医学专业物理化学教学改革的探索

结合多年的教学实践,分析了医学专业物理化学教学的现状和存在的主要问题,并对物理化学教学进行了改革和探索。改变了传统的教学模式,搭建了一个新的教学平台,增强了学生学习的主观能动性,提高了学生的学习效率和质量,培养了学生的创新意识和创新能力,取得了较好的教学效果。     

物理化学实验课教学模式的改革与实践

分析了目前物理化学实验课的教学现状和教学中存在的主要问题,并对物理化学实验教学进行了改革和探索。改变了传统的实验教学模式,搭建了物理化学实验教学网络平台,增强了学生学习的主动性,提高了学生的实验效率和实验质量,培养了学生的创新意识和创新能力,收到了良好的教学效果。     

二甲醚作为二次能源的前景分析

论述了二甲醚作为二次能源替代民用燃料和车用燃料的可行性和重大意义,阐述了我国能源短缺的危害和开发二次能源的必要性和紧迫性,简述了二甲醚的性质和制备,分析了二甲醚作为二次新能源开发的资源优势和对环境的重大意义及开发前景。     

汽油清洗机器爆燃致多入伤亡事故的原因剖析

简要介绍了某设备制造公司装配油漆工段发生燃爆事故的经过,详细描述了现场勘查过程和发现,通过勘查,详细分析了造成事故的直接原因和间接原因,并界定了事故责任和处理意见,提出了整改措施。     

苯加氢催化剂研究进展

介绍了苯加氢催化剂的分类,综述了均相催化剂、多相催化剂和离子液体催化剂的研究进展和生产工艺情况,其中多相催化剂可以对苯进行液相加氢和气相加氢。对苯加氢催化剂的评价和分析方法做了综述,讨论了苯加氢催化剂的加氢机理,对催化剂表面的吸附方式、反应速率的控制、苯和氢吸附的形式和分类问题做了说明。     

哈尔乌素选煤厂采用TDS智能干选机的改造及安全生产措施

介绍了TDS智能干选机在哈尔乌素选煤厂的应用现状及现场改造实践,从技术和管理方面提出了安全生产措施,改造后增强了选煤厂系统灵活性和市场适应性,降低了生产费用,稳定了煤质,保证了安全生产,提高了盈利能力,同时确保了生产工人辐射剂量小于一般公众限值,防爆和除尘满足规范和规程要求及煤矿安全生产要求。     

烟气脱硫脱硝技术发展分析

本文介绍了烟气脱硫脱硝技术的研究现状,从干法和湿法两方面介绍了脱硫脱硝领域的各项技术,对技术脉络进行了梳理,总结和分析了各项技术的优缺点和适应性,并对我国脱硫脱硝技术发展方向和前景进行了展望,为国内烟气脱硫脱硝技术的发展提供了参考。     

对二甲苯储存输转中的环境风险评估与管控研究

随着工业化的快速发展和化学品使用量的不断增加,对二甲苯储存输转中的环境风险成了一个亟待解决的问题。本文首先介绍了环境风险评估的概念和流程,然后探讨了对二甲苯储存输转中可能存在的环境风险,并阐述了环境风险评估的方法和实现。接着,文章分析了风险管控的基本原则,提出了对二甲苯储存输转中的风险管控策略,并结合实践案例进行了分析。最后,总结了对二甲苯在储存输转中的环境风险评估与管控的现状和不足,并提出了相关改进和建议。     

PVDF与PES滤芯对液体质量的影响分析

本文以不同材质的除菌过滤滤芯为对象,以溶液酸碱度为指标,探究了滤芯材质与操作参数对液体质量的交互作用规律,并取得了一定的成果。本文的创新点和成果主要有：采用了成品滤芯（PVDF孔径0.22mm,PES孔径0.22mm+0.45mm）,避免了自制滤芯的不稳定性和不可重复性;分析了疫苗生产中常见的不同性质的液体,如蛋白溶液、盐溶液、缓冲液和培养液,考察了它们的酸碱度、电导率、吸光度等参数,反映了液体的物理、化学和生物学特性;测试了滤芯与液体的交互作用,包括过滤通量和酸碱度变化率,揭示了滤芯材质、操作参数和液体性质对液体质量的影响,为过滤器的选择和操作参数的调节提供了依据;综合评价了PVDF滤芯和PES滤芯的优缺点,提出了适合不同液体的过滤方案,为疫苗生产中的液体过滤和净化提供了参考。     

搅拌器的选择和设计

本文对搅拌器选择和设计方法进行了分析,提出了应用于各种粘度的主要搅拌器叶轮的应用实例和经验,讨论了搅拦器设计和放大时各参数的选择和关系,为搅拌器的选型和设计提供了基础数据。     

B-O2催化剂上丁烯氧化脱氢动力学研究

本文利用内循环无梯度反应器,在320～420℃及较宽的各组分分压范围内研究了B-02工业催化剂用于丁烯氧化脱氢反应的本征动力学.按照串-并联反应网络,依据Redox机理、L-H机理和幂函数型规律构想出28个动力学模型;应用模型参数的物理特征、参数估值中的残差平方和相对大小以及非本征参数法筛选模型;采用模式探测法和马垮特法相结合的综合方法进行模型参数估值,从而求得适宜的本征动力学模型.最后对所定动力学模型进行显著性检验,证明该模型对实验数据确有较好的表现力.文中还讨论了水/烯比值对模型参数的影响、丁二烯的阻碍作用及催化剂的选择性等问题.     

Influence of comonomer incorporation on morphology and thermal and mechanical properties of blends based upon isotactic metallocene–polypropene and random ethene/1‐butene copolymers

Blends of isotactic polypropene (i‐PP) with random ethene/1‐butene (EB) copolymers containing 10, 24, 48, 58, 62, 82, and 90 wt % 1‐butene were prepared in order to examine the influence of the EB molecular architecture on the morphology development as well as on the thermal and mechanical properties. Compatibility between i‐PP and EB increased with increasing 1‐butene content in EB to afford single‐phase blends at a 1‐butene content exceeding 82 wt %. The morphology was investigated using AFM and TEM. Improved compatibility accounted for enhanced EB dispersion and interfacial adhesion. Highly flexible as well as stiff blends with improved toughness were obtained. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 838–848, 1999     

Dimerization of 1‐butene via zirconium‐based Ziegler–Natta catalyst

A zirconium‐based Ziegler–Natta catalytic system has been tested in the dimerization of 1‐butene. It was found that the concentration of Et₂AlCl, Ph₃P and PhONa as well as the reaction temperature had great influences on the activity and selectivity of the catalyst. Under the optimum reaction conditions, the conversion of 1‐butene is 91.9%, and the selectivity of dimers is 76.7%. Basic ligands such as Ph₃P and PhONa can inhibit isomerization of 1‐butene to 2‐butene effectively. In addition, the metal hydride mechanism was also suggested and some indirect evidence was obtained in favor of this mechanism. This revised version was published online in July 2006 with corrections to the Cover Date.     

异丁烷与丁烯烷基化反应用新分子筛催化剂的研究

探讨了六方沸石分子筛催化剂对异丁烷与丁烯烷基化反应的催化活性。实验确定了烷基化反应的温度、反应时间、异丁烷与丁烯摩尔比及反应压力对丁烯转化率及目的产物Ｃ０８ 的选择性的影响。并对各种参数的影响进行了简要分析。在适宜反应条件下,丁烯的转化率达到９８％ ,对Ｃ０８ 的选择性接近９３ ％ 。还进行了催化剂的物性测定,利用红外光谱和ＴＰＤ 氨脱附表征了催化剂表面酸中心性质及酸强度。测定结果表明,该催化剂具有大的比表面积,较多的酸中心和较高的酸强度,因而对异丁烷与丁烯的烷基化具有较高的催化活性。     

IR study on the reaction path of skeletal isomerization of 1‐butene

The reaction molecularity of the skeletal isomerization on zeolite was deduced from IR spectra of adsorbed butene recorded with heating. Formation of polymeric species from adsorbed butene was observed on ZSM‐5 and beta zeolites, non‐selective catalysts for isobutene production. On the other hand, most of butene molecules adsorbed on ferrierite and clinoptilolite behaved monomolecularly, resulting in complete desorption even at ambient temperature. The exceptional selectivity for isobutene of ferrierite and clinoptilolite was ascribed to the sparse distribution of adsorbed butene molecules, suppressing bimolecular oligomerization and enhancing monomolecular skeletal isomerization. This revised version was published online in July 2006 with corrections to the Cover Date.     

Epoxidation of a Series of C2–C6 Olefins in the Gas Phase

Epoxidation of ethylene, propylene, 2‐methylpropene, trans‐2‐butene, 2‐methyl‐2‐butene, and 2,3‐dimethyl‐2‐butene were carried out in a flow‐through reactor in the homogeneous gas phase at pressures of 0.25–1.0 bar in the temperature range of 250–375 °C. Residence times in the reactor varied from 8.3 to 38 ms. The oxidizing agent needed in the feed gas is ozone. The O₃ efficiency (reacted olefin/initial O₃) was found to be strongly dependent on the reactivity of the olefin used. For C₄–C₆ olefins, the O₃ efficiency was better than 75 % in each case. For 2‐methyl‐2‐butene and 2,3‐dimethyl‐2‐butene, the O₃ efficiency exceeded the theoretical value of 100 % considerably. The selectivity to epoxide was about 90 % independent of the olefin used. Under conditions of nearly total olefin conversion, the high selectivity to the epoxide has been retained as unchanged. There were no indications for consecutive reactions of the epoxides.     

用序贯实验设计法研究B02催化剂上丁烯氧化脱氢动力学

<正> 该催化剂虽已用于工业装置,但基本动力学数据的研究尚不充分,陈曙等利用外循环无梯度反应器,获得了该反应网络的半经验方程。作者应用经典方法由可能的28个候选模型中选出了较适宜的机理性模型。但由于经典法的实验安排是任意的,具有一定的盲目性,不保证每个实验数据均能充分反映模型之间的差别,实验测得数据虽很多,但有效数据较少。因而,筛选所得模型只是较适宜的,而不是最佳的。     

Study of propylene‐1‐butene‐ethylene terpolymer and reactor blend by TREF and 13C‐NMR

A terpolymer of propylene‐1‐butene‐ethylene (TERPO) and a reactor mixture of TERPO with an ethylene‐1‐butene copolymer (BLEND) were completely characterized by TREF, ¹³C‐NMR, DSC, and GPC, from which special equations for quantitative ¹³C‐NMR were derived. TERPO was shown to be composed mainly of highly isotactic propene and similar amounts of ethylene and 1‐butene. BLEND fractions were composed of variable amounts of TERPO and a random copolymer of ethylene‐1‐butene. The blend of TERPO and copolymer acts as two independent phases, each having its own elution temperatures dependent only on its crystallizability, itself only influenced by the comonomer content. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1880–1890, 2001     

Butene Catalytic Cracking to Propene and Ethene over Potassium Modified ZSM-5 Catalysts

Catalytic cracking of butene over potassium modified ZSM-5 catalysts was carried out in a fixed-bed microreactor. By increasing the K loading on the ZSM-5, butene conversion and ethene selectivity decreased almost linearly, while propene selectivity increased first, then passed through a maximum (about 50% selectivity) with the addition of ca. 0.7–1.0% K, and then decreased slowly with further increasing of the K loading. The reaction conditions were 620 °C, WHSV 3.5 h⁻¹, 0.1 MPa 1-butene partial pressure and 1 h of time on stream. Both by potassium modification of the ZSM-5 zeolite and by N₂ addition in the butene feed could enhance the selectivity towards propene effectively, but the catalyst stability did not show any improvement. On the other hand, addition of water to the butene feed could not only increase the butene conversion, but also improve the stability of the 0.7%K/ZSM-5 catalyst due to the effective removal of the coke formed, as demonstrated by the TPO spectra. XRD results indicated that the ZSM-5 structure of the 0.07% K/ZSM-5 catalyst was not destroyed even under this serious condition of adding water at 620 °C.     

Liquid Pool Copolymerization of Propylene/1‐Butene with a MgCl2‐Supported Ziegler‐Natta Catalyst

Summary: Liquid pool propylene/1‐butene copolymerizations were carried out in a batch reactor with a high activity Ziegler‐Natta catalyst system. Experimental runs were performed to evaluate the effect of the 1‐butene content on the crystallinity and melt temperature of the polymer resins. According to the results, 1‐butene can be significantly incorporated into the polymer chain at high polymerization rates over the whole range of copolymer compositions, leading to a decrease in the melting temperature (T_m) of the polymer, when compared to the poly(propylene) homopolymer, allowing for reduction of the sealing initiation temperature. It was observed by GPC and MFI measurements that the average molecular weights and the polydispersity index of the copolymer significantly decreased when compared to the ones obtained from poly(propylene). Despite high polymerization rates, polymer particles with good morphological features were produced in all cases. It was also observed that the absence of an external electron donor led to low crystallinity values for both the poly(propylene) homopolymer and for copolymers with different fractions of 1‐butene, when compared to literature values frequently reported for polymer resins based on 1‐butene and propylene. The obtained results indicate that a family of bulk propylene/1‐butene copolymer grades can be successfully developed for packaging and film applications.

Surface morphology and molecular weight distribution (deconvoluted into Schulz‐Flory distributions) of the propylene/1‐butene copolymer.