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181.
StudiesonHepatocyte┐TargetingMagneticResonanceImagingMacromolecularContrastMedia*FUYan-junandZHUORen-xi**(DepartmentofChemist...  相似文献   
182.
STUDY ON THE SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES OF SUCROSE POLYESTER   总被引:2,自引:0,他引:2  
1. INTRODUCTIONSucrose polyester (SPE) is neither metabolized nor absorbed, it makes no caloric contribution to the diet. Excessive dietary fat intake is associated with increasing risk of obesity, high blood cholesterol, hypertension, coronary heart disease and some types of cancer. At present, fat substitutes are fashionable all over the world. SPE is a new functional fat substitute, which is similar to ordinary oils in physical and chemical properties. In a word, the research and dev…  相似文献   
183.
CA15-3 is a circulating antigen that is relatively specific for human breast tissue. CA15-3 is significantly more sensitive than carcinoembryonic antigen in the evaluation of patients with both primary and metastatic breast cancer. CA15-3 levels are often measured by using radioimmunoassay and enzyme immunoassay (EIA) in clinic. These methods are carried out manually. Tedious processes, slow reaction, poor reproducibility are their major problems. Capillary electrophoretic immunoassay …  相似文献   
184.
Hydroxyethyl starches (HES) have been used medically as plasma volume expanders. They are composed of a starch backbone and substituted hydroxyethyl groups. The backbone is ?(1,4)-glycosidic-linked anhydroglucose units, which has branches formed by ?(1,6)-glycosidic bonds. Hydroxyethylation can take place at the C-2, C-3 and C-6 sites of the glucose rings, as well as at the hydroxyl groups of the substituted hydroxyethyl groups. Variation of the position and quantity of the substituted …  相似文献   
185.
本文应用SAXS与微机模型拟合(MCMI)研究了-LB(S为芪唑杰)薄膜与SA-LB(SA为芪唑盐/花生酸镉)薄膜的微观结构与超分子结构, 以及这类LB薄膜凝聚态不稳定的原因。结果指出: 第一, 从π-A曲线可知, S与A的脂肪链可以类似于脂肪酸晶胞形成二维类晶系结构; 第二, 随着分子比R~M=S/A=0到1, S和A之间发生了人分散相至连续相的相逆转; 第三, S在二维类晶系中处于不稳定的近似伸直型的高能态构象,然而, 哑铃形的芪唑基类似于芪趋向于作倾斜状密堆砌, S的两条脂肪链则倾向于转变为稳定的全反式燕尾开的低能态构象, 仅占S分子长约2/3的脂肪链亦降低了S分子间与S-A分子间的凝聚力, 这就导致了S连续相的二维类晶系存在大量晶格缺陷, 故只能形成4~6层不稳定的Y型LB薄膜; 第四, 存放一月后, 这种不稳定的S连续相的层状超分子结构极易存坏和崩塌。  相似文献   
186.
透氢钯复合膜的原理、制备及表征   总被引:2,自引:0,他引:2  
黄彦  李雪  范益群  徐南平 《化学进展》2006,18(2):230-238
钯及其合金膜由于具有透氢性好和耐高温的特点,除了用作氢气分离和纯化器外,还可以用作脱氢、制氢等反应的反应器,以实现反应和分离的一体化,并提高转化率和选择性。本文综述了钯基复合膜的原理、制备及表征,并重点介绍了本研究组的光催化镀膜工艺。  相似文献   
187.
Polyaniline, especially its acid-dopping composite material, is a kind of important photoelectric material due to its potential application in many fields1~3. However, it seems to be a problem that the polymers exhibit several deficiencies, including chemical and structural imperfections as a result of mislinkage, saturated sites, molecular weight distribution, the presence of the end groups and conformation defects. All of these defects affect the device efficiency and make it difficult to …  相似文献   
188.
Introduction Gastriccancerisoneofthemostcommonlyen counteredmalignantdiseasesworldwide,especiallyin AsiaandAfrica[1].Thecombinationofoperation,chemotherapyandradiotherapyisusedfortreatinggas triccarcinoma.However,the5yearsurvivalrateof patientsofgastricca…  相似文献   
189.
Approaches for preparation of porous oxides with different length scales are currently available[1?3]. Materials with hierarchical pore systems at two or three different length scales have also been prepared[4?7]. Such materials are important both for the…  相似文献   
190.
Capillary electrophoresis (CE) has become a useful and powerful separation technique and has many applications. Electrochemical detection (ED) has been shown to be one of the most sensitive detection techniques available for use in CE. Dual-electrode detection can expand the applicability of CE-ED1-5, the materials such as gold/mercury1,3, carbon fiber2, Pt4 and Au3,5 have been used for the two electrodes in dual-electrodes. As is well known, the electrochemical response of different c…  相似文献   
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