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二硫代磷酸盐对天然橡胶的硫化促进作用

合成橡胶工业 1990年第S1期13卷 200-207页

作者： Byron H.To 马维德 monsanto Chemical company USA

以前的工作表明,O,O-二丁基二硫代磷酸锌在天然橡胶中与苯并噻唑类促进剂并用时,可获得优异的抗返原性。然而,这样的促进剂组合的焦烧安全性很小。加入N-环己基硫代邻苯二甲酰亚胺,可以改善焦烧安全性。这是由于二丁基二硫代磷酸锌被... 详细信息

以前的工作表明,O,O-二丁基二硫代磷酸锌在天然橡胶中与苯并噻唑类促进剂并用时,可获得优异的抗返原性。然而,这样的促进剂组合的焦烧安全性很小。加入N-环己基硫代邻苯二甲酰亚胺,可以改善焦烧安全性。这是由于二丁基二硫代磷酸锌被转化成O,O-二丁基三硫代过二磷酸环己酯(不对称二硫化物),后者是一种不焦烧共促进剂,并赋予胶料优良的抗返原性。分析研究表明,二丁基二硫代磷酸(或其盐)在橡胶加工过程中充当自动催化的促进剂,与2-巯基苯并噻唑相似。这两类促进剂的组合,在增加交联速度上有叠加作用。基于这一概念,二硫代磷酸盐类促进剂体系的系统开发已经开始,以研究这些体系对各种功能性能的影响。本论文介绍了用统计学方法设计试验的结果,并且认为二硫代磷酸盐促进剂与半有效硫化体系相似。

关键词：促进剂二硫代磷酸盐天然橡胶焦烧安全性半有效硫化体系返原性疲劳性能促进作用焦烧时间二硫化物

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改善硫化测试

合成橡胶工业 1990年第S1期13卷 248-254页

作者： P.J.DiMauro J.A.Sezna H.A.Pawkowski 曹振纲 monsanto Chemical company USA

在将来,减小胶料偏差将成为橡胶厂改进产品质量、满足用户需要、避免损失时间及不合格材料的关键因素,橡胶厂减小胶料偏差的能力取决于材料偏差和测试试验。借助于下面推荐的测试仪器,硫化仪测试数据的偏差能明显减小。改进测量硫化的... 详细信息

在将来,减小胶料偏差将成为橡胶厂改进产品质量、满足用户需要、避免损失时间及不合格材料的关键因素,橡胶厂减小胶料偏差的能力取决于材料偏差和测试试验。借助于下面推荐的测试仪器,硫化仪测试数据的偏差能明显减小。改进测量硫化的数据有助于减小数据偏差,但进一步的改善则要求重新设计仪器。ODR 2000和NDR 2000型硫化仪由于改进设计能提高仪器的性能水平。2000型系列硫化仪对操作者影响不敏感。附加了很多新的功能以便提高试验效率并维持硫化仪最佳性能。随着更多重复测试数据的出现,硫化仪测试能在更高要求的未来世界继续服务于橡胶加工过程。

关键词：硫化仪温度恢复时间硫化时间连接器转子测试结果模腔最大转矩测试温度硫化曲线

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热塑性弹性体的光明未来

合成橡胶工业 1990年第S1期13卷 7-15页

作者： Charles P.Rader 胡炳镛 monsanto Chemical company USA

引言目前橡胶工业中正在发生一种重要的全球性变化。尽管这种变化还局限于橡胶工业的非轮胎方面,但是,它的重要性也许能和半世纪以前合成橡胶出现以来的任何事件相媲美。

关键词：热塑性弹性体热塑性塑料注射成型橡胶制品橡胶挤出机橡胶工业热固橡胶加工三元乙丙橡胶弹性体合金

迟延硫化作用的共活化作用——Ⅰ.促进剂-硫磺硫化体系的聚合型非迁移性硫化共活化剂

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合成橡胶工业 1990年第S1期13卷 15-21页

作者： A.Y.Coran L.H.Davis 杨俊平 monsanto Chemical company USA USA

本工作的一个目的是开发迟延作用促进剂-硫磺硫化体系的共活化剂。这类助剂是要使交联键形成的速度增加,而几乎不改变混炼胶的抗焦烧性能及其硫化胶的性能。本工作的另一个目的是使所提供的硫化体系的共活化剂,除具有迟延活化作用外,不... 详细信息

本工作的一个目的是开发迟延作用促进剂-硫磺硫化体系的共活化剂。这类助剂是要使交联键形成的速度增加,而几乎不改变混炼胶的抗焦烧性能及其硫化胶的性能。本工作的另一个目的是使所提供的硫化体系的共活化剂,除具有迟延活化作用外,不会从复合橡胶制品(如轮胎)的一个部位迁移或扩散到另一个部分。本工作的开始部分是评价一些高分子量的乙烯基吡啶-二烯烃乳液共聚物作为乳聚丁苯橡胶(SBR)硫化的共活化剂的行为。这些共聚物中的大部分在室温下是类橡胶物质,它容易与SBR共混。使用乙烯基吡啶共聚物的早期结果是令人鼓舞的。

关键词：共活化剂硫磺硫化体系促进剂丁二烯共聚物中乙烯基抗焦烧性能活化作用硫化特性硫化作用硫化速度

Bifunctional erdite rods as an effective flocculant and catalyst in electro-Fenton systems

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Progress in Natural Science:Materials International 2023年第4期33卷 518-525页

作者： Tong Sun Chengzhong Sun Ying Wang Jiancong Liu Htet Oo Kaung Suiyi Zhu Zhongkai University of Agriculture and Engineering Crude Oil Shipping and Marketing company Dagang Oilfield Company CNPC Supervision company Jilin Oilfield Company CNPC School of Environment Northeast Normal University Lversheng Environmental Technology company

Erdite rods were massively produced via a one-step alkaline heating route with the complete recycling of waste waterwork sludge. The sludge was a mixture of Fe, Mn, Al, and Si, but only Fe-bearing substances were converted as erdite rods. The erdite rods had 100 nm diameter and 1-5 μm length, and was hydrolysed as Fe-SH-rich flocs in wastewater. Its hydrolysis became slow in the presence of electric field but accelerated by adding PMS. pNitrophenol was targeted as organic pollutant to determine the rods performance. The removal efficiency of pnitrophenol was 7.4% by adding erdite rods, but up to 44.6% with the addition of erdite/PMS, and then dramatically increased to 98.7% in the electro-PMS/erdite system. Given that the free Fe was less than 30 mg/L,the surface Fe of Fe-SH-rich flocs predominated the PMS activation, in which the surface Fe enriched in electronic field and then was involved in the redox reaction of PMS and then reduced by the adjacent S on flocs. This enabled the recycling of Fe3+/Fe2+to activate PMS at high level. Thus, the erdite rods showed high p-nitrophenol removal efficiency in the electro-Fenton system in comparison with the other reported reagents, e.g. ferrous sulphate,ferbam, pyrite and FeS.

关键词： Erdite rods p-Nitrophenol Fenton reaction Wastewater treatment Flocculant

Systemic RNAi in western corn rootworm, Diabrotica virgifera virgifera, does not involve transitive pathways

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Insect Science 2018年第1期25卷 45-56页

作者： Huarong Li Andrew J. Bowling Premchand Gandra Murugesan Rangasamy Heather E. Pence Robert E. McEwan Chitvan Khajuria Blair D. Siegfried Kenneth E. Narva Dow AgroSciences LLC 9330 Zionsville Rd. Indianapolis Indiana USA Department of Entomology University of Nebraska Lincoln Nebraska USA monsanto company Chesterfield Missouri USA Entomology and Nematology Department University of Florida Gainesville Florida USA

Western corn rootworm （WCR, Diabrotica virgifera virgifera LeConte） is highly sensitive to orally delivered double-stranded RNA （dsRNA）. RNAi in WCR is systemic and spreads throughout the insect body. This raises the question whether transitive RNAi is a mechanism that functions in WCR to amplify the RNAi response via production of secondary siRNA. Secondary siRNA production is achieved through RNA-dependent RNA polymerase （RdRP） activity in other eukaryotic organisms, but RdRP has not been identified in WCR and any other insects. This study visualized the spread of the RNAi- mediated knockdown of Dr v-ATPase C mRNA throughout the WCR gut and other tissues using high-sensitivity branched DNA in situ hybridization. Furthermore, we did not detect either secondary siRNA production or transitive RNAi in WCR through siRNA sequence profile analysis. Nucleotide mismatched sequences introduced into either the sense or antisense strand of v-ATPase C dsRNAs were maintained in siRNAs derived from WCR fed with the mismatched dsRNAs in a strand specific manner. The distribution of all siRNAs was restricted to within the original target sequence regions, which may indicate the lack of new dsRNA synthesis leading to production of secondary siRNA. Thus, the systemic spread of RNAi in WCR may be derived from the original dsRNA molecules taken up from the gut lumen. These results indicate that the initial dsRNA dose is important for a lethal systemic RNAi response in WCR and have implications in developing effective dsRNA traits to control WCR and in resistance management to prolong the durability of RNAi trait technology.

关键词： corn rootworm Diabrotica secondary siRNA production systemic RNAi transitive RNAi

The Technology and Economic Analysis of the DCC and MIP Processes at Anqing Petrochemical company

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China Petroleum Processing & Petrochemical Technology 2006年第3期8卷 7-13页

作者： Li Jibing SINOPEC Anqing Branch company Anqing 246001

In order to meet the demand for gasoline quality upgrading, SINOPEC Anqing Branch Com- pany has retrofitted the DCC unit with the MGD technology and equipped the FCC unit with the MIP technology. This article makes an analysis and comparison on commercial application of the MIP and the DCC/MGD processes in terms of technology and economics while focusing on their specific features and methods for maximization of their economic benefits.

关键词： MIP DCC/MGD process economics economic benefit

Recent Advances in Nutrient Sensing and Signaling

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Molecular Plant 2012年第6期5卷 1170-1172页

作者： Daniel P.Schachtman monsanto company CC4N700 Chesterfield Pkwy WestChesterfieldMO 63017USA

Nutrient sensing and signaling is an important area of plant biological research because of the role of plant nutrition in crop production and the constraints that nutrient limita- tions put on plant growth and optimal yields. The increasing cost, the limited supplies, and the negative impacts of excess application of fertilizer on the environment have all led to more research into understanding how plants acquire, sense, and utilize nutrients. Approximately two and a half years ago, Molecular Plant published a special issue （March 2010） with a series of review articles and ori- ginal research papers on nutrient sensing and signaling. Many reviews have appeared and provide excellent sum- maries for research advances in this area （Ho and Tsay, 2010; Krouk et al., 2010a; Chiou and Lin, 2011; Gutierrez, 2012）. This highlight updates readers on some of the advances and emerging themes in this field of research since the special issue.

关键词：成本及成本分析理解力内皮缩血管肽类前体细胞淋巴母细胞白血病淋巴瘤设备和供应胰岛素植物综述

Conversion of carbon dioxide to valuable petrochemicals:An approach to clean development mechanism

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Journal of Natural Gas Chemistry 2011年第3期20卷 219-231页

作者： Farnaz Tahriri Zangeneh Saeed Sahebdelfar Maryam Takht Ravanchi Catalyst Research Group Petrochemical Research and Technology Company (NPC-RT) National Petrochemical Company

The increase of atmospheric carbon dioxide and the global warming due to its greenhouse effect resulted in worldwide concerns. On the other hand, carbon dioxide might be considered as a valuable and renewable carbon source. One approach to reduce carbon dioxide emissions could be its capture and recycle via transformation into chemicals using the technologies in C1 chemistry. Despite its great interest, there are difficulties in CO2 separation on the one hand, and thermodynamic stability of carbon dioxide molecule rendering its chemical activity low on the other hand. Carbon dioxide has been already used in petrochemical industries for production of limited chemicals such as urea. The utilization of carbon dioxide does not necessarily involve development of new processes, and in certain processes such as methanol synthesis and methane steam reforming, addition of CO2 into the feed results in its utilization and increases carbon efficiency. In other cases, modifications in catalyst and/or processes, or even new catalysts and processes, are necessary. In either case, catalysis plays a crucial role in carbon dioxide conversion and effective catalysts are required for commercial realization of the related processes. Technologies for CO2 utilization are emerging after many years of research and development efforts.

关键词： carbon dioxide utilization C1 chemistry clean development mechanism catalysis greenhouse effects