用∑WESH图评价某涂料化工厂的可持续性

介绍了在清洁生产过程中用∑WESH图评价涂料化工厂的可持续发展的原理及方法,并进行了一个实例的评价.从该厂的∑WESH图得出该厂的水及能源的利用率高,所用的原材料的稀缺性都不大,唯一较严重的问题是二甲苯的通过量大,危害性较严重.因此建议该厂在配方上尽量减少二甲苯的使用,开发新产品.     

喷涂前处理污染源的分析及其处理措施

随着我国国民经济的快速发展和国家"节能减排"重点项目的深入开展,各种污染源的分析及其处理措施的研究备受关注.本文在充分研究若干家电企业的钢铁喷涂制件的前处理工艺(如:预脱脂、脱脂、清洗、表调、磷化等)的基础上,分析喷涂前处理过程中的污染源,研究污染源的处理措施.     

酿酒酵母细胞表达异源萜类化合物的研究进展

萜类化合物具有可观的经济价值,但是目前的生产过程复杂、产量低。酿酒酵母甲羟戊酸途径为萜类化合物的合成提供直接前体,因此酿酒酵母细胞具有合成异源萜类化合物的天然优势。对酿酒酵母甲羟戊酸途径的清晰认识是对其进行有效利用的基础,本文从代谢途径、关键酶的特点和全局调控机制3个方面对该途径进行了介绍。从代谢途径的构建和优化、模块与底盘细胞的适配、模块构建及组装方式的角度概述了酿酒酵母细胞异源合成单萜、倍半烯萜、二萜、三萜类化合物的研究进展。指出实现酿酒酵母高效合成萜类化合物所需要解决的基础问题是对酿酒酵母甲羟戊酸途径进行更为全面了解和对萜类化合物的天然代谢途径进行明确解析;另外,合成生物学的进一步发展也将为此提供应用基础。     

香叶油的研究进展

为了全面了解香叶油的研究现状,为我国香叶油的开发利用提供思路, 综述了香叶的栽培、组培技术研究、香叶油的应用、香叶油的提取及化学成分研究、香叶油调配研究等方面的现状,并对香叶品种的遗传改良提出一些有益的建议.     

胶原纤维的性能特点和作用

1胶原纤维巴西Novaprom胶原纤维是以精选的牛皮内剖层(真皮)组织提取的,它不同于明胶或明胶的衍生物。它的生产是在严格控制的时间和温度范围内进行的,从而确保其主要成分──胶原蛋白的活性不变,并以天然纤维的形式存在。它在肉制品中的结构呈纤维状而不是一般的胶冻,因而这种结构是非常稳定的,是不可逆的。它是很好的功能性动物纤维蛋白,在肉制品及鱼糜制品等相关的食品中得到广泛的应用。2胶原纤维的性能及相关指标(1)蛋白质含量:胶原纤维中的动物蛋白质(M×6.25)高达98%,含有人体必需的氨基酸。(2)吸水、持水性:胶原纤维结构良好,呈矩…     

鲜为人知的科学珍闻

有言在先,珍闻的挑选奉行以下原则:科学应该是有趣的,科学之所以好玩,部分原因在于你了解、知道这些奇谈怪论的存在。科学的伟大之处在于,它不必是教条的、有价值的实验,也不要求对所有理论进行最准确的过滤以得     

玻璃纤维拉丝池窑配合料设备研制的进展

玻璃纤维池窑拉丝生产线配合料的制备中,原料是形成优质玻璃液的基础,因此可以说配合料的稳定性、均匀性和准确性对玻璃纤维的质量起着决定的作用.生产实践证明:组分和粒度均匀的配合料,不但能强化玻璃液的熔化和澄清过程,而且还能减少或消除影响玻璃质量的各种弊病.所以认真拟定玻璃纤维原料的成分和选择玻璃纤维的种类和化学性质:严格控制进厂原料化学成分、粒度和水份;做好原料的分堆、存放、加工、称量、混合、输送是优质配合料制备不可缺少的手段,这也是做好玻璃纤维池窑配合料的基本任务.     

氢氧化镁阻燃剂的研究进展

主要论述了国内外阻燃剂的种类和发展,指出由于环境和健康的原因,无机阻燃剂是最有发展前途的,其中的氢氧化镁因其特有的性质,在无机阻燃剂中尤为突出.考虑到氢氧化镁的广泛应用的前景和其本身的缺点,对其改性成为业界的研究重点,其中主要介绍了钛酸酯、硬脂酸(盐)、镁盐晶须和胶囊化等技术,指出以后的发展方向是在改性基础上的协同作用.     

高浸透性大分子聚酯乳液的研制

1前言 随着池窑生产的发展,原有的浸润剂在快速浸润性和快速浸透性方面无法得到满足.意大利DSM公司聚酯乳液是公认的喷射纱浸润剂最好的成膜剂.本项目的目的是研制出能工业化生产的与DSM公司产品质量相当的聚酯乳液,替代进口,节约外汇,满足我国池窑发展需要,争创良好的经济社会效益.     

宁静——使艺术深华

宁静的山是心灵的绘画,宁静的水是灵魂的诗篇,宁静的夜是精神的书籍。在这越来越充斥着物欲纵横的社会,浮躁成了现代人的代名词,而保持一颗宁静的心,尤其在艺术创作中显得尤为重要。     

Scaling-up of instantaneous data of complex kinetics

Kinetic data related to complex mixtures of reactants and catalysts are necessary to simulate design and rate industrial chemical reactors. In the particular case of Fluidised-bed Catalytic Cracking, the main reaction takes place in riser reactors; whereas laboratory data are obtained in small fixed bed reactors. Even though this important difference in size and hydrodynamics, laboratory reactors are used to estimate, accurately, yield to products and apparent activation energies of the reactions proposed; however estimated frequency factors are very different from the ones observed at industrial reactors. In this work a scaling-up of frequency factors is performed, assuming that activation energies estimated in laboratory are correct. The adjusting effort is minimised because it is necessary to scale-up only one of the reaction rates and the rest of them are fitted proportionally to the first one. A 5-lump kinetic scheme for catalytic cracking of vacuum gas oils is used to test this approach; prediction obtained for industrial yields is very accurate.     

茚酮化合物合成方法研究进展

茚酮化合物广泛存在于许多天然产物中,这类化合物具有多种生理活性,是重要的有机合成中间体,广泛应用于医药、农药、染料的合成等。本文重点介绍了环化法合成茚酮化合物,其中分子内傅雷德尔-克瑞福斯（Friedel-Crafts）环化法是茚酮化合物的经典合成法,该法优点是技术成熟,后处理较简单,易于工业化,但该方法产生大量的含铝废液,对环境造成污染。同时,文章对近年来出现的新的茚酮化合物合成方法,如重排法、光化法等进行了对比讨论,新方法与经典合成法相比,具有条件温和、步骤少、产物纯度高等优点,但受到所用原材料等条件的限制,其工业化进程不易实现。通过对近十几年来茚酮化合物合成方法的系统化讨论,指出开发绿色环保、原子经济、易于工业化的新的茚酮化合物合成方法是今后研究的重点。     

Verification of numerical simulation of the self-assembly of polymer-polymer-solvent ternary blends on a heterogeneously functionalized substrate

The directed self-assembly of polymer-polymer-solvent ternary blends on heterogeneously functionalized substrate is investigated with a three dimensional numerical model. The numerical simulation results are quantitatively verified by the experimental results. The phase separation of PS-PMMA-DMF blends are spin coated on a substrate functionalized by ODT/₂NH on Au surface. While many simulation parameters are set to the experimental conditions, other unmeasurable material constitutive model parameters are estimated from the real experiment observations. The effects of the spin speed, pattern periodicity, PS/PAA composition ratio, and the PAA molecular weight are investigated in both the experiments and numerical simulation. The simulation results are verified by comparison to the experimental results. During the verification process, numerical optimization methods are employed to determine the unmeasurable physical parameters. Quantitative methods are introduced for assessment of the results.     

Effects of the amount of fillers and of the crosslink density on the mechanical behavior of carbon‐black filled styrene butadiene rubbers

Several carbon‐black filled styrene‐butadiene rubbers are subjected to monotonic uniaxial tension tests in order to investigate the effects of the amount of fillers and of the crosslink density on their mechanical properties. The Young modulus, the volume changes associated with material damage and the stretch to failure are extracted and discussed. Results compare well to the literature results when exist and quantitative analysis are proposed when possible. Results show that filled rubbers are not incompressible when submitted to uniaxial tension tests and their volume changes are strongly dependent of the amount of fillers but are unaffected by the crosslink density. The latter shows strong impact on the filled rubbers stretch to failure but more interestingly this impact is comparable to what is encountered in unfilled rubbers. The stretch to failure is improved by the addition of fillers with an optimum for material filled around 30 phr. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

杀虫抗生素的发展概况与展望

杀虫抗生素是生物源杀虫剂,具有高效、低毒、选择性强、对环境无公害等特点,在害虫综合治理中有重要地位,是无公害作物中首选农药之一。作者就杀虫抗生素的品种开发情况进行了阐述,对杀虫素的杀虫机理、抗性机制及进一步加大研究开发力度等问题进行了讨论。     

壬基酚变色综合分析

本文详细分析了壬基酚变色的原因，并提出了有效防止比色指数上升的措施，应用效果显著。本文同时提出了新的问题。     

Polymers of phenylenediamines

The chemical or electrochemical oxidation of phenylenediamines in acidic aqueous media yields the corresponding oligomers or polymers. Their structures and properties are discussed in relation to a closely-related conducting polymer, polyaniline. Depending on the reaction conditions, polyphenylenediamines are produced as powders, colloidal dispersions, thin films, or composites. In contrast to polyaniline, polyphenylenediamines are rated as non-conductors and their conductivities are low. Similarly to polyaniline, these polymers display a salt–base transition and they are redox-active. They act as reductants of noble-metal compounds to the corresponding metals or as precursors in the carbonization to nitrogen-rich carbons. Applications proposed in the literature are outlined; they include the corrosion protection of metals, catalysis, electrorheology, sensors, energy-conversion devices, electrochromism, noble-metal recovery, and water treatment.     

智能膜材料研究新进展

能感知和响应外界物理和化学信号的智能膜是仿生功能膜领域的重要技术进展之一,已成为国际上膜科学领域研究的新热点。本文综述了智能膜材料方面的研究新进展,重点介绍了温度响应型、pH响应型、光响应型、葡萄糖浓度响应型以及分子识别响应型等环境刺激响应型智能膜的研究进展。     

γ-巯丙基三乙氧基硅烷水解程度对纳米二氧化硅接枝机理影响的DFT研究

为探索γ-巯丙基三乙氧基硅烷(MPTS)水解程度对纳米二氧化硅接枝机理的影响，采用基于密度泛函理论(DFT)的量子化学方法，选择合适的泛函和合理的模型，系统研究了MPTS及其不同水解程度产物的反应活性及与纳米二氧化硅的接枝机理，为纳米二氧化硅改性工艺优化及改性效果的提升提供重要理论基础。结果表明：经数据对比确定GGA-PBE泛函优化后的纳米二氧化硅团簇模型为最合理模型。二氧化硅表面硅羟基中的氧原子为亲核活性中心，氢原子为亲电活性中心，MPTS及其水解产物中氧原子为亲核活性中心，硅原子为亲电活性中心。水解引起LUMO轨道向硅原子偏移，硅原子亲电指数提高，而HOMO轨道向氧原子偏移，氧原子的亲核指数提高，引起MPTS水解产物更容易受到二氧化硅表面硅羟基攻击，进而提高了接枝反应活性。MPTS的水解降低了接枝反应的活化能，不同水解程度产物接枝反应活化能(E _a)顺序为M0＞M3＞M1＞M2(M0、M1、M2和M3分别表示MPTS及其一级、二级和三级水解产物)，接枝反应属于S_N2亲核取代，且为放热反应。M0、M1和M2都是通过脱醇机理发生接枝反应，空间位阻效应和偶联剂中心硅原子的亲电性能为反应主要控制因素，而M3是通过脱水机理发生接枝反应。     

Assessment of the wettability of pharmaceutical powders

There is considerable interest in the assessment of the wettability of pharmaceutical powders, as the data can be used to give indications of product performance (in terms of a crude predictor of rates of drug release from dosage forms, or as a guide to the interfacial interactions between components of a formulation). However, contact angle methods for powders are problematic, in particular because powders have heterogeneous and rough surfaces, and these are often capable of rapid changes in properties. The different approaches to contact angle assessment are reviewed, and some advantages of vapour sorption experiments are discused.