不同脱乙酰度壳聚糖接枝丙烯酰胺的合成与表征

从甲壳素出发，先制备了3种不同脱乙酰度的壳聚糖，选择过硫酸铵-亚硫酸氢钠为氧化还原体系引发剂，合成了壳聚糖接枝丙烯酰胺聚合物；通过红外光谱，电镜扫描对聚合物进行结构表征，结果表明壳聚糖结构发生了变化，通过在相同条件下比较壳聚糖不同脱乙酰度对接枝率的影响，得出了在脱乙酰度为68．5％时聚合物的接枝率最大为250％，其最佳合成工艺为：m（壳聚糖）：m（丙烯酰胺）=1：5，引发剂用量为体系质量分数的0．3％～0．4％，温度55～60℃，反应时间为2．5～3．0h。     

丙烯酸酯接枝共聚物在稠油降黏中的应用

摘 要:油溶性降黏剂降黏技术,作为一种新型的稠油开采和输送技术具有不同于其他稠油降黏技术的独特性及其适用范围,具有广阔的开发前景;其研究在石油领域非常活跃。根据油溶性降黏剂的降黏机理,针对丙烯酸丁酯、苯乙烯、丙烯酰胺三元共聚物,通过固定其他反应条件用TDI(甲苯二异腈酸酯)、氯化石蜡、平平加、硬脂酸对其进行了接枝改性处理,探讨了接枝改性物的品种和用量对降黏率的影响。所合成的丙烯酸酯接枝共聚物对稠油的降黏率最高可达94％左右。采用红外光谱仪器分析手段,对部分丙烯酸酯接枝共聚物的结构进行了表。结构表征数据分析表明,已合成的丙烯酸酯接枝共聚物符合所设计的结构特点。      

一类新型疏水缔合聚合物的合成及成胶性能

以甲氧基聚乙二醇丙烯酸酯(MPEGA)和甲基丙烯酸二甲氨基乙酯(DMAEMA)为均聚单体,通过乳液聚合制备一类新型疏水缔合型聚合物P(MPEGA-DMAEMA),采用FT-IR和1HNMR表征新型聚合物的化学结构;利用主剂P(MPEGA-DMAEMA)和交联剂醋酸铬形成凝胶体系,考察主剂P(MPEGA-DMAEMA)和交联剂醋酸铬的质量分数、pH值、温度、矿化度对新型聚合物凝胶体系成胶性能的影响.结果表明:当主剂P(MPEGA-DMAEMA)质量分数为1.2%、交联剂醋酸铬质量分数为0.2%、pH值为7、温度为45e时,该新型聚合物凝胶体系具有最佳的成胶强度.将新型聚合物凝胶体系应用于岩心封堵,在最佳成胶条件下,堵水率高于90%,堵油率低于40%,具有较好的选择封堵性.     

壳聚糖生产工艺的优选研究

用正交试验等方法优选壳聚糖生产中脱钙、脱蛋白质、脱乙酸基等工序的工艺条件。试验结果表明：用体积分数为3％的HCl脱钙15h可使制品的灰分含量＜1％；用质量分数为8％的NaOH煮沸90min脱蛋白质，可使制品总氮含量＜7％；在碱质量分数为42％、物料与碱液配比为1∶40、80℃保温18h的条件下，制品粘度＞2000mPa．s．脱乙酰度＞80％。     

制备条件对聚乙烯醇-壳聚糖凝胶性能的影响

以戊二醛为交联剂,由聚乙烯醇(PVA)和壳聚糖(CTS)混合交联得到一种水凝胶,考察了聚乙烯醇和壳聚糖的配比、交联剂用量和反应时间对聚乙烯醇/壳聚糖凝胶吸水率的影响。通过单因素实验,得出了聚乙烯醇/壳聚糖凝胶具有最佳溶胀性能时的条件:聚乙烯醇与壳聚糖的摩尔比为6∶1,交联剂戊二醛的体积分数为0.05%,反应时间9h。测定了该凝胶在不同pH值下的吸水率和吸附铜离子的性能,得出聚乙烯醇/壳聚糖凝胶在酸性介质的吸水率远远大于碱性介质,对铜离子(Cu2+)的吸附量比壳聚糖凝胶提高了33.7%,因此该凝胶吸附剂在工业废水处理重金属离子方面具有一定的优越性。     

淀粉接枝丙烯腈类吸水剂制造工艺及其原理

介绍了强吸水剂系列中淀粉接枝丙烯腈类吸水剂的制造工艺流程及其原理,并应用过硫酸铵作为引发剂,通过实验制出吸水倍率达1000倍的吸水剂.     

淀粉接枝丙烯腈类吸水剂的制造工艺及其原理

介绍了强吸水剂系列中淀粉接枝丙烯腈类吸水剂的制造工艺流程及其原理 ,并应用过硫酸铵作为引发剂 ,通过实验制出吸水倍率达 10 0 0倍的吸水剂     

羟基红花黄色素A-壳聚糖微球制备工艺研究

为探究羟基红花黄色素A-结合壳聚糖(HSYA-CS)微球的最佳制备工艺,采用乳化交联法制备,以微球的表观特征、粒径分布、包封率及载药量作为主要的评价指标,通过单因素考察和正交试验优化微球的最佳制备工艺。结果表明:戊二醛用量2.0 mL、交联温度50℃、投药比1∶5时,所制备的微球大小比较均一,黏连程度小,圆整度高,粒径范围2.0～4.6μm,载药量(6.53±0.42)%,包封率(68.04±0.46)%,正交设计证实上述条件下制备工艺最佳;乳化交联法制备HSYA-CS微球工艺方法稳定可行,产品性状较好,载药量和包封率较高,可为HSYA的临床应用效果的优化提供方法学借鉴。     

磺酸甜菜碱型聚丙烯酰胺/铬凝胶的自修复性能

为了探索磺酸甜菜碱型两性聚丙烯酰胺/铬凝胶的自修复行为,分析体系中聚丙烯酰胺的类型、酸的种类,以及重铬酸钠、硫脲的质量分数、硫酸钠质量浓度对凝胶自修复行为的影响.结果表明:磺酸甜菜碱型两性聚丙烯酰胺/铬凝胶的自修复行为主要与两性聚丙烯酰胺的分子结构有关,凝胶经剪切破碎后,聚合物分子的疏水作用和静电作用导致凝胶的重新聚集而实现自修复;无机盐硫酸钠质量浓度是影响凝胶自修复性能的一个重要因素,最佳硫酸钠质量浓度为220~1 600mg/L;酸的种类与凝胶的自修复性能无关,主要是影响凝胶的成胶时间,其中乳酸能够形成有机铬,铬离子经过水解和羟桥作用形成多核羟桥络离子,再与聚丙烯酰胺中的—COO—配位形成网络结构的凝胶;重铬酸钠和硫脲为体系提供Cr3+,它们的质量浓度与凝胶的自修复行为无关.南5-10-P50井组应用结果表明:60d后凝胶黏度恢复率超过60%,调剖后启动压力平均提高3 MPa以上.     

牡蛎壳制备活性钙

为充分利用牡蛎壳的钙资源 ,对乙醇在不同浓度、不同烧煮时间、不同配比条件对牡蛎壳粉中钙的活化效果及不同浓度的乳酸对活性钙的提取效果进行了研究。结果表明 :以活化温度 12 0℃ ,m(牡蛎壳粉 ) / g∶V(酒精 ) / m L为 1∶ 5,烧煮时间 3.5h活化效果最好 ;用体积分数为 85%乳酸提取钙的效果最佳。由牡蛎壳制备的乳酸钙含水分 1.9% ,游离酸 1.6% ,乳酸钙 95.1% ,磷 0 .3% ,钙 14.8%。     

Preparation of cationic chitosan-polyacrylamide flocculant and its properties in wastewater treatment

Chitosan derived from crab shells,was used to prepare the graft polymer in aqueous solution with acrylamide (AM) and methacrylatoethyl trimethyl ammonium chloride (DMC) as raw materials and ceric ammonium nitrate (CAN) as initiator.The floc-culation ability of the resulting polymer (PCAD) was studied in waste water treatment experiments.Its properties were determined on the basis of the transmittance of waste water after flocculation.The effects of chitosan and DMC content on PCAD’s flocculation ability wer...     

Ultrasonic-assisted condensation of chitosan with salicylaldehyde

In order to synthesize an improved adsorbent for heavy metal ions, we studied the condensation reaction of chitosan with salicylaldehyde in ethanol to form a Schiff base. The effect irradiating the reaction using an ultrasonic liquid processor was contrasted with conventional methods. The IR spectra of condensed chitosan prepared by the two methods showed that their molecular structures were identical. The reaction conditions, including solvents, ultrasonic power density and irradiation time, pH, and reactant ratio, were optimized by orthogonal design. A shorter reaction time and a higher product yield were obtained using ultrasonic-assisted synthesis compared with the traditional method. A condensation degree of 89.63% was achieved using the optimized conditions: i.e. ultrasonic irradiation at 180 W for 60 min; 95% ethanol as the solvent, pH 4.0, and salicylaldehyde:chitosan ratio of 6:1.     

Preparation and charaterization of self-assembled nanoparticles based on linolenic-acid modified chitosan

1 IntroductionHydrophobically modified water-soluble polymers,also known as hydrophobized polymers, are thosemodified by hydrophobic groups such as alkyl,arolkyl, and deoxycholic acid. In water, they canself-aggregate due to their intro- and/or intermolecularhydrophobic interaction. By this process, unique hy-drogel nanoparticles with hydrophobic core and hy-drophilic shell can be prepared, which is a new ap-proach to preparing the monodispersed hydrogelnanoparticles (Whitesides et al., 1991; …     

壳聚糖希夫碱铜配合物的制备及其催化性能

采用微波辐射加热法使壳聚糖与水杨醛反应生成壳聚糖希夫碱,然后将其与铜盐配位得到壳聚糖希夫碱铜配合物,用UV、FTIR、TG表征产物的结构,并探讨该配合物对过氧化氢分解的催化性能。研究结果表明:壳聚糖希夫碱铜配合物对过氧化氢有良好的催化活性,常温(25℃)常压,pH=7.0的条件下放置12 h,催化H2O2的分解达99.8%,该配合物重复使用3次还保持较好的催化活性。     

Analgesis and wound healing effect of chitosan and carboxymethyl chitosan on scalded rats

Analgesis and wound healing effect of chitosan and carboxymethyl chitosan on scalded rats were investigated. A II degree scald model was established in rats, which was subsequently treated with chitosan and carboxymethyl chitosan solution, respectively. The concentration of bradykinin and 5-hydroxytryptophan was detected by assaying enzyme-linked immunosorbent. Healing condition was observed and pathological sections were made to determine the healing effect of chitosan and carboxymethyl chitosan. Results showed that the concentration of bradykinin and 5-hydroxytryptophan peaked at the third hour post-wound in all groups, while the concentration of hydroxyproline peaked at the seventh day post-wound in both chitosan and carboxymethyl chitosan group. The concentration of bradykinin and 5-hydroxytryptophan of carboxymethyl chitosan group was significantly lower than that of control (P < 0.05), while that of chitosan group was similar to that of control (P > 0.05). These findings indicated that carboxymethyl chitosan reduced the concentration of algogenic substances, resulting in analgesia. During the whole recovery process, the hydroxyproline concentration in chitosan and carboxymethyl chitosan group on day 3 and 7 was significantly higher than that of control (P < 0.01); however the significance of such a highness decreased on day 14 (P < 0.05). These findings indicated that chitosan and carboxymethyl chitosan accelerated tissue repair. Meanwhile, chitosan performed better in healing than carboxymethyl chitosan in both decrustation and healing time. In conclusion, carboxymethyl chitosan showed significant analgesis and wound-healing promotion effect, but chitosan only showed wound-healing promotion effect.     

安徽省温度与心脑血管疾病死亡关系的广义叠加模型分析

本研究探讨了安徽省巢湖市、雨山区和天长市的温度与心脑血管疾病死亡之间的关系。从中国疾病预防控制中心收集2008-2011年这3个城市（区）居民的心脑血管疾病日死亡资料,采用Possion广义叠加模型研究了温度与心脑血管疾病死亡之间的暴露-反应曲线关系,并以最适宜温度为参照,分别估计高温和低温情况下气温每上升或下降1 °C,对应的心脑血管疾病死亡人数上升的百分比。结果显示,3个城市心脑血管疾病死亡与温度之间的暴露-反应曲线为J-型,即存在一个最适宜温度,心脑血管疾病的死亡风险在该最适宜温度达到最低,巢湖市、雨山区、天长市的最适宜温度分别为29.0°C、26.6°C、26.9°C。当温度低于最适宜温度时,温度每降低1 °C,巢湖市、雨山区和天长市的心脑血管疾病死亡人数分别增加1.06%（95%CI：0.39%~1.74%）、2.18%（95%CI：1.56%~2.81%）、0.89%（95%CI：-0.11%~1.90%）;当温度高于最适宜温度时,温度每升高1°C,3城市的心脑血管患者死亡人数分别增加2.92%（95%CI：-2.19%~8.30%）、4.87%（95%CI：-0.11%~10.10%）、2.06%（95%CI：-2.57%~6.91%）。研究结果表明,低温和高温均会对安徽省城市居民的心脑血管疾病死亡产生影响,且温度对心脑血管疾病死亡的影响还存在地域差异。因此,在研究温度对心脑血管疾病死亡的影响、制定相关的防御措施时,都需因地制宜地进行分析。     

IMPACT OF STARVATION ON SURVIVAL，MEAT CONDITION AND METABOLISM OF CHLAMYS FARRERI

The effects of 60-day starvation on survival rate. condition index (CI) , changes ofnutrient composition of different tissues, respiration and excretion of scallop ChlartnCs farreri were studiedin laboratory from Oct. 17 to Dec. 15 ,1997. Two groups (control and starvation with 200 individualseach) were cultured in two 2 m3 tanks, with 31 to 32 salinity water at 1 7 “C . Starvation effects were mea-sured alter 1 0, 20, 40 and 60 days. There was no mass mortality of scallops cf the two tanks and survivalrates of the control and starvation groups were 93 .5 % and 92.0 %, respectively. Starvation had strongeffect on the meat condition of the scallops, especially after 10 days; when relative lipid percentagedropped sharply while relative protein percentage increased. The impact of starvation on the oxygen consumption mtc (OCR) and the ammonia-N cxcretion mtc (AER) was obvious.     

典型深街谷内树木空间配置对行人呼吸高度处气流的影响

为揭示树木的不同空间配植方案对行人呼吸高度气流的影响,本文将树木视为均匀多孔介质,通过附加源项法从空气动力学角度用CFD模拟了H/W=2的典型深街谷几何内4种树木配植情景,实验表明,不同空间配置下树木对街谷内行人呼吸高度处局地气流的影响强弱在空间分布模式上差异悬殊：① 均匀种植的树木对街谷内行人呼吸高度的气流起到阻碍作用,不均匀种植则有效提升街谷的整体流速。4种空间配植方案下树木对气流的影响程度不同,阻碍作用从大到小的顺序为均匀间距8 m（Spa8m）>均匀间距6 m（Spa6m）>均匀间距20 m（Spa20m）>不均匀配植（Non-uniform）;对应的平均气流增强指标顺序为$\bar{D}_{spa8}$（-19.31%）<$\bar{D}_{spa6}$（-16.14%）<$\bar{D}_{spa20}$（-10.73%）<$\bar{D}_{non-uniform}$（1.25%）。② 对比不均匀和均匀的种植方案,不均匀植树的街谷内部行人呼吸高度的气流流速比其对照案例（均匀植树Spa8m方案）整体增强了106.49%。街谷中部不种树,在街谷两端配置树木并预留足够的自由空间的不均匀植树方案,能够让角涡渗入街谷中部,促使街谷内部的垂直漩涡和两端的水平角涡运动,增强湍流和垂直交换,有效减少了街道两端“风口效应”和街道中部“风影效应”的区域,改善了整个街谷行人呼吸平面的风环境。④ 合理空间配置的树木能够改善街谷内部的行人风环境。街谷内行人呼吸高度处的气流对局地条件很敏感,树木的局部配置（空间簇集、密度）将引起强烈的空间变化。在既有城市建筑布局条件下,如何通过谨慎的景观设计,利用树木等城市绿化措施有效地改善城市的行人风环境,缓解污染扩散、疾病传播等问题,本文的方法可提供一定的参考。