CA／CAT共混不对称纳滤膜分离特性的研究

制备了ＣＡ／ＣＡＴ共混物不对称纳滤膜,膜对单价与多价阴离子能实现有效分离,并能去除小分子有机物。在１ＭＰａ操作压力下,料液温度为１５－２５℃,膜对１０００ｍｇ／Ｌ的ＮａＣｌ水溶液的截留率为１５％－６０％,而１０００ｍｇ／Ｌ的Ｎａ２ＳＯ４水溶液截留率为８５％－９８％,     

纳滤膜及其表面活性剂分离特性的研究

制备了不同规格的ＣＡ－ＣＴＡ混合纤维素纳滤膜，在１．０ＭＰａ下，对１０００ｍｇ／ＬＮａＣｌ截留率达５０％～８０％，透水率２０～６０Ｌ／ｍ２·ｈ．对１００ｍｇ／ＬＭｇＳＯ４截留率达９０％～９８％，透水率２０～６０Ｌ／ｍ２·ｈ．对１０００ｍｇ／Ｌ葡萄糖截留率达９０％～９５％，透水率２０～６０Ｌ／ｍ２·ｈ．并用该膜对十二烷基苯磺酸钠的分离特性进行了初探．ＣＡ－ＣＴＡ混合纤维素钠滤膜适用于阴离子表面活性剂的分离，其截留率达９６％～９８％，透水率２０～４０Ｌ／ｍ２·ｈ．     

ABS塑料镀金工艺的改进

１　ＡＢＳ塑料的表面金属化以化学法在塑料件表面上形成与基体有一定结合能力的金属层。步骤如下：（１）化学涂油　ＮａＯＨ　４０～５０ｇ／Ｌ;Ｎａ２ＣＯ３　１５～２０ｇ／Ｌ;Ｎａ３ＰＯ４　１５～２０ｇ／Ｌ;表面活性剂　３～５ｍｌ／Ｌ;温度　５０～６０℃;时间　１５～２０ｍｉｎ。（２）化学粗化　ＣｒＯ３　３５０～４００ｇ／Ｌ;Ｈ２ＳＯ４　３８０～４００ｇ／Ｌ;温度　５０～６０℃;时间　２０～３０ｍｉｎ。（３）敏化、活化溶液　采用的胶体钯活化液,ＰａＣｌ２　０．８～１．０ｇ／Ｌ;ＳｎＣｌ２·２Ｈ２Ｏ　５０…     

用电偶法评价不锈钢钝化膜在强酸介质中的自钝能力

采用电偶极化法,评价了１Ｃｒ１８Ｎｉ９Ｔｉ不锈钢阳极钝化膜和ＳＵＳ－３６不锈钢原始钝化膜在含有Ｈ２Ｏ４（２４０ｇ／Ｌ）＋Ｎａ２ＳＯ４（７０ｇ／Ｌ）＋ＨＣＨＯ（２５ｇ／Ｌ）Ｆｅ＾３＋（３５．４ｍｇ／Ｌ）＋Ｃｌ＾－（２００ｍｇ／Ｌ）的７０℃维尼纶醛化液中的自钝能力,发现它们的钝态－活态面积比在临界值里都有活,钝态的转变。实验结果表明,钝态光盘设备在缩醛化的生产工艺操作中,因机械损伤造成钝化膜的局部破损     

中空纤维超滤膜处理油田含油污水的研究

采用不同材料的中空纤维超滤膜对油田污水进行了实验研究，研究了料液循环速度、操作压力、操作温度和料液浓缩倍数对膜透过性能的影响，探讨了不同清洗方法对膜透过性能的恢复效果。在原液含油量为１００ｍｇ／Ｌ以上，进口压力为０．１６ＭＰａ，出口压力为０．０８ＭＰａ时，膜的透水通量可达１５ｍｌ·ｃｍ＾－２·ｈ＾－１以上，透过液含油量小于１０ｍｇ／Ｌ。不同的膜材料应用不同的清洗方法可达到较好的效果。     

润滑油酮苯脱蜡溶剂回收用聚酰亚胺纳滤膜分离性能的研究

主要研究了聚酰亚胺纳滤膜分离酮苯一润滑油的性能．考察了操作压力、温度、料液流量、料液中润滑油浓度及酮苯比等因素对膜通量和截留率的影响，并考察了长期运行情况下膜的分离性能．结果表明，随压力增大、温度升高和料液流量增大，膜通量也随之增大；料液中润滑油浓度的增加使膜通量减小，料液中酮苯比的增加可增大膜的通量；以上各种情况对膜的截留率影响不大，截留率稳定在95％以上；在40天的运行期内膜的分离性能变化不大，说明此聚酰亚胺膜具有较强的抗污染能力．     

共聚物电解质MA－Na_2／AA－Na水溶液的粘度特性

对共聚物电解质ＭＡ－Ｎａ２（顺丁烯二酸钠）／ＡＡ－Ｎａ（丙烯酸钠）水溶液ηＳＰ／Ｃ（比浓粘度）与浓度的关系、中性盐及溶液ｐＨ对ηＳＰ／Ｃ的影响进行了研究。结果表明，稀释ＭＡ－Ｎａ２／ＡＡ－Ｎａ溶液时，ηＳＰ／Ｃ急剧上升，而稀释含中性盐（ＫＣｌ或ＣａＣｌ２）的ＭＡ－Ｎａ２／ＡＡ－Ｎａ溶液体系时（中性盐含量保持０．０１ｍｏｌ／Ｌ），ηＳＰ／Ｃ的变化却不大。添加极少量（＜０．０５％）中性盐，可使ＭＡ－Ｎａ２／ＡＡ－Ｎａ溶液体系的ηＳＰ／Ｃ大幅度下降，当中性盐浓度大于０．０５％时，ηＳＰ／Ｃ趋于稳定。溶液ｐＨ＝８时，ηＳＰ／Ｃ最高，ｐＨ＜８或ｐＨ＞８时，ηＳＰ／Ｃ迅速降低。     

高通量聚丙烯腈超滤膜的研究

以聚丙烯腈（ＰＡＮ）为原料,二甲基乙酰胺（ＤＭＡＣ）为溶剂,研究了铸膜液组成和若干因素对膜性能的影响。选择适当的膜液组成和制膜条件,可制得截留相对分子质量为１５万（Ｒ＝９０％）,透水量达１５０％～２００ｍＬ（ｃｍ＾２·ｈ）的超滤膜。     

共聚物电解质MA—Na2／AA—Na水溶液的粘度特性

对共聚物电解质ＭＡ－Ｎａ２（顺丁烯二酸钠）／ＡＡ－Ｎａ（丙烯酸钠）水溶液ηｓｐ／Ｃ（比浓粘度）与浓度的关系、中性盐及溶液ｐＨ对ηｓｐ／Ｃ的影响进行了研究。结果表明，稀释ＭＡ－Ｎａ２／ＡＡ－Ｎａ溶液时，ηｓｐ／Ｃ急剧上升，而稀释含中性盐（ＫＣｌ或ＣａＣｌ２）的ＭＡ－Ｎａ２／ＡＡ－Ｎａ溶液体系时（中性盐含量保持０．０１ｍｏｌ／Ｌ），ηｓｐ／Ｃ的变化却不大。添加极少量（〈０．０５％）中性盐，可使ＭＡ－Ｎ     

单柱离子色谱法测定化学镀镍液中的HPO32-和H2PO-2

应用ＨＩＣ－６Ａ型离子色谱仪,以１．５ｍｍｏｌ／Ｌ苯甲酸钠作淋洗液,可快速分离和测定化学镀镍液中的ＨＰＯ３＾２－和Ｈ２ＰＯ２＾－的线性范围分别为１０￣２５０ｍｇ／Ｌ和１５￣１２０ｍｇ／Ｌ,精密度分别为０．５％和１．３％,最低检出浓度分别为０．７ｍｇ／Ｌ和０．８ｍｇ／Ｌ。     

Functional performance of silicified microcrystalline cellulose versus microcrystalline cellulose: a case study

Background: During the development of a tablet dosage form of an investigational compound, R411, several aspects were identified as critical quality attributes that required optimization. The use of nonsolvent processing prevented the moisture-induced physical changes in the drug product but presented manufacturing challenges related to sticking during compression and slowdown in dissolution after storage at stress conditions. Aim: The aim of this study was to evaluate silicified microcrystalline cellulose (SMCC), microcrystalline cellulose (MCC), and physical mixture of MCC–colloidal silicon dioxide (MCC/CSD at 98:2 ratio) as extragranular compression aids to address the processing and dissolution stability issues of this formulation. Methods: The compactibility and stickiness upon compression over extended period of time as well as the dissolution of R411 formulations incorporating the aforementioned compression aids were investigated. In addition, the water sorption/desorption properties of these compression aids were determined. Results: All formulations showed comparable compactibility irrespective of the compression aid used. Nevertheless, MCC alone or in a physical mixture with CSD showed sticking of the lower punches, whereas SMCC resulted in clean punch surface during extended compression runs. Furthermore, the three compression aids were compared for their effect on dissolution stability after storage at stress conditions. The formulations containing SMCC provided superior dissolution stability over the other compression aids evaluated in the study. Conclusions: Novel functionalities of SMCC are presented in terms of sticking prevention while having the most beneficial effect on dissolution stability in R411 formulation.     

Adsorption of an amine drug onto microcrystalline cellulose and silicified microcrystalline cellulose samples

The adsorption of a model amine drug (tacrine hydrochloride) from aqueous solution onto 21 microcrystalline cellulose (MCC) based samples has been investigated. The MCC source (manufacturer) affected adsorption. The adsorption appeared to be fully reversible. Adsorption was reduced by the use of high-density grade MCC, high-energy milling, and silicification. Adsorption of the model drug was not affected by the particle size of the MCC. Significant variations of the adsorption characteristics between batches of certain MCC products were found. The primary mode of adsorption was by ion exchange.     

乙酸纤维素游离膜的吸湿性

研究了以乙酸纤维素为原料，丙酮为溶煤，用平面铸膜法制备的乙酸纤维素游离膜的吸湿性的特点．结果表明，游离膜的吸湿量和表观膜厚没有关系，仅与致密层厚度相关；增塑剂可增加膜的吸湿性，不同增塑剂对改善膜的吸湿性影响程度不同．     

高取代度氰乙基纤维素与二醋酸纤维素共混中空纤维纳滤膜的研制

采用高取代度氰乙基纤维素与二醋酸纤维素共混为膜材料,丙酮、二氧六环混合溶剂,以有机醇为主、加入适量其他添加剂为致孔剂,通过冰水凝胶浴干湿法纺丝,制得性能良好的中空纤维纳滤膜,该膜在给水质量浓度1 800 mg/L、操作压力为0.6 MPa、水温25℃条件下,对二价盐CaCl2、一价盐NaCl的水溶液的脱盐率分别大于90%和小于60%,水通量均大于3.5 mL/(cm2.h).还讨论了膜液的组成和纺丝条件对膜性能的影响.     

再生纤维素分离膜制备方法研究进展

再生纤维素分离膜具有高度亲水性,良好耐污染性,尤其是在环境中具有生物可降解性,对发展我国膜工业和保护环境都具有重要意义,介绍了近年来国内外再生纤维素分离膜测备过程的研究状况,主要针对制膜过程中采用的溶剂,添加剂,凝胶工艺以及改性方法进行了综述。     

超声波活化处理提高纤维素选择性氧化反应性能的研究

纤维素是一种重要的可再生性天然多糖聚合物。纤维素的高度结晶性和难溶性,决定了纤维素多数的化学反应都是在多相介质中进行。为了提高纤维素对试剂的可及度及反应性能,在进行多相反应之前,纤维素材料通常要经历溶胀或活化处理。本文采用超声波对纤维素进行活化处理,研究了处理条件对纤维素选择性氧化反应的影响。结果表明,超声波处理能显著提高纤维素与高碘酸盐的氧化反应活性,缩短反应时间和高碘酸盐用量,优化反应条件。     

纤维素接枝丙烯酰胺高吸水树脂的制备与表征

通过溶液聚合的方法,以丙烯酰胺和浆板制备了纤维素系高吸水树脂;研究了单体量、合成温度、引发剂量、交联剂量、水解浓度对树脂吸水能力的影响,并确定树脂的最佳制备条件为:浆板3g,单体量18g,交联剂量0.08g,引发剂量0.6g,合成温度70℃,水解浓度0.7mol/L,此时吸水倍率最高,达到633.3g/g;采用红外光谱(FT-IR)、X-射线衍射(XRD)、热重分析(TGA)和扫描电镜(SEM)分别对树脂进行表征并分析了高吸水树脂的结构。     

醋酸纤维素氨基甲酸酯膜材料的制备与表征

利用尿素对醋酸纤维素(CA)进行浸泡预处理,然后移入邻二甲苯惰性体系中进行反应,探讨合成过程中的影响因素,结果表明,预处理过程中尿素的质量分数为25%,预处理温度55℃,预处理时间5 h,反应时间3.5 h时,所得醋酸纤维素氨基甲酸酯(CAC)取代度可达到0.1.FT-IR表征可以证明成功合成出了CAC.用制备的CAC进行铸膜,CAC膜的拉伸强度及水通量要优于CA膜,同时研究得出随着取代度的升高,CAC膜的拉伸强度及水通量呈上升趋势.     

Observations on bacterial cellulose tube formation for application as vascular graft

Nanocellulose (bacterial cellulose, BC), such as that produced by Acetobacter xylinum, has shown promising results as a replacement material for small diameter vascular grafts. The surface morphology of the lumen and mechanical properties of such tubes are crucial for their performance. The growth of a BC tube in a vertical fermentation bioreactor using silicone tubing for support and as an oxygen delivery membrane has not been studied in detail previously. Oxygen concentration and the number of bacteria added influence the production of the BC tubes. A dense and smooth luminal surface was formed after 4 days on a 3 mm silicone support. The bacteria were found to be in high concentration close to the silicon support and decreased in number further away. In the region with a high bacteria concentration, dense thin layers of BC were formed since the bacteria moved close together in this region. The presented observations were summarized in a theoretical model of BC tube growth.