Results 11 to 20 of about 12,267 (168)
Zhejiang Daxue xuebao. Lixue ban, 2013 以三（3，5-二叔丁基水杨醛缩苯乙胺）镧La (OPEBS)3为引发剂引发L-丙交酯(L-LA)和ε-己内酯(ε-CL)的共聚，可控合成嵌段共聚物.研究了单体加料顺序、投料比、单体与引发剂的摩尔比(M/I)及聚合温度对L-LA和ε-CL共聚的影响.由石油醚抽提纯化的聚合物经GPC、1H NMR和DSC分析，表明该共聚物为L-LA和ε-CL嵌段共聚物.
BIEZhen-ying(别振英) +3 more
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Conservation Biology, EarlyView.Abstract Despite the crucial role of human impacts on biodiversity loss, many assessments of this loss focus on single metrics, such as species richness, and overlook the multidimensional effects of human activities. Because of its importance to ecosystem functioning, we investigated the functional diversity of medium‐ and large‐sized mammal ...
Xueyou Li +8 more
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Zhejiang Daxue xuebao. Lixue ban, 2006 系统研究了各种因素对复合膜的药物控释、稳定性、药物包埋率等性能的影响.最佳制备条件：pH=5.0、壳聚糖溶液质量分数为0.25%、海藻酸钠溶液质量分数为0.25%、海藻酸钠与壳聚糖的质量比为1：1.当壳聚糖溶液pH = 5.0时，复合膜的药物控释性能最强.通过Ca2+的交联，使替硝唑的包埋率达到96.1%.复合膜的溶胀度研究表明，在pH = 11的介质中具有最大的溶胀度.
LINXian-zhen(林咸真) +2 more
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Study on Preparation and Characterization of Low Methoxy Pectin/Chitosan Composite Membrane(低甲氧基果胶/壳聚糖复合膜的制备及特性研究) [PDF]
Shipin kexue jishu xuebao, 2019 Low-methoxy pectin/chitosan composite membranes were prepared through the tape casting method. The formation mechanism of the composite membranes and effects of pectin, chitosan, and glycerol on the structure and properties of the membranes were ...
LI Jie(李洁) +5 more
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Asparagus Oligosaccharide’s Purification and Protection of Acute Alcoholic Liver Injury in Kunming Mice [PDF]
, 2015 寡糖具有抗病毒、抗肿瘤、抗氧化、免疫调节等生物活性，是一种高活性物质，在医药和功能性食品领域显示了巨大的应用前景。与其它来源于植物、几丁质的寡糖相比，目前来源于海藻的寡糖尚未得到大规模开发。本研究前期工作中建立了利用微生物与龙须菜（Gracikarialemaneifarmis）共培养，一步法获得寡糖的方法，简化了生产步骤，降低了成本，并开展了龙须菜寡糖的各项活性研究与开发。本文研究了龙须菜寡糖的纯化方法，并研究其在动物生长、急性酒精肝损伤保护等方面的生理活性。 首先对龙须菜寡糖的纯化制备进行研究 ...
刘海凤
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Conservation Biology, EarlyView.Abstract Achieving global conservation policy goals requires the ability to set and measure progress toward science‐based targets for biodiversity. The species threat abatement and restoration (STAR) metric was developed to enable actors to set science‐based targets for species.
Louise Mair +17 more
wiley +1 more source
Theoretical calculation of cathode catalyst and electrolyte in lithium air battery [PDF]
, 2016 随着电动汽车的快速发展，寻找和开发具有高能量密度的新型锂二次电池显得至关重要，锂空气电池是目前研究最为活跃的体系之一。采用量子化学为主的理论方法，有助于深入认识和理解锂空气电池电化学界面的一些关键科学问题。本文从理论计算的角度出发，开展对于锂空气电池的正极催化剂材料及电解液等关键组件的研究。主要研究内容如下： 1.MnO晶体的(100)、(111)-Mn和(111)-O晶面对锂空气电池充放电过电势影响的机理研究。 在N掺杂石墨烯（NG）表面上均匀生长MnO晶体，该复合材料表现出了优异的OER催化性能 ...
雷鸣
core
Biodiversity‐driven spatial conservation planning to delineate temporally stable regions
Conservation Biology, EarlyView.Abstract The accelerating loss of biodiversity underscores the critical need for effective conservation strategies, particularly in the face of climate change and anthropogenic pressures. We devised a conservation planning framework that adopts a temporal stacking approach to species distribution models and landscape connectivity analyses. These models
Mattia Iannella +5 more
wiley +1 more source
Characterization of Condensed Tannins from Litchi Seed by Reflectron Modes and Linear Modes of MALDI-TOF MS [PDF]
, 2011 E-mail: zhouhc2010@yahoo.com.cn[中文文摘]利用不同模式的基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)分析荔枝果核缩合单宁.在反射模式(Reflectron modes)下,加速电压20.0 kV,反射电压23.0 kV,延时取出电压16.32 kV,聚焦电压9.45 kV,获得缩合单宁的准确结构单元组成和连接方式信息,其为三聚体至十八聚体组成的A型原花青定多聚物.在线性模式(Linear modes)下,加速电压20.0 kV,延时取出电压16.25 kV,
周海超 +4 more
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Zhejiang Daxue xuebao. Lixue ban, 2010 设计的生物质与聚合物共裂解工艺,共裂解产物中C3-C4烃成分占气态烃类的大部分,为可燃气的开发提供理论基础.从生物质与聚合物共裂解产物中气态烃类的分布可见：生物质与聚合物常压共裂解气体转化率更高；相对生物质与聚合物高压无氧共裂解, C1和C2烃类生成相对减少,常压共裂解有利于C3和C4烃烃类的生成,占总气态烃的64.6%(质量比).将毛细管柱与氢火焰离子化检测器(FID)联用,研究了生物质与聚合物共裂解产物中气态烃类的气相色谱分析.通过控制分析条件,有效地使各类烃获得有效的分离.柱温：程序升温 ...
CUIYan-li(崔艳丽) +4 more
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