药物纤维及其在新型给药系统中的应用

综述了制备药物纤维的材料和技术以及药物纤维在新型给药系统(DDS)中的应用。分析了目前药物纤维DDS技术存在的问题。药物纤维可分为原料型、天然纤维的后整理型、聚合物型及复合型。其制备方法主要有传统纺丝方法、静电纺丝技术、非织造布技术以及后整理技术。指出中草药纤维的DDS、智能释药纤维DDS及多药多级控释DDS是今后药物纤维DDS研究的方向。     

环境友好的麦草制浆工艺

文章采用NH4OH-KOH-AQ对麦草进行蒸煮,系统研究了蒸煮液用量和配比、液固比、蒸煮最高温度、升温时间和保温时间对蒸煮效果的影响,继而确定了适宜工艺条件。结果表明,该蒸煮体系对麦草木素的脱除率达到85%,纸浆得率为49.65%。     

考虑地面积尘时置换通风的数值模拟

引言 置换通风系统始于北欧,较多应用于工业通风.近几年来,由于其合理的温度分布、较高的通风效率和明显的节能特性,置换通风系统已经越来越多地应用到民用建筑中.在北欧新建的办公建筑中,约有50%～70%的部分采用了置换通风系统[1].     

银鸽纸业公司五万吨竹溶解浆技改项目竣工

<正>四川银鸽竹浆纸业有限公司五万吨竹溶解浆技改项目已全面建成,进入最后调试和试生产阶段。2011年,四川银鸽竹浆纸业有限公司投资5亿元,启动实施了5万吨竹溶解浆技改项目,历时两年多时间,由超级间歇蒸煮、洗筛漂白、碱回收、浆板机四个项目为一体的5万吨竹溶解浆技改项目于近日全面建成。技改项目采用了低能耗的置换蒸煮技术、     

药物传导系统在化妆品中的应用

对于新兴的皮肤传导系统的搜寻应当作为皮肤研究中的焦点。目前，应用在个人护理产品的新兴方法大量地借鉴了药物的传导系统，甚至还包括一些新奇的方式如激光和超声波。下面介绍一下药物传导系统(DDS)     

基于DDS技术的涡流检测阻抗信号分解器的设计与实现

从原理出发推导出涡流检测系统所需的阻抗分解器的实现要求,首先分析了单通道直接数字合成(Direct Digital synthesis,DDS)技术应用于阻抗信号分解器中存在的问题,然后着重论述了基于多通道同步DDS技术的阻抗信号分解的设计方案和实现方法.实验和结果分析表明,基于多通道同步DDS技术的分解器设计从根本上解决了阻抗信号分解技术中的同步性及精度要求等难点问题,不仅提高了涡流检测系统的整体性能,还使系统集成度以及可操作性大为改善.     

置换式高压物性取样系统在海上油田探井测试中的探讨研究

对置换式高压物性取样系统进行了一定探讨,研究了置换式取样器、转样流程及装置和关键技术问题等,概括了置换式高压物性取样系统的作业优势。实践表明,该置换式高压物性取样系统能满足海上油田探井测试作业要求。     

安特威选型下单到成品出库全程仅需40分钟

正安特威自主研发的数字化交付系统(DDS系统)已实现全流程打通,这意味着质量控制实现实时可视、实时可控,甚至可以在紧急情况下进行远程生产。今后,安特威每个产品上都将有专属二维码,用户只要扫描二维码即可获取该阀门所有的信息,并解决实时质量控制问题。DDS系统让安特威质量控制再上新台阶,代表了国际领先水平!     

热泵蒸煮过程的分析与计算

本文对可应用于蒸煮过程的压缩式热泵和蒸汽喷射式热泵,进行了分析与计算,结果表明在蒸煮过程中采用热泵系统。能收到极显著的节能、节水效益;还表明应以整个供热系统的供热系数和一次能源利用系数来衡量各热泵系统的能量利用性。     

化工装置检修安全的应对措施

化工生产装置检修与其他行业的检修相比，具有复杂、危险性大的特点。尤其在装置停车及其吹扫、置换、蒸煮、清洗等环节工作的好坏，直接影响到装置检修能否安全顺利进行，是安全生产的重要环节，必须引起高度的重视。     

Dehydration by Successive Pressure Drops for Drying Paddy Rice Treated by Instant Controlled Pressure Drop

The aim of the present work was to study the application of the dehydration by successive pressure drops (DDS) process to different varieties of paddy rice initially treated by the instantaneous controlled pressure drop (DIC), which is a high-temperature, short time postharvest treatment (moisture content about 20–25% dry basis) and takes less than 30 s. DIC paddy rice is dried by DDS in a relatively short time and a high milling quality is obtained (12–13% db in about 2 h). The final rice is white, easily distinguishing it from the standard parboiled one. Without a tempering period, DDS rice has less than 3% of broken grains, with a high organoleptic quality (preservation of the natural aroma with a firm and non-sticky texture), and the cooking time of both brown (whole) and white DIC rice is very short (15 and 7 min, respectively).     

Dehydration by Successive Pressure Drops for Drying Paddy Rice Treated by Instant Controlled Pressure Drop

The aim of the present work was to study the application of the dehydration by successive pressure drops (DDS) process to different varieties of paddy rice initially treated by the instantaneous controlled pressure drop (DIC), which is a high-temperature, short time postharvest treatment (moisture content about 20-25% dry basis) and takes less than 30 s. DIC paddy rice is dried by DDS in a relatively short time and a high milling quality is obtained (12-13% db in about 2 h). The final rice is white, easily distinguishing it from the standard parboiled one. Without a tempering period, DDS rice has less than 3% of broken grains, with a high organoleptic quality (preservation of the natural aroma with a firm and non-sticky texture), and the cooking time of both brown (whole) and white DIC rice is very short (15 and 7 min, respectively).     

聚乙二醇支载紫杉醇给药系统的制备与抗癌活性

利用紫杉醇分子中2′-羟基较高的反应活性,将紫杉醇连接到经氨基酸修饰后的水溶性聚乙二醇（PEG）分子上,制得了新型紫杉醇给药系统（DDS）,测定了DDS的水溶性、紫杉醇含量及体外抗肿瘤活性.研究表明,此类系统水溶性良好（达紫杉醇的200～400倍）,对乳腺癌MCF-7细胞和非小细胞肺癌PG细胞有很强的抑制作用,效果与紫杉醇相当,表明上述方法是解决紫杉醇水溶性及给药方式问题的可能方法之一.     

Morphology,thermal and mechanical performance of epoxy/polysulfone composites improved by curing with two different aromatic diamines

Epoxy/polysufone (PSF) composites cured with 4,4'-diaminodiphenyl sulfone (DDS) and 4,4'-diaminodiphenyl methane (DDM) were fabricated, and the effect of dual curing reaction of diamines with epoxy on morphology, mechanical, and thermal performance was investigated. DSC results indicated that DDM was more reactive than DDS and the activation energy decreased with the rising of DDM content. Structures with small domain size at the early stage of phase separation were fixed by the fast epoxy-DDM reaction. When the DDM content was elevated to a high level, large dual structures were changed to fine bicontinuous structures, which was favorable to improve the mechanical property. The mechanical performance of epoxy composites was enhanced and the maximum values were achieved when the DDM/DDS ratio was located at 75/25 (PSF/DDS0.25-DDM0.75). The flexural and tensile strength relative to epoxy/DDM system were enhanced more than those relative to epoxy/DDS, while the increase in toughness was the opposite. TGA measurement showed that thermal stability of epoxy/PSF composites was improved because of the restricting effect of continuous PSF domains on thermal motion of epoxy. DMA analysis exhibited two relaxation peaks for PSF/DDS0.25-DDM0.75, which could be attributed to the formation of phase separated morphology and epoxy network with different cross-link density.     

Curing,compatibility, and fracture toughness for blends of bismaleimide and a tetrafunctional epoxy resin

The curing, compatibility, and fracture toughness of blends of 4,4 ′-bismaleimidodiphenylmethane (BDM)/tetraglycidyl diamino-diphenyl methane (TGDDM) were investigated. Diamino-diphenyl sulfone (DDS) was used as a curing agent. BDM alone could be both homopolymerized (at a lower temperature) and could also undergo Michael addition reactions with the primary amine of DDS. The secondary amine of DDS did not react with BDM. However, the network produced by homopolymerization was not miscible with that produced by the latter reactions. Curing of TGDDM with DDS took place almost at the same temperature as that of the homopolymerization of BDM, but well below the temperature of the Michael addition reaction. When a BDM/TGDDM mixture was cured with DDS in the stoichiometric ratio, the miscibility of the cured system increased with the amount of TGDDM. This was attributed to the fact that the network produced by Michael addition reactions was diminished. When DDS reacted entirely with TGDDM, the BDM/TGDDM/DDS cure yielded only a TGDDM/DDS network and a BDM homopolymerized network, which were not only miscible, but are also interpenetrating. The superior interpenetrated network, as indicated by the highest fracture toughness, was found at BDM/TGDDM = 40/60 weight ratio in the BDM/TGDDM/DDS curing systems.     

新型双马来酰亚胺改性环氧树脂体系性能研究

用含二氮杂萘联苯结构的双马来酰亚胺(DHPZ-BM I)与4,4'-二氨基二苯砜(DDS)为复合固化剂固化环氧树脂(E-51)。采用示差扫描量热仪(DSC)研究了该体系的固化反应动力学,求得固化反应表观活化能Ea=63.28 kJ/mol,碰撞因子A=1.55×106s-1,反应级数n=0.89,该体系与链延长型双马来酰亚胺PPEK-BM I(DP=15)/DDS/E-51体系的固化反应动力学数据几乎相同,证明二者的固化反应过程相同。采用热失重分析仪(TGA)分析研究了上述2种固化体系的热分解动力学,前者的热分解活化能达215.04 kJ/mol,为后者的1.5倍以上,说明DHPZ-BM I/DDS/E-51是1种热稳定性能良好的耐高温环氧树脂体系。     

Novel adamantane‐containing epoxy resin

A novel adamantane‐containing epoxy resin diglycidyl ether of bisphenol‐adamantane (DGEBAda) was successfully synthesized from 1,3‐bis(4‐hydroxyphenyl)adamantane by a one‐step method. The proposed structure of the epoxy resin was confirmed with Fourier transform infrared, ¹H‐NMR, gel permeation chromatography, and epoxy equivalent weight titration. The synthesized adamantane‐containing epoxy resin was cured with 4,4′‐diaminodiphenyl sulfone (DDS) and dicyandiamide (DICY). The thermal properties of the DDS‐cured epoxy were investigated with differential scanning calorimetry and thermogravimetric analysis (TGA). The dielectric properties of the DICY‐cured epoxy were determined from its dielectric spectrum. The obtained results were compared with those of commercially available diglycidyl ether of bisphenol A (DGEBA), a tetramethyl biphenol (TMBP)/epoxy system, and some other associated epoxy resins. According to the measured values, the glass‐transition temperature of the DGEBAda/DDS system (223°C) was higher than that of the DGEBA/DDS system and close to that of the TMBP/DDS system. TGA results showed that the DGEBAda/DDS system had a higher char yield (25.02%) and integral procedure decomposition temperature (850.7°C); however, the 5 wt % degradation temperature was lower than that of DDS‐cured DGEBA and TMBP. Moreover, DGEBAda/DDS had reduced moisture absorption and lower dielectric properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

环氧电工塑料的固化反应动力学研究

以双马来酰亚胺(BMI)/二氨基二苯砜(DDS)为组合固化剂,采用非等温示差扫描量热法(DSC)研究了邻甲酚醛环氧树脂(ECN)/DDS/BMI三元体系的固化反应动力学,用Kissinger法和Crane公式进行DSC数据处理,获得了固化反应动力学参数,并建立了固化动力学模型,同时结合红外光谱分析探讨了该体系的反应机理。结果表明,ECN/DDS/BMI体系固化反应级数n=0.93;表观活化能Ea=58.2 kJ/mol,与ECN/DDS体系相差很小,BMI的加入对体系的固化工艺影响不大,ECN/DDS/BMI体系的固化动力学模型与ECN/DDS体系相似。     

环境敏感型药物传送体系的研究进展

敏感性药物传送体系在药物控制释放领域的应用越来越广泛。根据刺激条件的不同,综述了pH响应型、温度响应型、光敏感型、氧化还原性响应型、葡萄糖响应型和磁场响应型等一系列刺激响应型药物传送体系的应用和研究进展。