民营企业也能办大事—访天津四友精细化学品有限公司总经理孙兰波

一个不足300人的民营企业,不要国家一分投资,依靠科技,凝聚人心,经过艰苦拼搏,完成科研院所未能完成的国家"九五"重点科技攻关项目,其间的辛酸苦辣,您知道吗?     

中国石油获国家职业技能等级认定资质

<正>1月23日,随着国家人力资源和社会保障部国家职业技能等级认定工作评审专家组组长宣布"中国石油天然气集团有限公司完成国家职业技能等级认定工作备案,大庆油田有限责任公司完成黑龙江省备案",标志着中国石油成为全国第一家开展国家职业技能等级认定的中央企业。"这意味着集团公司职业技能等级证书与国家职业资格证书享有同等效力,操作员工可由此享受到更多的国     

欧洲精细化工组织封杀不符合GMP标准原料的进口

目前，欧盟成员国正在将原料药GMPQ7指南转换成为本国的法律，已有大约一半的国家完成了这一转换过程，另有7个国家即将完成，还有7个国家仍然处在采纳的初期阶段。[第一段]     

饶平根:特种陶瓷发展依然任重道远

谈到特种陶瓷,华南理工大学材料学院的饶平根教授绝对是一个够资格的专业人士。他自1988年参加工作起就一直从事高性能陶瓷及超细粉体等方面的研究和开发工作,作为主要成员先后参与并完成了国家重大攻关项目、国家863项目、国家基金及省部级项目共20余项,并主持完成了多个省级科技项目     

中国石化获4项国家科技奖

<正>2018年度国家科学技术奖励大会1月8日在人民大会堂举行,中国石化有4项成果获奖。其中,中国石化销售华南公司田中山等完成的油气管道系统完整性关键技术与工业化应用成果获得国家技术发明二等奖;中国石化石油工程技术研究院、国际石油勘探开发有限公司等完成的高酸性活跃厚沥青层复杂碳酸盐岩油田钻完井技术及应用成果,扬子石化等完成的特种表面冲击强化抗应力腐蚀与疲劳技     

浙大5项成果获国家科技奖

2014年度国家科学技术奖1月9日揭晓,在北京人民大会堂举行的国家科学技术奖励大会上,浙江大学教授周雪平、吴朝晖、陈国邦、严建华、陈江华作为项目的第一完成人代表获奖单位领奖。2014年度,浙江大学作为第一完成单位完成的5个成果获得表彰,其中自然科学奖二等奖一项,技术发明奖二     

加快缔置法硫酸钾生产 摆脱依赖进口局面

沈阳化工综合利用研究所开发出问歇缔置法制取硫酸钾技术受到了国家的重视。该所与化工部科学技术研究总院合作,完成了由国家     

浙江摘得30项国家科技奖

2011年度国家科技奖励大会近日在北京举行,浙江捧回30项国家科技奖,超过2010年的19项。其中,我省为第一单位完成的有10项,包括国家技术发明二等奖2项．国家科技进步二等奖8项。     

我省上半年化工生产情况

在中央经济上实行进一步调整,政治上实现进一步安定的方针指引下,我省化工战线广大职工,积极努力,克服了种种困难,生产任务完成得较好。据统计:全省化工总产值上半年实际完成35800.19万元,完成年计划的54.24％,其中,省直企业完成15078.12万元,完成年计划的56.9％,地、市企业完成为20722.02万元,完成年计划的52.46％。国家考核的15种主要化工产品产量,达到时间过半,完成任务过半的有硫铁矿、硫酸、     

中国分离机械行业科技新成果与新产品

一、科技成果1.吉化集团公司机械厂完成了石油重大攻关项目 :LW10 0 0 A- N离心机。2 .辽阳制药机械股份有限公司完成了国家重点科技 (攻关 )项目 :SD150 0三足式吊袋上卸料离心机。3.安庆船用柴油机厂成功开发了 DPF50 0大型分离机。4 .上海化工机械厂完成了国家重点科技攻关项目 :大型化工关键单元设备的子项目——优质化碱用高效过滤式离心机。5.重庆江北机械厂完成了国家技术创新项目 :卧螺式离心脱水机与污泥浓缩机一体化。二、新产品1.金华铁路机械厂开发了 L WG50 0× 12 50 - N离心机 ,并通过省级鉴定 ,获浙江省科学进步奖 ,…     

Effect of the density of the electronic states at the valence orbital of the bridge redox molecule on the dependence of the tunnel current on the overvoltage in the case of fully adiabatic electron transition

Effect of the density of the electronic states at the valence orbital of the bridge redox molecule on the dependence of the tunnel current on the overvoltage and on the width at half maximum of the current-overvoltage curve is studied. A number of the approximate expressions for the density of states, the tunnel current and the width are obtained in the fully adiabatic limit for different particular cases. It is shown that at small values of the coupling of the electronic levels of the electrodes with the valence orbital of the redox molecule and the small values of the bias voltage two regions of the reorganization Gibbs energy exist with different dependence of the width on the reorganization Gibbs energy. The results of calculations of the density of states, the tunnel current and the width are presented and used for the interpretation of the experimental data [N.G. Tao, Phys. Rev. Lett. 76 (1996) 4066, I. Visoly-Fisher, K. Daie, Y. Terazono, C. Herrero, F. Fungo, L. Otero, E. Durantini, J.J. Silber, L. Sereno, D. Gust, T.A. Moore, A.L. Moore, S.M. Lindsay, PNAS 103 (2006) 8686].     

氮气幕对瓦斯爆炸进行阻爆实验

为阻断瓦斯爆炸在管道方向上的传播，保护管道后方区域，本文采用氮气幕来进行阻爆，所设计的实验装置在爆炸发生后能自动喷出氮气。主要研究了氮气的喷气压力和喷气时刻对阻爆功能的影响。结果表明，在喷气压力为0.1MPa时，氮气幕仅起到抑制作用，爆炸火焰能穿过整个实验管道。在喷气压力为0.2MPa时，仅部分实验能够阻爆，氮气幕产生不稳定的阻爆效果。在喷气压力为0.3MPa时，阻爆位置均稳定在左喷头和右喷头之间区域，氮气幕产生稳定地阻爆效果。喷气压力超过0.4MPa后，阻爆位置稳定在右喷头附近。在较低氮气压力0.2MPa下，喷气时刻对阻爆效果产生显著影响。随着喷气时刻延迟，氮气喷出量减小，氮气幕由不稳定阻爆变为不阻爆。喷气时刻延迟到198ms后，氮气幕便丧失阻爆功能。在喷气压力超过0.3MPa后，氮气幕阻爆效果便不受喷气时刻的影响，喷气压力对能否阻爆起决定作用。     

液滴撞击微结构疏水表面的动态特性

对去离子水滴撞击不同几何尺寸显微结构方柱和方孔状疏水表面的动态特性进行了研究。结果表明：当液滴以不同速度撞击微方柱疏水表面时,液滴展现铺展和回缩过程,且随着韦伯数（We数）增大,最大铺展直径增大,并伴随卫星液滴出现,但到达最大铺展直径的时间一致;而当液滴以相同的速度（We数相同）撞击间距不同的微方柱疏水表面时,液滴的最大铺展直径随着间距的增大而减小,且铺展过程会液滴浸润状态变得不稳定,发生由Cassie向Wenzel状态的浸润转变。当微方柱间距较小时,液滴受到的黏附功越小,越易发生向Cassie状态的转变;液滴撞击微方孔疏水表面时,液滴以规则的圆环状向外铺展和回缩,最后呈现近似规则的椭球状,不会发生向Wenzel状态的浸润转变,利用建立的物理模型对前述现象进行了分析。     

Mechanical properties and drug release rate of poly(vinyl alcohol)/poly(ethylene glycol)/clay nanocomposite hydrogels: Correlation with structure and physical properties

Poly(vinyl alcohol)/poly(ethylene glycol) hydrogels containing curcumin as a drug and the various amounts of a montmorillonite nanoclay are prepared using the freezing–thawing method. Nanoclay quantity influence on the physicomechanical properties and the drug release rate of the hydrogel as well as relationship between them is investigated. X-Ray diffraction and Atomic force microscopy analysis reveal the nanoclays have an intercalation structure in the hydrogel, and the hydrogel crystallization decreases with increasing the nanoclay inclusion. From the SEM micrographs observation, it was revealed that due to the presence of the nanoclay in the hydrogel, its porosity decreased. The naonoclay has an amount-depended dual effect on the hydrogel swelling. The swelling mechanism is a normal Fickian diffusion for all the hydrogel samples. Strong physical interactions between the nanoclays and the polymer chains in the nanocomposite hydrogels are evidenced by the rheological studies. These interactions lead to significant reinforcement of the hydrogel tensile strength, intensified by the nanoclay amount. Interestingly, the nanoclays show the capability of accelerating and, also, decelerating the drug release of the hydrogel. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47843.     

基于流热固耦合的熔盐泵转子动力特性分析

用ANSYS软件模拟了熔盐泵转子的应力与变形,研究了不同介质流量下非定常流动对转子部件的影响,考察了泵转子结构的模态性能. 结果表明,转子温度自叶轮部件沿泵轴向轴承逐渐降低,不同介质流量下叶轮内的最大等效应力均出现在叶片进口边与前盖板的结合处,泵轴与轴承的配合处出现了明显的应力集中,转子部件的最大变形出现在叶轮边缘,且最大等效应力和变形量均随介质流量增大而减小,设计流量下转子部件最大等效应力和总变形量的变化幅度最小,添加预应力后转子部件前6阶固有频率增加,但振幅变化不大,流量对转子部件模态性能的影响较小.     

A new method for the reconstruction of the particle radius distribution function from the sedimentation curve

A new method for the reconstruction of the particle radius distribution function from the sedimentation curve is proposed. This method permits us to obtain a continuous smooth distribution function. Two approaches are compared. The first approach is based on the calculation of the second derivative from the sedimentation curve. The second one is based on the solution of the original integral equation which describes a sedimentation process. Both of these approaches can be reduced to the problem of the solution of the Fredholm integral equation of the first kind. From the theory of integral equations, it is known that this problem is ill-posed. The usual methods lead to unstable solutions and we are forced to use special regularizing algorithms. In this paper, the Tikhonov regularization method is used to stabilize the solution of the integral equation. It is shown that the accuracy of both methods is higher than the accuracy of the graphical method, but the approach based on the solution of the original integral equation gives a more stable solution than that based on the derivative. The accuracy of the new method permits us to reconstruct the fine structure of the particle radius distribution function. Such an analysis cannot be carried out with the rough bar diagram obtained from the graphical method. The new method is absolutely indispensable in technology for controlling the degree of powder fineness.     

A rotating two-phase gas/liquid flow regime for pressure reduction in underwater plasma arc welding

Plasma arc welding processes are used in the off-shore industry for construction and maintenance of underwater structures and pipelines in a wet environment. At greater water depths the density of the plasma gas increases because of the greater hydrostatic pressure. This causes conductive heat losses to the wet environment to increase. To maintain the energy flux to the workpiece to be welded, the plasma arc has to burn in a local dry area with an inside pressure of 1 bar. This requirement can be fulfilled by a rotating cylinder with a liquid film flowing down the inner wall. The flow around the rotating cylinder is experimentally investigated. The rotating cylinder is placed above the work surface which is simulated by a flat plate. Because of the centrifugal forces of the rotating flow inside the gap between the lower end of the cylinder and the flat plate the water is forced out of the cylinder. The velocity distribution in the flow is measured by laser Doppler anemometry. The phase distribution in the two-phase flow in the gap is measured by local electrical probes. The static pressure inside the gaseous atmosphere is reduced in comparison to the hydrostatic pressure of the surrounding water. The pressure reduction is given by the void fraction, the phase distribution and the volume flow rates of both phases in the gap as well as by the speed of revolution and the design of the cylinder and the work surface. The influence of these parameters on heat transfer from the workpiece to the two-phase flow regime is also investigated.     

微通道内火焰传播的研究进展

微燃烧器与阻火器淬火单元均为可燃气体燃烧的微通道,目前对微燃烧器的研究较充分,而对阻火器淬火单元的研究较少. 本工作概述了影响火焰在微通道内传播的因素,指出对各因素的研究还需深入,有利于澄清争议;简述了火焰在微通道内传播的数学模型的研究进展,提出微通道内流体流动流型的判定亟需完善;确定在高速爆轰条件下,阻火器内的流动为湍流;推荐将雷诺应力湍流模型与层流有限速率模型结合进行阻火器内高速爆轰火焰传播的数值模拟,推荐采用以密度为基础的算法进行求解;指出了微通道内火焰传播研究的成果与不足,展望了其发展方向.     

Effects of extrusion process,type and content of clays,and foaming process on the clay exfoliation in HMS PP composites

The use of a high melt strength polypropylene (HMS PP) matrix reinforced with layered clays could be very useful to improve the properties of materials produced with processes involving melt stretching, like foaming. The control of the particles structure, that is, the degree of exfoliation and the clay distribution in the polymeric matrix, is the key to achieve the desired properties. In this study, the effects of the extrusion process, the clay type and content, and the foaming process on the morphology of different HMS PP based composites are studied. Both, natural and organomodified clays were used. The extrusion process has a negative effect in the composites containing natural clays as their interlayer distance decreases as the number of extrusion cycles increases. On the contrary, this process improves the intercalation of the organomodified clays. However, in both composites the interlayer spacing decreases when the clay content increases. While a percolated network is formed in the composites containing organomodified clays, no network is formed with the natural clays. Finally, the effect of the foaming process has also been analyzed. The Improved Compression Moulding (ICM) route was used to produce the foamed materials. This technique subjects the materials only to a temperature and a pressure gradient without applying any other external forces that could contribute to the clay exfoliation. In this way, only the effects of foaming and melt stretching are observed. In both composites, an increase in the interlayer distance is observed when the materials are foamed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42828.     

受压容器开口补强的优化设计

将有限元应力分析方法与设计方法相结合 ,提出了基于受压容器口补强的极限分析理论和优化设计思想 ,采用有限元前处理程序 ,自动生成常见球罐和柱罐的优化力学模型 ,并在屏幕上或用汇图仪绘制出罐体的三维图形。建立起受压容器开口补强优化设计的教学模型。根据此问题的特殊性 ,采用改进后的 0 .6 1 8法进行优化计算 ,优化过程中将模型划分成可变域和不可变域两部分 ,利用计算机的顺序文件存贮不变域单元刚度阵 ,提高了有限元重分析的计算效率