Results 11 to 20 of about 100,647 (133)

聚乙二醇-聚乙烯亚胺共聚物介导体外基因传递 [PDF]

open access: yesZhongshan Daxue xuebao. Yixue kexue ban, 2007
【目的】研究非病毒基因载体聚乙二醇(PEG)-聚乙烯亚胺(PEI)共聚物的组成对体外介导基因传递的影响。【方法】将含PEG不同分子量和接枝量的PEG-PEI共聚物,与DNA形成复合物。考察带正电荷的PEI与带负电荷的DNA的相互作用,测定了PEG-PEI/DNA复合物的粒径和Zeta电位,及对Hela细胞的毒性和转染率。【结果】PEG侧链并未明显影响PEI与DNA形成复合物的能力;连接PEG5000能够明显降低复合物的粒径;复合物的Zeta电位随着PEG接枝量的增加而降低 ...
张璇, 潘仕荣
doaj   +1 more source

小孔径壳聚糖/聚丙烯腈复合超滤膜的研制

open access: yesGongye shui chuli, 2018
以聚乙二醇二缩水甘油醚(PEGDGE)为交联剂,将壳聚糖(CTS)交联到聚丙烯腈(PAN)基膜的表面,制备了壳聚糖/聚丙烯腈复合超滤膜。探讨了交联剂浓度、交联温度及交联时间对CTS/PAN复合超滤膜性能的影响,确定了最佳制膜条件。结果表明,在最佳条件下所制备的CTS/PAN复合超滤膜对聚乙二醇4000的截留率达94%以上,膜面粗糙度降低,亲水性得到明显提高,增强了膜片的抗污染性能。
杨兴胜   +4 more
doaj   +2 more sources

A Multifunctional MXene/CNF/PVB Fabric via Layer‐by‐Layer Construction for Electromagnetic Interference Shielding, Joule Heating, and Infrared Stealth

open access: yesRare Metals, Volume 45, Issue 4, April 2026.
ABSTRACT The rapid advancement of 5G communication technology has intensified electromagnetic pollution, creating an urgent demand for flexible multifunctional fabrics with efficient electromagnetic interference (EMI) shielding performance. This study proposes a novel material‐stacked construction strategy to fabricate multifunctional MXene/cellulose ...
Zong‐Kai Yan   +9 more
wiley   +1 more source

Janus Nanofiber‐Architected Moisture‐Enabled Power Generator for Intelligent Sensing and Neuromorphic Application

open access: yesRare Metals, Volume 45, Issue 1, January 2026.
ABSTRACT Moist‐electric generators (MEGs) harness energy from ubiquitous ambient humidity, which has emerged as a promising way to collect energy irrespective of location and time. This study presents a high‐performance MEG employing a bilayer Janus nanofiber membrane: a hydrophilic layer (lithium chloride/citric acid/polyvinyl alcohol) for enhanced ...
Peng Chen   +7 more
wiley   +1 more source

Topical and transdermal botanical formulations of the Chinese pharmacopoeia—A review

open access: yesPhytotherapy Research, Volume 38, Issue 9, Page 4716-4735, September 2024.
Abstract In pharmaceutics, ingredients are classified as active ingredients and excipients. In topical/transdermal phytomedicines, an ingredient may serve both functions. Published information on these dual‐purpose ingredients and their pharmacological relevance is limited.
Jingyi Gu   +3 more
wiley   +1 more source

丙烯酸-丙烯酸酯-衣康酸共聚物的合成和阻垢分散性能

open access: yesGongye shui chuli, 2008
以丙烯酸、丙烯酸乙酯和衣康酸为单体,水为溶剂,过硫酸铵为引发剂,异丙醇为链转移剂,合成了丙烯酸-丙烯酸乙酯-衣康酸三元共聚物(AA-AE-IA),研究确定了共聚物合成的最佳条件:引发剂用量为5%,链转移剂用量为10%,聚合反应温度为90℃。采用静态蒸发浓缩法和极限碳酸盐硬度法,将三元共聚物与市售的同类阻垢分散剂进行阻垢性能的对比实验,结果表明:AA-AE-IA的阻垢效果优于同类市售阻垢剂,最佳用量为6mg/L,静态阻垢率高达90%。
刘振法   +4 more
doaj   +2 more sources

纳米SiO2-聚乙烯醇复合超滤膜的制备及应用

open access: yesGongye shui chuli, 2002
以水为溶剂,以聚乙二醇(PEG)为致孔剂,并通过向聚乙烯醇(PVA)溶液中添加纳米SiO2构成铸膜液。凝固浴为Na2SO4/KOH/H2O溶液。采用相转化过程制备纳米SiO2-PVA复合超滤膜。实验表明,膜孔径对压力是敏感的。考察了SiO2含量和PEG含量对膜性能的影响。该膜在对含油废水的超滤实验中表现出良好的抗污染性及稳定性。
姜云鹏, 王榕树
doaj   +2 more sources

响应面法优化两性超支化聚丙烯酰胺合成及性能研究

open access: yesGongye shui chuli, 2018
以丙烯酰胺、丙烯酰氧乙基三甲基氯化铵、2-丙烯酰胺-2-甲基丙磺酸、正硅酸乙酯为原料,季戊四醇为支化剂,硝酸铈铵作引发剂,制备了一种超支化两性聚丙烯酰胺(PADS)。在单因素实验基础上,利用响应面法优化了超支化聚丙烯酰胺的合成工艺条件,确定较佳工艺条件:引发剂占总单体质量的0.05%,正硅酸乙酯占丙烯酰胺质量的2.5%、反应温度50℃。在PADS投加量为25 mg/L、温度35℃、硅藻土悬浮液pH为6的条件下,硅藻土悬浮液上清液透光率和絮凝时间达97.69%和8 s ...
郭睿   +4 more
doaj   +2 more sources

异丁基乙烯基醚/马来酸酐共聚物改性聚乙烯醇的研究

open access: yes, 2008
采用异丁基乙烯基醚/马来酸酐共聚物对聚乙烯醇(PVA)进行共混改性,研究了改性PVA的耐水性及力学性能,发现改性后的PVA的耐水性及力学性能有明显提高,其中当异丁基乙烯基醚/马来酸酐共聚物的含量为2%时,共混薄膜的断裂伸长率达到300 ...
田军, 王剑峰, 严庆
core  

榆树皮胶粉制备改性天然高分子絮凝剂

open access: yesGongye shui chuli, 2013
在乙醇-水体系中以榆树皮胶粉、氯乙酸、丙烯酰胺为原料合成改性天然高分子絮凝剂,以产物黏度和模拟水浊度去除率为目标,研究了碱投加量、氯乙酸投加量、单体质量比、接枝共聚温度对产品性能的影响,得到了最佳合成工艺条件,并采用红外光谱对改性产物进行了分析。结果表明:当m(榆树皮胶粉)∶m(氢氧化钠)∶m(氯乙酸)∶m(丙烯酰胺)=5∶1∶1.2∶3,聚合温度为75℃时,产品具有最佳的絮凝效果和最高黏度,其他反应条件为碱化时间3 h、碱化温度70℃、聚合时间5 h。红外光谱表明,榆树皮胶粉发生了接枝共聚。
潘碌亭
doaj   +2 more sources

Home - About - Disclaimer - Privacy