某厂生石灰粉贮运系统优化配置实例

以我国西南某钢铁厂烟气脱硫装置的生石灰粉贮运系统为例，根据当地气候特点结合生石灰粉料的物料性质，对该贮运系统进行了优化配置，如生石灰粉料仓采用双曲线圆形钢筒仓，并配置了钢筒仓保温、定量给料设备、流化设备，较好的解决了因生石灰粉贮运过程中吸潮、结拱等问题。     

碳钢槽车贮运DMF前的清洗

无防护处理的碳钢槽车，经过化学清洗可以用来贮运二甲基甲酰胺（ＤＭＦ）运行结果表明其贮运质量是稳定的。     

浓硝酸生产,检修,贮运安全浅析

分析浓硝酸生产，检修、贮运的事故原因及危险性，提出安全防范措施。     

岳阳煤气化合资厂煤贮运系统方案比较

鉴于目前国内原材料、动力价格上调，化肥价格下降的情况，一些大型化肥企业纷纷进行合成氨工艺原料路线的技术改造，以降低产品成本。介绍了岳阳煤气化合资厂以煤替代石脑油为原料，采用“粉煤加压气化”技术的合成氨装置煤贮运系统的两种方案，经过分析比较，决定采用系统可靠性高、流程灵活、建设投资低、卸车方式为螺旋卸车机配卸煤地槽的煤贮运系统方案。     

吉化乙烯厂石脑油卸车及贮运项目建成投用

吉化乙烯厂４０万ｔ／ａ石脑油卸车及贮运项目于１９９９年４月２６日全面建成投用，整个项目历时４５天结束，比原计划提前５天竣工。石脑油卸车及贮运项目是吉化公司今年重点项目之一，是乙烯厂独立运作后第一个基建项目。乙烯裂解炉以石脑油替换化工轻油可增加炼油厂出厂柴油量，今年可为公司增创上千万元效益，为此工厂高度重视，专门成立项目经理部，同公司基建管理部一道统筹安排、精心组织协调，在化建公司、铁运公司、设计院等单位的通力合作下，该项目得以顺利交付使用。石脑油卸车及贮运项目于１９９９年３月１２日破土动工，４月…     

交联剂DCP的分解研究及其预防

分析了交联剂ＤＣＰ在生产和贮运过程中的分解条件和现象，提出了预防措施和改进意见。     

应用汽车槽车贮运炭黑的探讨

炭黑是橡胶厂用量较大的一种主要配料。由于它体轻、易飞扬,在贮运及输送的过程中,极易污染环境。采用全密闭化炭黑贮运和输送系统,是保护环境,免除工业污染的主要措施。一、全密闭化炭黑贮运及输送系     

丙酮氰醇贮运可行性初探

本文在指出甲基丙烯酸甲酯单体的中间体—丙酮氰醇贮运意义的基础上,进行了静、动态模拟试验,探讨了贮运影响因素温度、时间和硫酸稳定剂的影响,取得了初步结果,为对丙酮氰醇这种有毒化学品贮运,提出了具体建议和要求。     

抽油杆防腐蚀涂料

一、前言抽油杆是采油机械的主要部件。八十年代前,我国各抽油杆生产厂均采用裸杆贮运。由于贮运时间较长,贮运条件又差,致使不少抽油杆上井时已经生锈,有的甚至出现蚀点和蚀坑。杆的这种不均匀腐蚀,使其在工作时往往应力集中而造成断裂,影响采油的正常进行。为此,我们受玉门石油管理局机械厂的委托,开展了抽油杆贮运过程中     

过氧化氢生产与贮运安全注意事项

介绍过氧化氢的安全与危险性，蒽醌制备过氧化氢工艺和设备设计中采取的安全措施，过氧化氢生产与贮运中安全事故避免措施及注意事项。     

Preparation and characterization of poly (vinyl chloride)-blend-poly (carbonate) heterogeneous cation exchange membrane: Investigation of solvent type and ratio effects

In this research polyvinylchloride/polycarbonate blend heterogeneous cation exchange membranes were prepared by solution casting technique using cation exchange resin powder as functional groups agent. Tetrahydrofuran (THF) and dimethylformamide (DMF) were utilized as solvents. The effect of solvent type and ratio (THF/DMF mixture) on properties of prepared membranes was studied. SEM and SOM images showed relatively uniform particle distribution and also uniform surface for the membranes. Images showed that at high DMF ratio decrease of polymer conformation with particles surface reduces the compatibility of polymer-particle. The membrane ion exchange capacity and permeability were enhanced initially by increase of DMF ratio up to 5% (v/v) in casting solution and then they began to decrease with more DMF ratio. Results showed that membrane potential, transport number, selectivity and thermal stability all were decreased by DMF ratio increasing. Conversely, membrane water content, specific surface area and roughness showed opposite trends. Membrane electrical resistance initially declined by increase in DMF content up to 15% (v/v) and then it began to increase. The increase of electrolyte concentration also led to decrease in membrane transport number and selectivity. Membrane with (95:5) (v/v) solvent ratio (THF:DMF) exhibited more appropriate performance compared to others.     

Active transport of alkali metal ion through a membrane composed of gluconolactone-containing polymer

Summary The membrane composed of gluconolactone-containing polymer was prepared by the following three steps, (1) the copolymerization between acrylonitrile and a styrene derivative carrying a protected glucose substituent, (2) casting a membrane from the DMF solution of the copolymer, and (3) a sequence of reactions for the membrane. It exhibited active transport of Na⁺ ion against the concentration gradient.     

溶剂的性质对聚砜／磺化聚砜合金膜性能的影响

介绍了溶剂的性质对聚砜 /磺化聚砜 (PSF/SPSF)合金分离膜膜性能的影响     

聚丙烯腈纤维生产中溶剂塔塔顶液未知物的分析

干法腈纶生产中,对回收提纯二甲基甲酰胺(DMF)的溶剂塔进行技术改造之后,溶剂塔塔顶液的气相色谱图上出现非DMF的未知物质。用气相色谱法对未知物进行定性和定量分析,确定该物质为DMF的分解产物三甲胺。此分析为设备改造后生产中DMF消耗严重超标找到了原因,为进一步完善和改造提供了依据。     

Multi-element determinations of N,N-dimethylformamide (DMF) coal slurries using ICP-OES

A slurry nebulisation technique was applied for elemental analysis of bituminous coals SARM 18, SARM 19 and four coals from three different seams in Witbank, South Africa, by inductively coupled plasma optical emission spectroscopy (ICP-OES). Major elements (Al, Ca, Fe, Mg, S, Si and Ti) and trace elements (Ba, Cr, Mn, Ni, Sr, V, Zn and Zr) in coal were determined. Various slurry preparations were evaluated using two dispersants (glycerol and Triton X-100) and by varying the concentration of dispersants, between 0.1% and 1.0% (v/v). The effect of initially solubilising the ground coal in N,N-dimethylformamide (DMF) was investigated by varying the volume of DMF added. The effect of wet grinding with DMF was investigated. Wet grinding with DMF was shown to drastically reduce particle sizes (50.0% < 0.28 μm and 90.0% < 6.17 μm) as compared to dry grinding (50.0% < 5.25 μm and 90.0% < 11.1 μm). The reduced particle sizes and increased transport efficiency of the coal slurries led to improved analytical recoveries of elements in the reference coal, SARM 18. The best analytical recoveries for all elements were achieved using 0.1% Triton X-100 with 10.0% DMF. Results obtained by ICP-OES after wet grinding of the coal with DMF, using 0.1% Triton X-100, also gave excellent recoveries (Al, 100%; Ca, 103%; Cr, 106%; Fe, 102%; Mg, 100%; Mn, 104%; Ni, 109%; Si, 102%; Ti, 95.0%; and V, 108%). The results obtained with 10.0% DMF and 0.1% Triton X-100 were in agreement with certified values for all selected elements according to paired t-test at the 95.0% confidence level. Selected elements (Al, Ca, Fe, Mg, Mn, Si, Ti and V) were also analysed with X-ray fluorescence for comparison with results obtained from ICP-OES. Analysis by ICP-OES of microwave digested coal was also carried out. It is suggested that the DMF slurry technique could be used for routine analysis of bituminous coals.     

非均相催化剂催化5-羟甲基糠醛氢解制备2,5-二甲基呋喃研究进展

随着化石能源的日益短缺,清洁可再生生物质资源的利用,尤其是制备高品质生物燃料逐渐成为研究热点。2,5-二甲基呋喃（DMF）具有优良的物理化学性质,被认为是最有前途的液体生物燃料之一,可通过生物质平台分子5-羟甲基糠醛（HMF）选择性氢解制备。HMF化学性质非常活泼,可以转化成多种下游产品,因此设计制备高选择性催化剂对于靶向合成DMF至关重要。本文依据贵金属和非贵金属对催化剂进行分类,详细综述了非均相催化剂在HMF氢解制备DMF反应中的研究新进展;针对目前研究中存在的局限性和问题,提出了催化剂和反应体系的研究方向。此外,指出以生物质为原料直接制备DMF及建立有效的分离技术是实现DMF工业化生产的重要途径。     

Dimethyl Fumarate Promotes the Survival of Retinal Ganglion Cells after Optic Nerve Injury,Possibly through the Nrf2/HO-1 Pathway

This study aimed to verify whether dimethyl fumarate (DMF) promotes the survival of retinal ganglion cells (RGCs) after optic nerve crush (ONC) accompanied by activation of the NF-E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. We examined changes in the densities of tubulin β3 (TUBB3)-positive RGCs and the amplitudes of the positive scotopic threshold response (pSTR), reflecting the functional activity of RGCs, recorded on an electroretinogram, with daily administration of DMF, on day 7 after ONC. Furthermore, immunohistochemical and immunoblotting analyses were performed to study the activation of the Nrf2/HO-1 pathway using retinas treated with daily administration of DMF. Daily administration of DMF increasedthe density of TUBB3-positive RGCs in a dose-dependent fashion and significantly increased the amplitude of the pSTR. Immunohistochemical analysis showed that DMF administration increased the immunoreactivity for Nrf2 and HO-1, a potent antioxidant enzyme, in RGCs immunolabeled with RNA-binding protein with multiple splicing (RBPMS). Immunoblotting analysis revealed an increase in the nuclear expression of Nrf2 and marked upregulation of HO-1 after DMF administration. These results suggest that DMF has survival-promoting effects in RGC after ONC, possibly via the Nrf2/HO-1 pathway.     

Effect of addition of surfactants on the rheology of gels from methylcellulose in N,N‐dimethylformamide

The effect of highly substituted cationic cetyl trimethyl ammonium bromide (CTAB), less substituted cationic hexadodecyl ammonium bromide (HDAB), CTAB‐ and HDAB‐modified montmorillonite (CTABMONT and HDABMONT), and nonionic surfactants on the rheological properties of methylcellulose (MC) N,N‐dimethylformamide (DMF) gels have been studied. The storage modulus of the MC‐MDF gels increases with an increase in frequency. During the frequency scan, the storage and loss modulus of MC‐DMF gel crosses over each other at two different frequencies. At the crossover points, the loss tangent is found to be unity. The addition of CTAB‐ and HDAB‐modified nanofiller increases in the gel strength of MC‐DMF gel. The storage modulus of MC‐DMF gel in the presence of CTABMONT is found to be higher than that of CTAB‐modified MC‐DMF gel. Whereas, the storage modulus of MC‐DMF gel in the presence of HDABMONT is lower than that of HDAB‐modified MC‐DMF gel. On the other hand, the addition of nonionic surfactant (Brij78) decreases the gel strength. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

N,N‐Dimethylformamide Additions to the Solution for the Electrospinning of Poly(ε‐caprolactone) Nanofibers

Summary: Additives that exhibit polyelectrolyte behavior such as N,N‐dimethylformamide (DMF) may improve the electrospinning characteristics of viscoelastic polymer solutions. DMF additions to the solution lead to extensive jet splaying, thereby reducing the fiber diameter significantly. Nanofibrous structures with diameters of the order of 150 nm can be produced by the addition of about 10 vol.‐% DMF to the solvent (chloroform). DMF additions also yield a narrow, unimodal distribution of fibers, compared to the bimodal distribution typically detected in electrospun polymers.

Jet breakdown without (left) and with DMF addition to the solution.     

静电纺丝工艺参数对PMMA／富勒烯纤维形貌的影响

采用甲苯与二甲基甲酰胺（DMF）混合溶液做溶剂,以静电纺丝法制备了含有富勒烯（C60）的聚甲基丙烯酸甲酯（PMMA）纤维,利用扫描电镜观察了纤维的形貌,分析了PMMA的质量分数、溶剂比、纺丝电压、收集距离等对纤维形貌及平均直径的影响。结果表明：PMMA溶液的浓度以及溶剂比对纤维的形貌起着主导作用,当二者变化时,纤维结构变化较大。纤维的平均直径随着PMMA浓废、纺丝电压的增大而增大;当甲苯/DMF体积比增大时,纤维平均直径先增大后减小;纤维形貌受收集距离的影响较小。