肽段进行解析,并对rhSCF的O-糖基化和N-糖基化位点进行了分析.结果:(1)rhSCF分子质量得到测定;(2)rhSCF的一级结构得到确认,测定的肽质量谱的覆盖率达到94%,分子中有两对二硫键;(3)鉴定了样品中的N-糖基化位点,并对rhSCF产品的O-及N-连接糖型上的糖结构进行初步探讨.结果显示:rhSCF一级氨基酸序列和二硫键形成位置与理论上一致,糖基化特性符合毕赤酵母表达蛋白的糖基化特点

2,2′-Bipyridine and Malononitrile as Additives for Styrene Living Radical Polymerization

[中文文摘]研究了稳定自由基存在下苯乙烯的活性聚合。发现在 2 ,2′ 联吡啶的存在下 ,苯乙烯聚合的分子量控制效果提高 ,分子量可控 ,分子量分布较窄。在与丙二腈共同作用时 ,可在 4h内达到 85 %的转化率 ,分子量分布在 1 .5以下 ,分子量控制误差在 2 0 %以下。设计分子量在 1 0 ,0 0 0 90 ,0 0 0 ,实测分子量和理论分子量相近.[英文文摘]Living free radical polymerizations of styrene were studied using benzoyl peroxide as an initiator in the presence of TEMPO(2,2,6,6-tetramethylpiperidinyl-1-oxy). The effect of MN/bpy malononitrile/2,2′-bipyridine additives on the control of molecular weight is explored. It was found that styrene polymerization was distinctly accelerated by MN/bpy additives and the theoretic molecular weight tallie well with the experimental molecular weight. Using the additives in a 1∶1.2 molar mixture of BPO and TEMPO with molbpy∶mol TEMPO = 2∶1 , molMN ∶mol TEMPO = 2. 5 at 135 ℃, the conversion of the styrene polymerization reached 85 % , the polydispersitics is below 1.5 and the difference between the theoretic molecular weight and the experimental molecular weight was cont roled below 20 %.固体表面物理化学国家重点实验室基金资助项目 (1130

NLRP3炎性反应小体在缺血再灌注急性肾损伤大鼠肾组织中的表达研究

目的:研究NLRP3炎性反应小体在缺血再灌注急性肾损伤大鼠肾组织中的表达。方法:选取SD雄性大鼠14只,平均分为缺血再灌注组(A组)和假手术组(B组),对比两组之间血肌酐、尿素氮变化及NLRP3表达的差异情况。结果:A组大鼠血肌酐、尿素氮水平明显高于B组大鼠,差异有统计学意义(P<0.05);免疫组化显示缺血再灌注急性肾损伤组大鼠肾小管上皮细胞NLRP3的表达显著增强;病理学检查显示缺血再灌注组大鼠肾小管间质损伤较严重。结论:缺血再灌注急性肾损伤会伴随血肌酐水平升高以及肾组织NLRP3表达增强。厦门市科技局2016科技惠民项目[项目编号:3502Z20164060

一种酸酐固化环氧树脂/坡缕石纳米复合材料的制备方法

本发明涉及一种酸酐固化环氧树脂/坡缕石纳米复合材料的制备方法，包括：将坡缕石研磨成矿粉；对坡缕石矿粉进行煅烧活化处理；将环氧树脂加热液化，加入坡缕石混合、搅拌；坡缕石的加入量为环氧树脂质量的1-8％；加入酸酐固化剂，其加入量为环氧树脂质量的20-40％；将所得混合物搅拌然后抽真空脱气处理等即成复合材料。本产品一般用于浇铸或封装电子、电气产品并加热固化。本发明优点和积极效果在于：显著提高环氧树脂酸酐固化材料韧性，显著提高机械性能和热稳定性，实施方法简单，成本低廉

黄河三角洲农田土壤含水率空间变异特征研究

基于传统统计学和地统计学方法,定量分析了灌水前、后田块尺度下土壤含水率的空间变异性。结果表明,除灌水前10～20cm土层土壤含水率呈非正态分布外,其余各土层含水率均服从正态分布;随着土层深度的加深,灌水前、后各土层含水率均逐渐增加;除灌水前20～40cm土层及灌水后10～20、20～40cm土层土壤含水率呈中等变异性外,其余各土层均呈现弱变异特征;除灌水后20～40cm及40～60cm土层属于指数模型外,其余各土层含水率最优拟合模型为球状模型;灌水前、后各土层含水率均表现为强空间自相关性

Spatial Variability of Soil Water in Yellow River Delta

基于传统统计学和地统计学方法,定量分析了灌水前、后田块尺度下土壤含水率的空间变异性。结果表明,除灌水前10～20cm土层土壤含水率呈非正态分布外,其余各土层含水率均服从正态分布;随着土层深度的加深,灌水前、后各土层含水率均逐渐增加;除灌水前20～40cm土层及灌水后10～20、20～40cm土层土壤含水率呈中等变异性外,其余各土层均呈现弱变异特征;除灌水后20～40cm及40～60cm土层属于指数模型外,其余各土层含水率最优拟合模型为球状模型;灌水前、后各土层含水率均表现为强空间自相关性

THE RESEARCH OF 2,2′-BIPYRIDINE AND MALONONITRILE AS ADDITIVES FOR STYRENE LIVING RADICAL POLYMERIZATION

［中文文摘］研究了稳定自由基存在下苯乙烯的活性聚合 .发现在 2 ,2′ 联吡啶的存在下 ,苯乙烯聚合的分子量控制效果提高 ,分子量可控 ,分子量分布较窄 .在与丙二腈共同作用时 ,可在 4h内达到 85 %的转化率 ,分子量分布在 1 5以下 ,分子量控制误差在 2 0 %以下 .设计分子量在 1× 10 4 ～ 9× 10 4 的范围内 ,实测分子量和理论分子量相近 .［英文文摘］The living free radical polymerization of styrene was studied with benzoyl peroxide as the initiator in the presence of TEMPO (2,2,6,6 tetramethylpiperidinyl 1 oxy).It was found that styrene polymerization was distinctly accelerated by means of using malononitrile (MN) as additive.The purpose of this paper is to explore the effect of MN/bpy on the control of molecular weight.These mixture additives were able to control the polymerization of styrene to high conversion (85%) in 4 hours, and samples of molecular weight from 1 ×104 to 9 ×104 and with polydispersities of 1. 15 to 1. 4 were readily obtained. In comparison with the polymerization without any additives , these systems represented a dramatic improvement in the ability to control the molecular weight . The molecular weight of the polymer gradually increased with time , while the narrow molecular weight distribution remained unchanged. The molecular weight evolved in a nearly linear fashion with increasing conversion.Using a 1∶112 molar mixture of BPO and TEMPO with [ Bpy ]P[ TEMPO ] = 2P1 , [MN ]P[ TEMPO ] = 215 , the conversion of the polymerization at 135 ℃reached 85% in 4 hours , and the polydispersity was below 115 , and the difference between the theoretical molecular weight and the experimental molecular weight was controlled below 20%.固体表面物理化学国家重点实验室基金 (NO:1130

短期放牧对半干旱草地生态系统CO_2和N_2O排放的影响

通过在北方农牧带半干旱草地生态系统(山西右玉)设置不放牧、轻度放牧、中度放牧和重度放牧4个不同强度的放牧实验,运用静态-暗箱法测定放牧第一年生长季的温室气体通量,研究不同放牧强度对该地区温室气体通量的影响.结果表明:(1) CO_2和N_2O在生长季表现出随着温度和水分变化的明显季节动态变化,但是与不放牧相比,第一年不同放牧强度对CO_2和N_2O排放速率没有显著影响;(2)放牧显著降低了土壤含水量(