Isomerization of 4,6-Dinitrobenzofuroxan—A DFT Study

The present study concentrates on the isomerization process of 4,6-dinitrobenzofuroxan and the monoionic forms of its bicyclic isomers. The ionic forms shed some light on the stability of those isomers in an ionizing electric field or static charging. To achieve the goals of the study, certain density functional theory (DFT) calculations have been carried out at the restricted and unrestricted levels of B3LYP using 6-31G(d) and 6-311 + G(d,p) basis sets. The stabilities and some other quantum chemical properties of the isomers and the ionic forms were obtained. It was found that upon charging, the bicyclic isomers undergo ring opening of the five-membered ring to yield stable structures.     

A Study on Hydrotropy—Petroleum and Petrochemical Products

Abstract

A comprehensive investigation of the solubility and mass transfer coefficient enhancement of benzene through hydrotropy has been undertaken. The solubility and mass transfer coefficient studies were carried out using hydrotropes such as citric acid, urea, nicotinamide, and sodium salicylate under a wide range of hydrotrope concentrations (0 to 3.0 mol/L) and different system temperatures (303 to 333 K). The effectiveness of hydrotropes was measured in terms of Setschenow constant KS and reported for all hydrotropes used in this study.     

Advantages of Mild Hydrocracking FCC Feed—A Pilot Plant Study

Abstract

In view of increasingly stringent environmental regulations with respect to SOx and particulate emissions, the allowable sulphur and nitrogen levels in diesel and gasoline are reducing all over the world. Fluid catalytic cracking (FCC) unit is a major source of fuels produced from a refinery. Any attempt to reduce sulphur and nitrogen content of distillates produced from FCC unit will greatly improve the quality of fuels. In the present work, pilot plant studies were conducted to evaluate the options of hydrotreating and mild hydrocracking (MHC) of FCC feedstock. Experiments were conducted on commercially available catalyst samples using high nitrogenous vacuum gas oil (VGO) as feedstock. MAT experiments were also conducted to compare the conversions and yields of untreated, hydrotreated, and MHC VGO at constant operating conditions. Pilot plant data showed that MHC of VGO would produce additional fuels to the extent of 15% under moderate operating conditions besides improving the quality of FCC feedstock. The mild hydrocracked VGO as feed was found to increase FCC conversion by 2 wt%, increase fuels by 2.5 wt%, reduce residue by 2.8 wt% compared to untreated vacuum gas oil.     

A Study on CaSO4 Fouling Deposit

This paper reports the influences of heat transfer surface properties on the formation of CaSO4 fouling deposition during flow boiling heat transfer.The surfaces of several test heaters have been treated by surface modification techniques.such as dynamic mixing ion beam implantation and dynamic mixing magnetron sputtering to reduce surface energy.Fouling runs with these heaters were carried out at different heat fluxes,flow velocities and salt concentrations.The results show that heat transfer surfaces with low surface energy experienced significantly a reduced formation of CaSO4 deposit.     

A Study of Thin Sandstone Reservoirs by High-resolution Seismic Inversion

In recent years, with the development of the oil/gas exploration technology and with the intensive exploration of the known oil-gas bearing basins in the world, there are fewer and fewer easily explored structural oil/gas reservoirs, while more and more subtle oil/gas pools are found in the recently discovered oil/gas reservoirs. The thin sandstone reservoirs are not easily found in the initial phase of exploration, since they are affected by such factors as structural environment, stratigraphi…     

DFT Study of Geometrical and Vibrational Features of Sulfur Containing Amino Acids in Hydrated Media： L-Cysteine and L-Methionine

Geometry optimization at the B3LYP/6-31＋＋G＊ level of theory has been undertaken on clusters containing L-Met （L-methionine） or L-Cys （L-cysteine） surrounded by eight water molecules. The comparison of the structural parameters of L-Met and L-Cys with X-ray experimental values is in good agreement within 4.8%. This result shows that the privileged positions of water molecules and the possible hydrogen bonding network formed around the backbone of both AAs （amino acids） are adequate. Subsequent calculations of the harmonic vibrational modes followed by a post-processing treatment enable us to assign the vibrational modes of L-Met and L-Cys surrounded explicitly by eight water molecules. The frequencies of the assigned modes are in good agreement with available IR （infra red） and Raman values within 5%.     

Study on Modeling for a New FCC Technique——MIP Riser Reactor

This research work developed a model for the MIP riser reactor using the data collected from an industrial MIP unit.Based on analysis of flow patterns in the reactor,three models were established and a comparison was made on each other.The results indicated that Model Ⅲ,which was assumed a plug flow in the first reaction zone and a gas plug flow and a continuously stirred catalyst flow in the second reaction zone,was the best.The results of this research could offer an information and guidance for optimization and development of MIP unit.     

甲烷部分氧化机理的DFT研究—CH_4的活化与解离

使用量子化学计算方法,通过对密度泛函理论(DFT)的应用,采用周期性的分子模型(vaccumslab),模拟计算了甲烷和甲基在Ni(111)表面的吸附和解离(CH4(g)→CH3(ads)+Hads→CH2(ads)+2Hads)。甲烷、甲基和亚甲基分别吸附于Ni(111)表面的hcp、bridge和bridge位置。以物理吸附于催化剂表面的甲烷为反应物,化学吸附于催化剂表面的亚甲基和氢为产物,计算得到甲烷和甲基的解离能分别为42kJ/mol和45 5kJ/mol,活化能分别为202 2kJ/mol和98 2kJ/mol,并对解离路径进行了详细的分析。     

双酚—A国内外发展概况

1 概况 2,2—双—(4′羟苯基)丙烷或称二羟基苯丙烷,简称双酚—A(以下简称BPA)。 1923年德国库尔特·阿尔贝尔特公司开始BPA工业化生产,自40年代末环氧树脂(以下称EPX)获得应用后,BPA的发展极其迅速。早期生产厂家是法国普洛基尔和德国拜尔公司。美国道化学公司于1941年,壳牌公司     

WSC—30A油水分离器

<正> 为满足油田污水回注、污水分油等作业的需要,江汉机械研究所研制成功一种新型油水分离装置—WSC—30A油水分离器。这种装置是运用多种分离原理,通过两级分     

A—N防锈剂的应用

介绍一种具有新型分子结构的无灰型防锈添加剂在工业润滑油中的应用研究情况。研究结果表明，A－N剂可以用来调制工业用油。     

341—115A封隔器设计

３４１—１１５Ａ新型封隔器是对原有旧式封隔器基础上进行了多处结构改造研制而成,该封隔器易于制造、密封好、防渗漏,能实现多级封隔器串联使用,可用于多层分级注水作业．座封时不用水泥车,只靠注水管线的压力就可进行座封,解决了油田急需．     

RX—A—03型多用数据显示记录仪

据悉 ,输油站原用的进出站压力记录仪是一种多量程混合式记录仪 ,其内部为机械结构 ,故障频发、不能准确记录和起到保护作用、安全隐患很大。长春输油管理处采用ＲＸ Ａ 0 3型多用数据显示记录仪取代了原有的落后记录仪。ＲＸ Ａ 0 3型多用数据显示记录仪有其先进的性能和功能。其显著特点就在于采用最新电子技术与微处理器技术 ,这种显示记录仪属高品质产品 ,拥有高性能、大容量存储、多种显示方式、多种数据记录查询功能 ,可以进行通讯、无机械传动机构等特点。该显示记录仪投入使用后 ,将使输油站科学管理水平提升到一个新的阶段 ,为高效…     

A Study on continuous and intermittent THAI™ processes in Brazil's Northeastern Region

Toe-to-Heel Air Injection – THAI? is an enhanced oil recovery technique that employs in situ combustion combined with technologies for horizontal well drilling, which is unprecedented in Brazilian oilfields. Motivated by this context, this research is intended to studying the application of the THAI? process in a semisynthetic reservoir, with characteristics similar to those found in Brazil's Northeastern region. At the end, it was demonstrated that the intermittent air injection increased the oil recovery, when compared to the continuous injection, what reinforce the need for further research turned to ongoing and future projects in mature oilfields.     

FDS—4A催化剂应用分析

通过分析ＦＤＳ－４Ａ催化剂两次标定数据、掺炼加氢焦化汽油和加工高氮原料油数据,表明ＦＤＳ－４Ａ催化剂具有较高的脱硫脱氮活性,能够满足重速装置扩能改造和加工高硫高氮原料以及掺炼加氢焦化汽油的需要。     

Hydrocyclones for De-oiling Applications—A Review

Abstract

The de-oiling hydrocyclone is a device for liquid–liquid separation and production water cleanup. Significant progress has been made in the development of such a device since its first introduction and use in the late 1970s. The present article is a literature review of development and research work performed so far on de-oiling hydrocyclones. It reviews the performance parameters affecting the de-oiling hydrocyclone operation; namely, the inlet oil concentration and drop size distribution, the turn-down ratio, the pressure drop ratio, the flow split, and the geometrical parameters. The article addresses work done to elucidate the internal flow structure and performance of de-oiling hydrocylones in both experimental and computational fluid dynamics areas. Challenges and remaining research issues are also identified.