脱硫石膏复合胶凝材料及其激发效果研究

采用脱硫石膏为主要原料,制备了脱硫石膏-水泥-粉煤灰复合胶凝材料,考察了激发剂对其改性效果及显微结构特征。结果显示掺52%脱硫石膏,31%水泥,12%粉煤灰,5%激发剂时,复合胶凝材料后期强度较高,其28d强度可达到64.6MPa。14～28d试样抗压强度呈急剧增加趋势,其原因可能是后期水泥水化和粉煤灰二次水化所致。在脱硫石膏-水泥体系中,存在较多物理键和少量化学键,而掺加Al2O24-离子激发水泥和粉煤灰可形成致密凝聚-结晶复合结构。     

几种化学物质对粉煤灰水泥活性激发效果

借助于水泥砂浆试样的抗压强度跟踪测试,考察了几种无机化学物质对粉煤灰水泥的活性激发效果,同时借助于对水泥硬化体样品的XRD测试和SEM观察,深入通探讨了添加激发剂的粉煤灰水泥硬化体的水化产物和微观结构特征。试验结果表明:激发剂显著促进了粉煤灰水泥的活性激发,尤其是早期活性,水泥强度显著提高;XRD测试和SEM观察也表明,与空白样品相比,掺加激发剂的粉煤灰水泥硬化体明显表现出致密化的结构特征,粉煤灰颗粒表面趋向于粗糙化;Ca(OH)2衍射峰和石英衍射峰明显减弱,表明在激发剂作用下粉煤灰中的活性成分与水泥水化放出的Ca(OH)2之间化学反应得到了加剧。     

Cyanidin suppresses neoplastic cell transformation by directly targeting phosphatidylinositol 3-kinase

Cyanidin, an anthocyanidin found in fruits and vegetables, has been reported to possess anti-cancer effects. However, there is no study on the chemopreventive effect of cyanidin against neoplastic cell transformation and its molecular mechanisms. In the present study, we compare the anti-carcinogenic effects of cyanidin and cyanidin-3-glucoside (C3G) and investigate their underlying mechanisms. The inhibitory effect of cyanidin on EGF-induced cell transformation was higher than those of C3G in JB6 P+ mouse epidermal (JB6 P+) cells. Both cyanidin and C3G showed dose-dependent radical scavenging activities. It is indicated that the divergent inhibitory effects of cyanidin and C3G are not due to their antioxidant activities. We found that cyanidin, but not C3G, inhibited the EGF-induced Akt/p70S6K phosphorylation. Moreover, cyanidin directly suppressed the activity of PI3K by binding to PI3K directly in an ATP-competitive manner, which indicates that PI3K is one of the molecular targets of cyanidin.     

活化废轿车轮胎胶粉及其改性沥青的基本性能

采用双螺杆挤出机辅以活化剂制备活化废轿车轮胎胶粉(GTR),用其改性沥青或与苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)复合改性沥青。研究了活化GTR的溶胶、凝胶含量,考察了活化GTR改性沥青和活化GTR/SBS复合改性沥青的基本性能及微观形貌。结果表明,热剪切以及添加活化剂均能提高GTR的溶胶含量,使脱硫降解程度增大;用活化GTR改性沥青,改性沥青的针入度大幅增大,软化点、弹性回复、黏度明显降低;用活化GTR/SBS复合改性沥青,随着活化GTR含量的增大,改性沥青的软化点升高,针入度、延度、弹性回复降低,但经旋转薄膜老化后延度提高,耐老化性能提高;活化GTR在沥青中的粒径明显减小,分散性得到改善,而活化GTR/SBS复合改性沥青时,GTR均匀分散于SBS的网络结构中。     

国内大规模MDEA脱碳技术在中海油成功应用——以中海油东方天然气处理厂为例

中国海洋石油总公司（以下简称中海油）近年来为开发在南中国海发现的一批高含CO₂的天然气田,通过与国内相关单位联合攻关并消化吸收国外MDEA溶液脱除CO₂技术,依靠自身及国内力量,在海南省东方市建成了国内大规模的MDEA脱除CO₂装置。具有MDEA贫液、半贫液二段吸收,减压、汽提二次解吸再生特点的CO₂脱除工艺流程不仅降低了装置投资,而且具有高CO₂净化度、低能耗和溶剂损失少等优势,该装置年平均稳定完好运行达350天,净化气质CO₂含量小于1.5%,完全满足下游用户对气质的要求。经多年实际运行证明,该技术应用于大规模CO₂脱除装置是合理和可行的,近年来在中海油已得到广泛应用。     

新型过氧化氢漂白活化剂4-(2-壬酰氧基乙氧基羰基氧基)苯磺酸钠的合成

研究了以2-壬酰氧基乙基氯甲酸酯和对羟基苯磺酸钠为原料,水为溶剂,氢氧化钠为缚酸剂,合成一种新型过氧化氢漂白活化剂4-(2-壬酰氧基乙氧基羰基氧基)苯磺酸钠的清洁工艺,考察了影响合成反应的主要因素。适宜的工艺条件为:n(2-壬酰氧基乙基氯甲酸酯)∶n(对羟基苯磺酸钠)∶n(氢氧化钠)=2.0∶1∶2.5,水为溶剂,反应温度60℃,反应时间4h,4-(2-壬酰氧基乙氧基羰基氧基)苯磺酸钠的收率高于67.0%。结果表明:该工艺具有操作简单、易控,环境友好等优点。     

Ultrastructural and immunohistochemical study of the effect of sodium alendronate in the progression of experimental periodontitis in rats

The aim of the present research was to investigate the ultrastructural aspects and the immunoexpression of receptor activator of NFκB ligand (RANKL) and osteoprotegerin (OPG) on experimental periodontal disease of alendronate (ALN)‐treated rats. Male Wistar rats received daily injections of 2.5 mg/kg body weight of ALN during 7 days previously and 7, 14, and 21 days after the insertion of a 4.0 silk suture into the gingival sulcus around the right upper second molar. Specimens were fixed in 0.1% glutaraldehyde + 4% formaldehyde under microwave irradiation, decalcified in 4.13% EDTA and paraffin embedded for TRAP histochemistry and immunohistochemistry for RANKL and OPG, or embedded in Spurr epoxy resin for TEM analysis. ALN reduced the activity of osteoclasts and significantly decreased the resorption of the alveolar crest. In the control group the alveolar crest appeared resorbed by TRAP‐positive osteoclasts, which presented ultrastructural features of activated cells. The immunoexpression of RANKL was not inhibited by the drug; however, the expression of OPG was increased in the treated animals. The alveolar crest of ALN‐treated specimens at 21 days showed signs of osteonecrosis, like empty osteocyte lacunae, the exposed bone regions and bacterial infection. The results showed that ALN treatment in individuals with periodontal disease represents a risk of osteonecrosis because of the reduced activity of osteoclasts resultant of the increased immunoexpression of OPG. Microsc. Res. Tech. 77:902–909, 2014. © 2014 Wiley Periodicals, Inc.     

In vitro stability and compatibility of tenecteplase in central venous access devices

Central venous access devices (CVADs) aid in the delivery of nutritional support, infusion therapy, and hemodialysis. Maintaining continuous flow through these devices is challenging, because they are susceptible to complications such as thrombi occlusion. Therefore, CVADs may require treatment with anticoagulant or thrombolytic agents. Using these agents as locking solutions has been widely investigated; however, few publications have described the compatibility of the therapeutic with the CVAD itself. The objective of this investigation was to evaluate the in vitro stability and compatibility of a thrombolytic biologic agent, tenecteplase, with various CVAD materials. Tenecteplase was reconstituted to 1 mg/mL with either sterile water for injection or bacteriostatic water for injection (0.9% benzyl alcohol) then incubated in glass vials, polysulfone/silicone vascular access ports, and polyurethane or silicone catheters for up to 96 hours. Biochemical assays including protein monomer, protein one-chain, and in vitro bioactivity were used to assess tenecteplase's compatibility with the investigated diluents and materials every 24 hours. Antimicrobial testing was also performed for up to 28 days on bacteriostatic water for injection-reconstituted samples only. Our results showed tenecteplase to be compatible with both types of diluents (in glass vials) and catheters for up to 72 hours. Furthermore, tenecteplase was compatible with the polysulfone/silicone vascular access ports for up to 24 hours. Finally, bacteriostatic water for injection-reconstituted tenecteplase effectively met USP criteria for the inhibition of growth of micro-organisms. This study serves as an example of a best practice to evaluate the in vitro stability and compatibility of a biologic agent with CVAD materials.     

某低品位难选白钨矿常温浮选试验研究

江西某白钨矿石含钨0.23%,原矿钨品位低、嵌布粒度较细、萤石含量高,是典型的白钨-方解石-萤石（或重晶石）型难选白钨矿.针对该难选白钨矿中有价金属钨无法有效回收的现状,对其进行了试验研究,结果表明,采用组合药剂（GYW＋731）做捕收剂,新型药剂WH做活化剂,实现了该低品位难选白钨矿的常温浮选,闭路试验获得了品位为35.11%,回收率为72.20%的钨精矿.