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Construction of coal pitch-based HA-K grafted poly condensates and their excellent anti-temperature and viscosity-reducing properties

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Petroleum Science 2024年第4期21卷 2806-2816页

作者： Jing Tan Wei Zhang Xiu-Ling yan Hao Zhou Sher Bahadar Khan Seitkhan Azat shi-You yan Hao-Jie Ma Xin-Tai Su Xinjiang Key Laboratory of Clean Conversion and High Value Utilization of Biomass Resources College of Chemistry and Chemical Engineering Yili Normal University School of Environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling South China University of Technology Drilling Fluid Branch of CNPC Xibu Drilling Engineering Company Limited Department of Chemistry Faculty of Science King Abdulaziz University PO Box 80203 Faculty of Chemistry and Chemical Technology Al-Farabi Kazakh National University Urumchi Huatailong Chemical Additives Co. Ltd.

Humic acids(HAs) are widely used as filtrate and viscosity reducers in drilling fluids. However, their practical utility is limited due to poor stability in salt resistance and high-temperature resistance. Hightemperature coal pitch(CP) is a by-product from coal pyrolysis above 650.C. The substance's molecular structure is characterized by a dense arrangement of aromatic hydrocarbon and alkyl substituents. This unique structure gives it unique chemical properties and excellent drilling performance, surpassing traditional humic acids in drilling operations. Potassium humate is prepared from CP(CP-HA-K) by thermal catalysis. A new type of high-quality humic acid temperature-resistant viscosity-reducer(Graft CP-HA-K polymer) is synthesized with CP-HA-K, hydrolyzed polyacrylonitrile sodium salt(Na-HPAN),urea, formaldehyde, phenol and acrylamide(AAM) as raw materials. The experimental results demonstrate that the most favorable conditions for the catalytic preparation of CP-HA-K are 1 wt% catalyst dosage, 30 wt% KOH dosage, a reaction temperature of 250.C, and a reaction time of 2 h, resulting in a maximum yield of CP-HA-K of 39.58%. The temperature resistance of the Graft CP-HA-K polymer is measured to be 177.39.C, which is 55.39.C higher than that of commercial HA-K. This is due to the abundant presence of amide, hydroxyl, and amine functional groups in the Graft CP-HA-K polymer,which increase the length of the carbon chains, enhance the electrostatic repulsion on the surface of solid particles. After being aged to 120.C for a specified duration, the Graft CP-HA-K polymer demonstrates significantly higher viscosity reduction(42.12%) compared to commercial HA-K(C-HA-K). Furthermore,the Graft CP-HA-K polymer can tolerate a high salt concentration of 8000 mg.L-1, measured after the addition of optimum amount of 3 wt% Graft CP-HA-K polymer. The action mechanism of Graft CP-HA-K polymer on high-temperature drilling fluid is that the Graft CP-HA-K polymer can increase the re

关键词： Viscosity breaker Heat resistance Base mud Graft CP-HA-K polymer CP Salt resistance

Large eddy simulation study of 3D wind field in a complex mountainous area under different boundary conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 541-556页

作者： yan LI Lei yan Xuhui HE School of Civil Engineering Central South UniversityChangsha410075China National Engineering Research Center for High-speed Railway Construction Changsha410075China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structures Changsha410075China

Large eddy simulations generally are used to predict 3D wind field characteristics in complex mountainous *** simulation boundary conditions,such as the height and length of the computational domain or the characteristics of inflow turbulence,can significantly impact the quality of *** this study,we examined these boundary conditions within the context of the mountainous terrain around a long-span cable-stayed bridge using a wind tunnel *** sizes of computational domains and turbulent incoming wind velocities were used in large eddy *** results show that when the height of the computational domain is five times greater than the height of the terrain model,there is minimal influence from the top wall on the wind field characteristics in this complex mountainous *** the length of the wake region of the computational domain has negligible effects on the wind *** in the inlet boundary reduces the length of the wake region on a leeward hill with a low slope,but has less impact on the mean wind velocity of steep hills.

关键词： Large eddy simulation(LES) Spectral representation method Recycling method High mountainous canyon Wind characteristics Atmospheric boundary layer Computational domain

Difference in microstructural characteristics of stamp-charged coke and gravity-charged coke with approximate macroscopic performance

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Journal of Iron and Steel Research International 2024年第5期31卷 1050-1062页

作者： Chong Zou Zheng-yan Huang Jian-yun Li Bin Li shi-wei Liu Yuan She School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710311ShaanxiChina Technical Center of Shandong Iron and Steel Co. Ltd.(Laiwu Branch)Jinan271104ShandongChina

The microstructural characteristics including optical texture,porosity and pore structure and chemical structure of stamp-charged coke(SCC)and gravity-charged coke(GCC)with similar conventional macro-indicators were investigated,and the properties including micro-strength,reactivity of coke matrix and that after alkali enrichment were comparatively studied by various characterization *** anisotropic structure of SCC is composed of high content of fine mosaic texture,while the content of medium mosaic texture,coarse texture and fibrous texture is *** statistical average shows that the fine mosaic average of SCC(24.89%)is 3.78 times the GCC average(6.58%),and the coarse mosaic average(1.24%)is only about 1/3 of the GCC average(3.43%).The porosity of SCC is lower than that of GCC,but tamping process does not lead to the fact that the number of closed pores of SCC is significantly lower than that of *** the structure of SCC is compact,its pore number is large and the pore wall is *** of coke with diameter less than 150 nm seem unaffected by tamping *** aromatic structure of SCC was less ordered than that of GCC,which was speculated to be related to the addition of more low metamorphic coal in *** microscopic strength and structural strength of SCC are lower than those of *** reactivity of coke matrix is affected by the specific surface area,but it is not the determining factor of its *** improvement in dissolution reactivity of coke after potassium enrichment is independent of coke type.

关键词： Stamp-charged coke Optical texture Porosity Microstructure Reactivity

The influence of yttrium and manganese additions on the degradation and biocompatibility of magnesium-zinc-based alloys:In vitro and in vivo studies

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Journal of Magnesium and Alloys 2024年第2期12卷 608-624页

作者： Lei shi yang yan Chun-sheng Shao Kun Yu Bo Zhang Liang-jian Chen Third Xiangya Hospital Central South UniversityChangsha 410013China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China Department of Mechanical Engineering City University of Hong KongHong KongChina

The repair and regeneration of bone defects are highly challenging orthopedic ***,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human *** aim of our study is to develop a magnesium alloy with a controllable degradation that can closely match bone tissue to help injuries heal in vivo and avoid cytotoxicity caused by a sudden increase in ion *** this study,we prepared and modified Mg-3Zn,Mg-3Zn-1Y,and Mg-2Zn-1Mn by hot extrusion,and used Mg-2.5Y-2.5Nd was as a *** then investigated the effect of additions of Y and Mn on alloys'*** results show that Mn and Y can improve not only compression strength but also corrosion *** alloy Mg-2Zn-1Mn demonstrated good cytocompatibility in vitro,and for this reason we selected it for implantation in *** degraded Mg-2Zn-1Mn implanted a bone defect area did not cause obvious rejection and inflammatory reaction,and the degradation products left no signs of damage to the heart,liver,kidney,or ***,we find that Mg-2Zn-1Mn can promote an osteoinductive response in vivo and the formation of bone regeneration.

关键词： Magnesium alloy Biodegradation Biocompatibility Bone regeneration Bone defect repair

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Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： yan Qi Xin Zhang Jun Li Dong-liang Zhao shi-hai Guo yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

Application of carbon materials for Zn anode protection in aqueous Zn metal batteries

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Rare Metals 2024年第10期43卷 4807-4843页

作者： Cui-Qin Chao yan-Nan Li yan Zhao College of Energy Materials and Chemistry Inner Mongolia University School of Physical Science and Technology Inner Mongolia University

Aqueous Zn metal batteries (AZMBs) have gained widespread attention due to their high theoretica specific capacity,good safety,and low *** Zn anodes suffer from serious problems of dendrites and side reactions,which should be solved by modifying the Zn anode (Zn host,protective layer),electrolyte,and *** materials with structurally tunable and physicochemical stability properties have been widely used in the study of Zn anode protection and have also been reviewed in the past ***,review reports on carbon-based Zn anodes for Zn anode protection from new perspectives are still urgently ***,the timeliness of the review reports is very valuable for researchers to timely and accurately understand the dynamics of the research ***,this review firs reports the significance of AZMBs and summarizes the current main challenges that should be solved for practical ***,the ways to construct long-life Zn anodes using carbon materials from the perspectives of modified carbon materials with gradient properties (gradient zincophilicity,gradient electrical conductivity,and multigradient deposition) as protective layers/hosts to guide Zn ions toward bottom-up gradient Zn deposition are *** addition,the recent advances of carbon materials for electrolyte and separator modifications are ***,the remaining challenges and future perspectives of carbon materials in AZMBs Zn anode protection are briefly outlined.

关键词： Anode protection Aqueous Zn battery Carbon Gradient deposition

Low-Carbon Dispatch of an Integrated Energy System Considering Confidence Intervals for Renewable Energy Generation

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Energy Engineering 2024年第2期121卷 461-482页

作者： yan shi Wenjie Li Gongbo Fan Luxi Zhang Fengjiu yang Power Supply Service Supervision and Support Center East Inner Mongolia Electric Power Co.Ltd.Tongliao028000China School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing102206China

Addressing the insufficiency in down-regulation leeway within integrated energy systems stemming from the erratic and volatile nature of wind and solar renewable energy generation,this study focuses on formulating a coordinated strategy involving the carbon capture unit of the integrated energy system and the resources on the load storage side.A scheduling model is devised that takes into account the confidence interval associated with renewable energy generation,with the overarching goal of optimizing the system for low-carbon *** begin with,an in-depth analysis is conducted on the temporal energy-shifting attributes and the low-carbon modulation mechanisms exhibited by the source-side carbon capture power plant within the context of integrated and adaptable operational *** from this analysis,a model is devised to represent the adjustable resources on the charge-storage side,predicated on the principles of electro-thermal coupling within the energy ***,the dissimilarities in the confidence intervals of renewable energy generation are considered,leading to the proposition of a flexible upper threshold for the confidence *** on this,a low-carbon dispatch model is established for the integrated energy system,factoring in the margin allowed by the adjustable *** the final phase,a simulation is performed on a regional electric heating integrated energy *** simulation seeks to assess the impact of source-load-storage coordination on the system’s low-carbon operation across various scenarios of reduction margin *** findings underscore that the proactive scheduling model incorporating confidence interval considerations for reduction margin reserves effectively mitigates the uncertainties tied to renewable energy *** harmonized orchestration of source,load,and storage elements,it expands the utilization scope for renewable energy,safeguards the economic efficiency of system operati

关键词： Integrated energy system carbon capture power plant confidence interval optimized scheduling

MLH1 promoter germline-methylation in selected probands of Chinese hereditary non-polyposis colorectal cancer families

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World Journal of Gastroenterology 2008年第48期14卷 7329-7334页

作者： Heng-Hua Zhou shi-yan yan Xiao-yan Zhou Xiang Du Tai-Ming Zhang Xu Cai Yong-Ming Lu San-Jun Cai Da-Ren shi Department of Pathology Cancer Hospital/Institute Fudan University Department of Oncology Shanghai Medical College Fudan University Shanghai 209032 China Department of Gastroenterology Xinhua Hospital Shanghai Jiaotong University School of Medicine Shanghai 200092 China Department of Abdominal Surgery Cancer Hospital/Institute Fudan University Shanghai 200032 China

AIM： To detect the MLH1 gene promoter germline- methylation in probands of Chinese hereditary non- polyposis colorectal cancer （HNPCC）, and to evaluate the role of methylation in MLH1 gene promoter and molecular genetics in screening for ***： The promoter germline methylation of MLH1 gene was detected by methylation-specific PCR （MSP） in 18 probands from unrelated HNPCC families with high microsatellite-instability （MSI-H） phenotype but without germline mutations in MSH2, MLH1 and MSH6 genes. At the same time, 6 kindreds were col- lected with microsatellite-stability （MSS） phenotype but without germline mutations in MSH2, MIH1 and MSH6 genes as controls. The results of MSP were confirmed by clone sequencing. To ensure the reliability of the results, family H65 with nonsense germline mutation at c.2228C 〉 A in MSH2 gene was used as the negative control and the cell line sw48 was used as the known positive control along with water as the blank control. Immunochemical staining of MIH1 protein was performed with Envision two-step method in those patients with aberrant methylation to judge whether the status of MLH1 gene methylation affects the expression of MLH1 ***： Five probands with MIH1 gene promoter methylation were detected in 18 Chinese HNPCC families with MSI-H phenotype but without germline mutations in MSH2, MLH1 and MSH6 genes. Two of the five probands from families H10 and H29 displayed exhaustive-methylation, fulfilling the Japanese criteria （JC） and the Amsterdam criteria （AC）, respectively. The other 3 probands presented part-methylation fulfilling the AC. Of the 13 probands with unmethylation phenotype, 8 fulfilled the JC and the Bethesda guidelines （BG）, 5 fulfilled the AC. The rate of aberrant methylation in MLH1 gene in the AC group （22.2%, 4/18） was higher than that in the JC/BG groups （5.6%, 1/18） in all HNPCC families with MSI-H phenotype but without germline mutations in PISH2, PIIH1 and MSH6 genes. However, no proband with m

关键词： Hereditary non-polyposis colorectal cancer MLH1 Methylation Germline Methylation-specific PCR Microsatellite phenotype

Modeling human gastric cancers in immunocompetent mice

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Cancer Biology & Medicine 2024年第7期21卷 553-570页

作者： Weihong Zhang shilong Wang Hui Zhang yan Meng shi Jiao Liwei An Zhaocai Zhou Department of Stomatology Department of Medical UltrasoundShanghai Tenth People's HospitalTongji University Cancer CenterTongji University School of MedicineShanghai 200072China State Key Laboratory of Genetic Engineering School of Life SciencesZhongshan HospitalFudan UniversityShanghai 200032China Collaborative Innovation Center for Cancer Personalized Medicine School of Public HealthNanjing Medical UniversityNanjing 211166China

Gastric cancer(GC)is a major cause of cancer-related mortality *** is determined by multiple(epi)genetic and environmental factors;can occur at distinct anatomic positions of the stomach;and displays high heterogeneity,with different cellular origins and diverse histological and molecular *** heterogeneity has hindered efforts to fully understand the pathology of GC and develop efficient *** the past decade,great progress has been made in the study of GC,particularly in molecular subtyping,investigation of the immune microenvironment,and defining the evolutionary path and *** mouse models,particularly immunocompetent models that mimic the cellular and molecular features of human GC,in combination with organoid culture and clinical studies,have provided powerful tools for elucidating the molecular and cellular mechanisms underlying GC pathology and immune evasion,and the development of novel therapeutic ***,we first briefly introduce current progress and challenges in GC study and subsequently summarize immunocompetent GC mouse models,emphasizing the potential application of genetically engineered mouse models in antitumor immunity and immunotherapy studies.

关键词： Gastric cancer heterogeneity mouse model GEMM immunocompetent

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