硅光电二极管陷阱辐射定标研究

介绍ＣｒｙｏＲａｄｌ低温绝对辐射计（ＨＡＣＲ），给出通过激光功率控制器（ＬＰＣ）调制过的Ｈｅ－Ｎｅ激光对所研制的Ｓｉ光电二极管陷阱探测系统进行定标的实验及结果分析     

复方丹参合剂对去卵巢大鼠骨矿盐代谢的影响

用测定骨矿盐含量的方法,分析了复方丹参合剂(三种不同剂量)对切除双侧卵巢后的大鼠骨矿盐代谢的影响。将健康4月龄雌性SD大鼠36只,随机分成6组:A组(正常对照组);B组(假去卵巢组);C组(去卵巢组);D组(去卵巢 合剂小剂量组);E组(去卵巢 合剂中等剂量组);F组(去卵巢 合剂大剂量组)。去卵巢手术后1 d开始,连续用药11周。结果表明,去卵巢大鼠骨干质量、干质量/体质量、骨灰质量、骨灰质量/体质量、骨灰质量占骨干质量比等均明显降低,复方丹参合剂可使去卵巢大鼠降低的骨干质量、骨干质量/体质量、骨灰质量、骨灰质量/体质量、骨灰质量占骨干质量比等均显著回升。提示复方丹参合剂具有良好的对抗由于去卵巢引起骨矿盐含量降低和骨丢失作用。     

碳酸钙对去卵巢大鼠骨元素代谢的影响

用测定骨元素含量的方法,分析了碳酸钙(CaCO3)对去卵巢大鼠骨元素代谢的影响。将健康4月龄雌性SD大鼠24只,用抽签法随机分成4组:正常对照组,假去卵巢组,去卵巢组,去卵巢 CaCO3组。去卵巢 CaCO3组大鼠于去卵巢手术后第2 d开始给予CaCO3灌胃,w(Ca)=20mg/kg,1次/d,持续11周。结果表明,去卵巢大鼠骨Ca、S、Mg、Mn等元素含量显著降低,Zn、Co含量降低,骨P含量增加;CaCO3可使去卵巢大鼠降低的骨Ca、S、Mg、Zn、Co、Mn等元素含量显著回升,骨P含量显著回降;CaCO3可纠正去卵巢大鼠的骨元素代谢紊乱。提示补钙防治骨质疏松是通过纠正骨矿物元素代谢紊乱而实现的。     

Unusual effect of molecular weight and concentration on thermoresponsive behaviors of well‐defined water‐soluble semirigid polymers

A series of water‐soluble semirigid thermoresponsive polymers with well‐defined molecular weights based on mesogen‐jacketed liquid crystal polymers (MJLCPs), poly[bis(N‐hydroxyisopropyl pyrrolidone) 2‐vinylterephthalate] (PHIPPVTA) have been synthesized via reversible addition fragmentation chain transfer (RAFT) polymerization. Dynamic light scattering (DLS) revealed that the novel monomer and polymers have thermoresponsive properties with cloud point in the range between 10 and 90 °C. The cloud point was increased by 56.2 °C when the polymer molecular weight increased from 0.47 × 10⁴ g mol^?1 to 3.69 × 10⁴ g mol^?1. In addition, the cloud point of PHIPPVTA was decreased by 18.8 °C with the increase of polymer concentration from 5 to 10 mg mL^?1. A slight increase (0.1–3.5 °C) of cloud point has been observed after knocking off the end‐groups of PHIPPVTA. Moreover, the cloud point of polymer increased with increasing of its molecular weight with or without the trithiocarbonate end‐groups, which showed the opposite trend comparing with other thermoresponsive polymers with flexible backbones. These polymers show a dramatic solvent isotopic effect that the cloud point in D₂O was lower than in H₂O. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Gold/photoredox-cocatalyzed atom transfer thiosulfonylation of alkynes: Stereoselective synthesis of vinylsulfones

We report a gold and photoredox combined radical approach for the rapid synthesis of thio-functionalized vinylsulfones from alkynes. Key features of this method include very mild conditions, broad substrate scope, excellent regio- and stereoselectivties, and 100% atom economy.     

单原子材料在二氧化碳催化中的技术经济分析与产业化应用前景

近年来, 随着科学研究的不断深入, 单原子催化剂由于具有高活性与高选择性等突出特点被广泛挖掘和应用. 作为连接多相与均相催化的桥梁, 单原子催化剂已经成为催化领域的重要研究对象之一, 具有广泛的工业化应用前景. 本文对单原子催化剂的发展历程、 特点及其在不同领域的应用进行了概括, 综合评述了当前CO₂还原领域的技术经济分析, 并首次对单原子材料催化转化CO₂进行了技术经济分析与计算. 最后, 对单原子催化剂在CO₂还原领域中工业化应用的未来发展方向及亟需解决的关键科学和技术问题进行了展望, 以期推动单原子催化材料的进一步广泛应用.     

室温离子液体作溶剂顶空气-质联用测定药物中溶剂残留

基于室温离子液体无蒸汽压、良好溶解性和分散性的特点,用室温离子液体[bm im][PF6]作溶剂顶空气-质联用测定非那雄胺中二氯甲烷、三氯甲烷及二氧六环的残留量,优化了顶空气-质联用分析条件。二氯甲烷、三氯甲烷及二氧六环的检出限分别为0.2、0.02和0.50 ng,线性相关系数大于0.99;相对标准偏差(RSD)0.39%~4.60%;回收率为90.5%~111.9%。室温离子液体作为顶空溶剂的灵敏度有所提高。     

肺超声伪影的产生机理、检测技术及临床应用

近年来,肺部超声技术越来越受到人们的关注.肺部超声可以对肺组织以及胸膜进行快速的视觉评估,用来诊断心源性肺水肿、急性呼吸窘迫综合征(ARDS)等肺部疾病.相较于CT、磁共振成像(MRI)而言,超声对人体无辐射危险,且超声技术简单、安全、成本相对较低.而肺超声伪影可以反映出诸多肺部组织病理信息,临床诊断中能观察到的肺部伪...