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Dual-Functional Organotelluride Additive for Highly Efficient Sulfur Redox Kinetics and Lithium Regulation in Lithium–Sulfur Batteries 被引量:2
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作者 Wei Zhang Fenfen Ma +5 位作者 Qiang Wu Ziqi Zeng Wei Zhong Shijie Cheng Xin Chen Jia Xie 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期126-133,共8页
High energy density and low cost made lithium–sulfur(Li–S)batteries appealing for the next-generation energy storage devices.However,their commercial viability is seriously challenged by serious polysulfide shuttle ... High energy density and low cost made lithium–sulfur(Li–S)batteries appealing for the next-generation energy storage devices.However,their commercial viability is seriously challenged by serious polysulfide shuttle effect,sluggish sulfur kinetics,and uncontrollable dendritic Li growth.Herein,a dual-functional electrolyte additive,diphenyl ditelluride(DPDTe)is reported for Li–S battery.For sulfur cathodes,DPDTe works as a redox mediator to accelerate redox kinetics of sulfur,in which Te radical-mediated catalytic cycle at the solid–liquid interface contributes significantly to the whole process.For lithium anodes,DPDTe can react with lithium metal to form a smooth and stable organic–inorganic hybrid solid-electrolyte interphase(SEI),enabling homogeneous lithium deposition for suppressing dendrite growth.Consequently,the Li–S battery with DPDTe exhibits remarkable cycling stability and superb rate capability,with a high capacity up to 1227.3 mAh g^(-1)and stable cycling over 300 cycles.Moreover,a Li–S pouch cell with DPDTe is evaluated as the proof of concept.This work demonstrates that organotelluride compounds can be used as functional electrolyte additives and offers new insights and opportunities for practical Li–S batteries. 展开更多
关键词 electrolyte additive Li anode Li2 s deposition Li–s battery sulfur kinetics
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Polymethylmethacrylate bone cements and additives: A review of the literature 被引量:11
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作者 Manit Arora Edward KS Chan +1 位作者 Sunil Gupta Ashish D Diwan 《World Journal of Orthopedics》 2013年第2期67-74,共8页
Polymethylmethacrylate(PMMA) bone cement technology has progressed from industrial Plexiglass administration in the 1950 s to the recent advent of nanoparticle additives. Additives have been trialed to address problem... Polymethylmethacrylate(PMMA) bone cement technology has progressed from industrial Plexiglass administration in the 1950 s to the recent advent of nanoparticle additives. Additives have been trialed to address problems with modern bone cements such as the loosening of prosthesis, high post-operative infection rates, and inflammatory reduction in interface integrity. This review aims to assess current additives used in PMMA bone cements and offer an insight regarding future directions for this biomaterial. Low index(< 15%) vitamin E and low index(< 5 g) antibiotic impregnated additives significantly address infection and inflammatory problems, with only modest reductions in mechanical strength. Chitosan(15% w/w PMMA) and silver(1% w/w PMMA) nanoparticles have strong antibacterial activity with no significant reduction in mechanical strength. Future work on PMMA bone cements should focus on trialing combinations of these additives as this may enhance favourable properties. 展开更多
关键词 POLYMETHYLMETHACRYLATE Bone cement cement nanoparticle Vitamin E additive ARTHROPLAsTY Artificial joint fixation POsT-OPERATIVE infection Mechanical WEAKNEss Fat additive Antibiotics
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Formulation Design of the Multi-component Cement Additive by Using Engineering Statistics 被引量:1
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作者 黄弘 沈晓冬 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第3期538-544,共7页
A novel methodology for the formulation design of the multi-component cement additive for the low early strength blend cement was presented by using engineering statistics.Components of cement additive such as trietha... A novel methodology for the formulation design of the multi-component cement additive for the low early strength blend cement was presented by using engineering statistics.Components of cement additive such as triethanolamine,chloride,saccharide and a kind of divalent alcohol were simultaneously tested according to the arrangement of response surface methodology.Mathematical models were established to express the quantitative relationship between the chemical components of cement additive and the compressive strength of treated blend cement.The effectiveness and the possible interactions of these four chemicals contributing to the strength development of blend cement were further explored by the pareto chart and the contour plot.Finally according the performance analysis of four chemicals,the optimized formulations were brought forward and were validated in practical trials by Turkey's multiple comparison. 展开更多
关键词 cement additive blend cement EFFECTIVENEss INTERACTION engineering statistics
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Optimization of cement-based grouts using chemical additives 被引量:8
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作者 Mohammad Reza Azadi Ali Taghichian Ali Taheri 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第4期623-637,共15页
Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after excavation.There are many methods of grouting.Permeation grouting is one of the most common types... Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after excavation.There are many methods of grouting.Permeation grouting is one of the most common types in which the grout material is injected to the pore spaces of the ground.In grouting operations,the grout quality is important to achieve the best results.There are four main characteristics for a grout mixture including bleeding,setting time,strength,and viscosity.In this paper,we try to build some efficient grouting mixtures with different water to cement ratios considering these characteristics.The ingredients of grout mixtures built in this study are cement,water,bentonite,and some chemical additives such as sodium silicate,sodium carbonate,and triethanolamine(TEA).The grout mixtures are prepared for both of the sealing and strengthening purposes for a structural project.Effect of each abovementioned ingredient is profoundly investigated.Since each ingredient may have positive or negative aspect,an optimization of appropriate amount of each ingredient is determined.The optimization is based on 200 grout mixture samples with different percentages of ingredients.Finally,some of these grout mixtures are chosen for the introduced project.It should be mentioned that grouting operations depend on various factors such as pressure of injection,ground structure and grain size of soils.However,quality of a grout can be helpful to make an injection easier and reasonable.For example,during the injection,a wrong estimated setting time can destroy the injected grout by washing the grout or setting early which prevents grouting.This paper tries to show some tests in easy way to achieve a desirable sample of grout. 展开更多
关键词 Permeation grouting BLEEDING setting time Chemical additives cement-based grout
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Assessment of the Performances of Carboxylic Acid Monomers as Fluid Loss Additives for Oil-Well Cement
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作者 Hexing Liu Yi Huang +3 位作者 Jinlong Zheng Ye Tian Mengran Xu Huajie Liu 《Fluid Dynamics & Materials Processing》 EI 2022年第4期999-1013,共15页
The application of polycarboxylic acid as a fluid loss additive for cement(i.e.,a substance specifically designed to lower the volume of filtrate that passes through the cement)can prolong the thickening time of cemen... The application of polycarboxylic acid as a fluid loss additive for cement(i.e.,a substance specifically designed to lower the volume of filtrate that passes through the cement)can prolong the thickening time of cement slurries.Given the lack of data about the effects of carboxylic acid monomers as possible components for the additives traditionally used for oil-well cement,in this study different cases are experimentally investigated considering different types of these substances,concentrations,temperatures,and magnesium ion contamination.The results demonstrate that itaconic acid has a strong retarding side effect,while maleic and acrylic acids have similar influences on the thickening time of the cement slurry.The rheological properties of the cement slurry tend to deteriorate when the carboxylic acid monomer content in the fluid loss additive is increased to 40%.If the temperature exceeds 80°C,there is a significant decrease in the related impact on the thickening duration.With an increase in the intrusion of magnesium ions to>0.5%,both the rheological properties of the cement slurry and the thickening time are affected in a negative way. 展开更多
关键词 Fluid-loss control additive cement slurry carboxylic acid monomer thickening performance
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ZnFe-LDHs型固井水泥H_(2)S防腐剂制备及性能评价
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作者 何敏会 姚明 +2 位作者 闫宇博 梅开元 程小伟 《钻井液与完井液》 CAS 北大核心 2024年第3期364-373,共10页
我国高酸性油气田资源丰富,但在开发过程中固井水泥石将长期受到H_(2)S等酸性介质的侵蚀,严重威胁到油气井的施工和安全生产。针对此问题,采用水热共沉淀法制备了ZnFe-LDHs型H_(2)S防腐剂,并将掺有优选出的ZnFe-LDHs的水泥石置于5%浓度... 我国高酸性油气田资源丰富,但在开发过程中固井水泥石将长期受到H_(2)S等酸性介质的侵蚀,严重威胁到油气井的施工和安全生产。针对此问题,采用水热共沉淀法制备了ZnFe-LDHs型H_(2)S防腐剂,并将掺有优选出的ZnFe-LDHs的水泥石置于5%浓度的Na_(2)S溶液中分别在常温及60℃下浸泡1、3、7、14、28 d,通过抗压强度测试、XRD、SEM等表征手段,分析ZnFe-LDHs对水泥石的防H_(2)S腐蚀能力和作用机理。结果表明,晶化温度为90℃下制备的Zn/Fe物质的量的比为(1~4)∶1的ZnFe-LDHs性能较好,均可提高水泥石的抗压强度,且强度随着Zn/Fe物质的量的比增加而增大,即掺加了Zn/Fe物质的量的比为4∶1的ZnFe-LDHs水泥石的作用效果最为明显,其强度增长了10.11%,而经Na2S溶液浸泡后,其早期强度降低,浸泡7 d时其强度相比于浸泡前在常温及60℃下分别增长了8.73%、4.96%,7 d后强度基本趋于稳定,这是由于ZnFe-LDHs能促进水化反应,并在浸泡后期与Na2S反应生成ZnS,提高水泥石的致密性,从而有效防止H_(2)S对水泥石的腐蚀。 展开更多
关键词 ZnFe-LDHs 固井水泥 防腐剂 H_(2)s
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Influence of Additives on the Solvothermal Synthesis in the Formation of Zn-MOF_5 被引量:1
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作者 LIN Xiaoying SU Ting +4 位作者 ZHONG Qinhua SHI Ronghui LIUMinyi LIU Yamin LU Dongfei 《Journal of Donghua University(English Edition)》 EI CAS 2018年第6期491-494,共4页
The influences of additives of NH_3,HCl,KOH and CH_3OH on the solvothermal synthesis of the Zn-based metal-organic frameworks(Zn-MOF_5s)were investigated.Powder X-ray diffraction(PXRD),thermal gravimetric analysis(TGA... The influences of additives of NH_3,HCl,KOH and CH_3OH on the solvothermal synthesis of the Zn-based metal-organic frameworks(Zn-MOF_5s)were investigated.Powder X-ray diffraction(PXRD),thermal gravimetric analysis(TGA),Fourier translation infrared spectroscope(FT-IR),N_2adsorption/desorption at 77 K and CO_2sorption measurements were used to characterize the as-prepared Zn-MOF_5s.The experimental results showthat additives of NH_3,CH_3OH,HCl and KOH in the synthesis of the Zn-MOF_5s do not change the underlying topology,but they are extremely sensitive to the pore textural properties,thus changing the CO_2adsorption capacity.Additives would lower the pore width and the surface area,and then lower the CO_2adsorption capacity of Zn-MOF_5s. 展开更多
关键词 Zn-MOF5s additives INFLUENCE CO2 adsorption capacity nanocrystal
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纳米C-S-H的合成及其对普通硅酸盐水泥早期水化的影响
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作者 赵双 张丽敏 +1 位作者 王新程 房延凤 《混凝土》 CAS 北大核心 2024年第8期102-105,共4页
为提高水泥基材料的早期强度,制备了纳米C-S-H悬浮液,并通过XRD和Zeta电位对其组成和粒度分布、稳定性进行了分析。通过水化放热、热重分析和扫描电子显微镜扫描电镜(SEM)研究了纳米C-S-H对硅酸盐水泥早期强度发展、水化放热、水化产物... 为提高水泥基材料的早期强度,制备了纳米C-S-H悬浮液,并通过XRD和Zeta电位对其组成和粒度分布、稳定性进行了分析。通过水化放热、热重分析和扫描电子显微镜扫描电镜(SEM)研究了纳米C-S-H对硅酸盐水泥早期强度发展、水化放热、水化产物的影响。结果表明:合成了具有半结晶结构的稳定的纳米C-S-H悬浮液。纳米C-S-H的加入促进了C3S的水化,尤其是在前24 h,并使水泥的水化诱导期明显缩短。含有0.05%纳米C-S-H砂浆的8 h、16 h和24 h抗压强度分别提高了176.0%、145.6%和43.9%,与此同时,砂浆的3 d抗压强度没有明显减少。 展开更多
关键词 纳米C-s-H 水泥 水化 早强 微观形貌
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基于潮汐附加构造应力的2013年灯塔M_(S)5.1地震射出长波辐射变化分析
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作者 荆涛 Boonphor Phetphouthongdy +4 位作者 Chansouk Sioudom 刘洋洋 李继庚 康春丽 马未宇 《地震》 CSCD 北大核心 2024年第2期52-62,共11页
针对2013年1月23日辽宁灯塔M_(S)5.1地震,利用引潮力附加构造应力(Additional Tectonic Stress Caused By Tidal Force,ATSCTF)计算模型,计算得到震中位置(41.5°N,123.2°E)在地震前5周以及震后3周(2012年12月16日—2013年2月1... 针对2013年1月23日辽宁灯塔M_(S)5.1地震,利用引潮力附加构造应力(Additional Tectonic Stress Caused By Tidal Force,ATSCTF)计算模型,计算得到震中位置(41.5°N,123.2°E)在地震前5周以及震后3周(2012年12月16日—2013年2月15日)的ATSCTF变化。地震发生时,ATSCTF垂直方向分量处于高相位点附近,显示引潮力对本次正断层走滑型地震具有诱发作用。以ATSCTF变化周期的各低相位点时间(2012年12月19日、2013年1月4日、2013年1月18日、2013年2月2日)数据分别为背景,各周期期后数据分别与背景逐日相减,计算研究区(36°N~46°N,118°E~128°E)范围内,National Oceanic and Atmospheric Administration(NOAA)卫星射出长波辐射数据(Outgoing Long Wave Radiation,OLR)在各ATSCTF周期时段分布及其变化。结果显示,无震的ATSCTF变化的A、B、D周期,震中附近OLR无变化;发震的ATSCTF变化的C周期,在空间上,该地区震前OLR仅震中及其南侧区域发生了显著连续升高变化过程,在时间上经历了初始微异常→异常加强→高峰→衰减→发震→平静的演化过程,与岩石应力加载—破裂经历:初始微动破裂→扩张破裂→应力闭锁→地震爆发→平静的力学演化过程中各阶段红外辐射特征一致;显示引潮力对处于临界状态的活动断层具有诱发作用,而OLR是地震构造应力应变过程辐射表征。 展开更多
关键词 2013年灯塔M_(s)5.1地震 长波辐射 潮汐附加构造应力 震前ATsCTF周期异常
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Solutionizing of Additional Ions in Belite-rich Clinkers and the Properties of the Resulting Cement
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作者 王政 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第5期834-837,共4页
Belite-rich cement (BRC) can be made at lower temperature, but it has unsatisfactory reactivity. The crystal structure of dicalcium silicate (C2S) was modified by solutionizing some additional irons. By adding bar... Belite-rich cement (BRC) can be made at lower temperature, but it has unsatisfactory reactivity. The crystal structure of dicalcium silicate (C2S) was modified by solutionizing some additional irons. By adding barium sulfate (BaSO4) in the raw meals, the clinkers were easier to be burnt, and the compressive strength of BaSO4-modified BRC was considerably improved. The distortion of the crystal structure of C2S was confirmed by the interplanar distance change and nuclear magnetic resonance (NMR) of ^29Si in C2S. An effective way was found to activate C2S and to broaden the application field of Belite-rich cement. 展开更多
关键词 belite cement solid solubility additional ions crystal structure
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Chloro-propylene Sulfite as Electrolyte Additive for Li/S Batteries
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作者 Guo Xiang XU Qi LU Lei WEN Ping HE 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期557-560,共4页
Chloro-propylene sulfite (CIPS) was employed as electrolyte additive of Li/S batteries for the first time. Linear potential sweep test showed that the CIPS keeps high electrochemical stability even under the voltage... Chloro-propylene sulfite (CIPS) was employed as electrolyte additive of Li/S batteries for the first time. Linear potential sweep test showed that the CIPS keeps high electrochemical stability even under the voltage of 5.0V. Being used as electrolyte additive in Li/S batteries, CIPS displayed an excellent property for self-discharge prohibition. With CIPS additive the Li/S cells initial discharge capacity was 856.2 mAh·g^-1 and 830.8 mAh·g^-1 at the current density of 15 mA.g and 30 mA·g^-1 , after 30 cycles the discharge capacities were contained at as high as 753.8 mAh.g and 715.6 mAh·g^-1. By means of infrared spectra, TG/DTA experiment and element conten analysis the speculated reason of CIPS's novel function as additive was proposed. 展开更多
关键词 Chloro-propylene sulfite Li/s battery additive sELF-DIsCHARGE capacity cycle.
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Effect of Water Addition on Rheological Behaviour of BauxiteBased Low-cement Castables
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作者 ZHOUXianxin MichelRIGANU ZHOUNingsheng 《China's Refractories》 CAS 2004年第3期25-34,共10页
Water addition has direct impact on castables and needs to be under control placement and properties, In this work, two rheological properties, flow resistance and torque viscosity, have been measured against time, wi... Water addition has direct impact on castables and needs to be under control placement and properties, In this work, two rheological properties, flow resistance and torque viscosity, have been measured against time, with different water addition in the same bauxile-based LC Castable mix. The flow resistance indicates the mobility, whereas the torque viscosity dictates the stability of a castable during installation. It has been observed that with 6.0wt% water addition, such a mix possesses good vibration castable characteristics; with 6.5 wt%, it shows good self-flow castable characteristics; and with 7.0 wt%, it can be a good pumpable castable, in every case with comparable mechanical properties. While with 7.5 wt% water addition, the properties of such castable are definitively impaired. 展开更多
关键词 RHEOLOGY Flow resistance Torque viscosity Water addition Low cement castable
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Absolute Stability of Nonlinear Systems with Two Additive Time-varying Delay Components 被引量:3
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作者 Bassem Ben Hamed Mohamed Chaabane Walid Kacem 《International Journal of Automation and computing》 EI 2011年第4期391-402,共12页
In this paper, we present a new sufficient condition for absolute stability of Lure system with two additive time-varying delay components. This criterion is expressed as a set of linear matrix inequalities (LMIs), ... In this paper, we present a new sufficient condition for absolute stability of Lure system with two additive time-varying delay components. This criterion is expressed as a set of linear matrix inequalities (LMIs), which can be readily tested by using standard numerical software. We use this new criterion to stabilize a class of nonlinear time-delay systems. Some numerical examples are given to illustrate the applicability of the results using standard numerical software. 展开更多
关键词 Time-varying delay system additive delay absolute stability linear matrix inequalities (LMIs s-PROCEDURE Lyapunov Krasovskii functional stabilization.
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Effects of Ultrafine Comminution on the Dissolution of Active Ingredients from Compound Feed Additive of Strobilanthes cusia
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作者 CHEN Yi-long LI Shi-jie +1 位作者 ZHENG Shao-yan ZHANG Dan-yan 《Animal Husbandry and Feed Science》 CAS 2012年第5期201-203,240,共4页
[Objective] The research aimed to explore the effects of comminution technology on the dissolution of active components from compound feed additive of Strobi/anthes cusia. [Method] Using active component adenosine in ... [Objective] The research aimed to explore the effects of comminution technology on the dissolution of active components from compound feed additive of Strobi/anthes cusia. [Method] Using active component adenosine in principal herb S. cusia and chlorogenic acid in minister drug Lonicera japonica Thunb. as dissolution indices,the effects of ultrafine comminution on the dissolution degree of compound feed additive of S. cusia were analyzed. [ Result] The dissolution degree of adenosine and chlorogenic acid in ultra micro particles were obviously higher than that of common particles. Ultrafine comminution could significantly quicken the dissolution rate of adenosine and chlorogenic acid in compound feed additive of S. cusia, shorten the extraction time, avoid the breakage of active components in long-time extraction process,and meanwhile saved the energy greatly. [ Conclusion] The ultrafine comminution technology could obviously increase the dissolution degree of active components in compound feed additive of S. cusia. 展开更多
关键词 Ultrafine comminution Compound feed additive of s. cusia Dissolution degree China
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The Construction of Pairwise Additive Minimal BIB Designs with Asymptotic Results
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作者 Kazuki Matsubara Sanpei Kageyama 《Applied Mathematics》 2014年第14期2130-2136,共7页
An asymptotic existence of balanced incomplete block (BIB) designs and pairwise balanced designs (PBD) has been discussed in [1]-[3]. On the other hand, the existence of additive BIB designs and pairwise additive BIB ... An asymptotic existence of balanced incomplete block (BIB) designs and pairwise balanced designs (PBD) has been discussed in [1]-[3]. On the other hand, the existence of additive BIB designs and pairwise additive BIB designs with k = 2?and?λ = 1?has been discussed with direct and recursive constructions in [4]-[8]. In this paper, an asymptotic existence of pairwise additive BIB designs is proved by use of Wilson’s theorem on PBD, and?also for some l?and k the exact existence of l?pairwise additive BIB designs with block size k and?λ = 1?is discussed. 展开更多
关键词 Incidence Matrix Pairwise BALANCED DEsIGN (PBD) BALANCED Incomplete Block DEsIGN (BIBD) additive BIB DEsIGN Pairwise additive BIB DEsIGN Wilson’s Theorem
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The Project “Development and Application of FCC Additive for Maximization of Propylene and Isobutylene” Passed SINOPEC's Appraisal
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《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第1期70-70,共1页
The research project'Development and application of FCC additive for maximization of propylene and isobutylene'jointly undertaken by RIPP,the Baling Petrochemical Company(BPC)and the SINOPEC
关键词 FCC Development and Application of FCC additive for Maximization of Propylene and Isobutylene Passed sINOPEC’s Appraisal The Project
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Mechanical Properties, Metallurgical Characteristics and Anisotropy of Additive Manufacturing of 316L
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作者 D. Moreno Y. Nahmana +4 位作者 O. Nafman O. Kam B. Wolfman A. Y. Cohen M. Shapira 《Journal of Minerals and Materials Characterization and Engineering》 2022年第2期209-223,共15页
Additive manufacturing (AM), while enabling the production of parts with complex geometries, presents new challenges. In particular, the achievement of the basic mechanical properties of the alloy must be ensured. In ... Additive manufacturing (AM), while enabling the production of parts with complex geometries, presents new challenges. In particular, the achievement of the basic mechanical properties of the alloy must be ensured. In general, the strength-ductility properties of metals depend strongly on their microstructure, and controlling these properties requires paying attention to the alloy composition, processing technique and heat treatments. Austenite 316L stainless steel parts produced by AM demonstrate good ductility and high yield strength—higher than that obtained with annealed 316L. Some preferred orientation of the mechanical properties was found as a function of the laser path, namely, the Young’s modulus varied with respect to the angle between the build direction and the normal to the build direction. In the present study, samples of AM 316L in three orientations relative to the print direction (0&#730;, 45&#730;and 90&#730;) are compared to a forged sample. Mechanical properties, scanning electron microscopy-SEM fractography, energy dispersive X-ray spectroscope-EDS analysis of the fracture and optical cross section images of the samples along the stress tension after the failure are presented. 展开更多
关键词 ss316L additive Manufacturing (AM) Preferred Orientation Mechanical Properties Young’s Modulus
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C-S-H-PCE对基准水泥体系水化的影响
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作者 陈星国 《福建建设科技》 2024年第4期78-83,共6页
传统的早强剂在实际应用过程中会对混凝土的早强性能和耐久性能产生一定的影响,因此开发新型早强剂尤为重要。其中新开发的纳米C-S-H-PCE新型早强剂能够更好地加速水泥基材料的早期水化,有利于水化产物的快速生成。探究C-S-H-PCE早强剂... 传统的早强剂在实际应用过程中会对混凝土的早强性能和耐久性能产生一定的影响,因此开发新型早强剂尤为重要。其中新开发的纳米C-S-H-PCE新型早强剂能够更好地加速水泥基材料的早期水化,有利于水化产物的快速生成。探究C-S-H-PCE早强剂对基准水泥体系水化的影响,对C-S-H-PCE的研发和应用具有重要意义。本文基于水泥水化的溶解-沉淀理论,研究C-S-H-PCE对基准水泥体系水化各阶段的影响,通过水化热测试对比分析C-S-H-PCE、纳米SiO_(2)对水化历程的影响,并测定各阶段的凝结时间和抗压强度。结果表明,C-S-H-PCE的加入显著缩短水化诱导期、提高水化最大放热速率、促进未水化颗粒的溶解;C-S-H-PCE缩短了初凝和终凝时间,1d和3d的强度得到明显提升。由此可知C-S-H-PCE对基准水泥水化的作用规律和影响机制,从而建立了水化微结构和宏观力学性能之间的联系。 展开更多
关键词 C-s-H-PCE早强剂 基准水泥体系 水化热 凝结时间 抗压强度 纳米siO_(2)
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表面接枝C—S—H的岩沥青对高温油井水泥石力学性能的影响 被引量:1
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作者 王佳 张春梅 +2 位作者 张晔 程小伟 梅开元 《钻井液与完井液》 CAS 北大核心 2023年第6期806-814,共9页
研究了表面接枝C—S—H的岩沥青对高温油井水泥石力学性能和微观结构的影响,采用压力试验机及XRD、TG、SEM和EDS对油井水泥石的力学性能和微观结构进行了测试和表征。研究结果表明,与纯水泥石相比,掺入1%未改性岩沥青的水泥石3 d抗压强... 研究了表面接枝C—S—H的岩沥青对高温油井水泥石力学性能和微观结构的影响,采用压力试验机及XRD、TG、SEM和EDS对油井水泥石的力学性能和微观结构进行了测试和表征。研究结果表明,与纯水泥石相比,掺入1%未改性岩沥青的水泥石3 d抗压强度下降了2.98%,而掺入1%表面接枝C—S—H岩沥青的水泥石3 d抗压强度提高了4.26%。物相分析和热重实验表明,表面接枝C—S—H岩沥青的加入不会引起水化产物类型的变化,而掺量为3%表面接枝C—S—H的岩沥青水泥石养护3 d的失重量比纯水泥石高1.01%,说明表面接枝C—S—H的岩沥青可以促进水泥的水化。水泥石的微观形貌和元素分析表明,未改性岩沥青在180℃下热解导致沥青颗粒破碎,而接枝C—S—H的岩沥青表面形成的富Si层可以避免沥青颗粒因气孔而引起破碎,使得未改性岩沥青水泥石界面处的C元素含量较接枝C—S—H的岩沥青水泥石高29.14%,未改性岩沥青水泥石基体中C元素含量较接枝C—S—H的岩沥青水泥石高13.76%。 展开更多
关键词 岩沥青 C—s—H晶种 化学接枝 油井水泥 高温固井
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Cement Resources, Agrominerals, Construction, Marble, Dimension and Decor Stone Resources, Gemstone and Jewelry Resources of Pakistan 被引量:4
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作者 Muhammad Sadiq Malkani 《Open Journal of Geology》 2020年第8期900-942,共43页
Large deposits of cement raw material and resources like limestone, gypsum and shales/clays found from the Koh Sulaiman area of South Punjab (Saraikistan) and Balochistan Provinces, Pakistan. The installation of cemen... Large deposits of cement raw material and resources like limestone, gypsum and shales/clays found from the Koh Sulaiman area of South Punjab (Saraikistan) and Balochistan Provinces, Pakistan. The installation of cement industries especially in South Punjab/Saraikistan Province due to close occurrences of resources should develop the area and increase the export. The Koh Sulaiman regions of South Punjab (Saraikistan) have huge gypsum deposits which deserve for further exploitation. Pakistan is agricultural country and fertility of cultivated lands is vital. Fertilizer resources like phosphate deposits are moderate but the deposits of phosphate and potash bearing rocks are very vast and need their further explorations and exploitation in the Indus Basin. Pakistan has very large construction, dimension and decor stone deposits like limestone, marble, dolomite and igneous rocks like granite, dolerite, serpentine, etc. which needs further exploitation for the development of the areas and increase export. Pakistan is spending a lot of earnings for importing glass, glass wares, pottery, clay, etc. while Pakistan has these resources which needs exploitation of own resources. The best structures and geotectonic elements like the Northern and Western Indus Sutures and Karakoram Suture and Indus placers which are rich in gemstones and jewelry resources. To increase gems and jewelry export, these industries requires reduction in gemstones smuggling and encouragement for gem appraisal and jewelry industry at high level for value addition. In short, Pakistan is rich in natural resources but poor in development. Try should be made to develop and export the own mineral commodities like cement, gypsum, marble, gemstones and jewelry. 展开更多
关键词 cement Resources Agrominerals CONsTRUCTION MARBLE Dimension and Decorstone Resources Gems and Jewelry Resources Export Value addition Pakistan
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