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Chinese Chemical Letters 2006年第6期17卷 817-820页

作者： Jing Ping WANG jian ru ma Jing Yang NIU School of Chemistry and Chemical Engineering Henan University Kaifeng 475001

An unprecedented 1D zigzag chain alkaline earth metal derivative, {[Ba（DMF）3 （H20）2][Ba（DMF）412（P2W18O62）}n, （DMF=N, N-dimethyl formamide） containing Dawson hetero- polyanion has been successfully synthesized and characterized by X-ray crystallography. Two barium cations bridged by three DMF ligands in parallel combination with the Dawson-type heteropolyanion [P2W18O62]^6- and then the resulting subunits {[Ba（DMF）4]2（P2WlsO62）}^2＋ are alternately linked together via another [Ba（DMF）3（H2O）2]^2＋ ions, constructing a 1D zigzag chain architecture.

关键词： Polyoxometalate crystal structure Dawson structure.

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Optimizations for High Performance Network Virtualization

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Journal of Computer Science & Technology 2016年第1期31卷 107-116页

作者： Fan-Fu Zhou ru-Hui ma jian Li Li-Xia Chen Wei-Dong Qiu Hai-Bing Guan Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai 200240 China

The increasing requirements of intensive interoperaterbility among the distributed nodes desiderate the high performance network connections, owing to the substantial growth of cloud computing and datacenters. Network I/O virtualization aggregates the network resource and separates it into manageable parts for particular servers or devices, which provides effective consolidation and elastic management with high agility, flexibility and scalability as well as reduced cost and cabling. However, both network I/O virtualization aggregation and the increasing network speed incur higher traffic density, which generates a heavy system stress for I/O data moving and I/O event processing. Consequently, many researchers have dedicated to enhancing the system performance and alleviating the system overhead for high performance networking virtualizatiou. This paper first elaborates the mainstreaming I/O virtualization methodologies, including device emulation, split-driver model and hardware assisted model. Then, the paper discusses and compares their specific advantages in addition to performance bottlenecks in practical utilities. This paper mainly focuses on the comprehensive survey of state- of-the-art approaches for performance optimizations and improvements as well as the portability management for network I/O virtualization. The approaches include various novel data delivery schemes, overhead mitigations for interrupt processing and adequate resource allocations for dynamic network states. Finally, we highlight the diversity of I/O virtualization besides the performance improvements in network virtualization infrastructure.

关键词： network virtualization single root I/O virtualization (SR-IOV) virtual machine monitor (VMM)

The Preparation of Unsymmetrical Diaminodimethylsilanes and the Cleavage of Silicon-Nitrogen Bonds by Acid Chloride

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Chinese Chemical Letters 1997年第11期8卷 945-946页

作者： Guo Bin RONG ru jian ma Chong Ying ZHOU Zhu Liang JIN Wan Nian WU Qing WANG (Department of Chemistry, East China University of Science and Technology, Shanghai, 200237) Department of Chemistry E. China Univ. of Sci./Technology Shanghai 200237 China

Seven unsymmetrical diaminodimethylsilanes were prepared. The reactions of these silylamine with benzoyl chloride indicated that in comparison with electronic, the steric effect played more important role on the reactivity of Si-N bond. As a new method, unsymmetrical diamide can produced by the reaction of the title compounds with diacid chloride.

关键词： Si The Preparation of Unsymmetrical Diaminodimethylsilanes and the Cleavage of Silicon-Nitrogen Bonds by Acid Chloride

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Tuning Surface Molecular Design of Porous Carbon for Blue Energy Harvesting

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Research 2024年第1期2023卷 651-662页

作者： jian Yu Zhong-Lin Wang Tianwei ma Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life ***,because of limited performance,existing systems do not lend themselves to practical *** it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive ***,we show that manipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the *** findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how manipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

Enhanced properties of stone coal-based composite phase change materials for thermal energy storage

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International Journal of Minerals,Metallurgy and materials 2024年第1期31卷 206-215页

作者： Baoshan Xie Huan ma Chuanchang Li jian Chen Key Laboratory of Renewable Energy Electric-Technology of Hunan Province School of Energy and Power EngineeringChangsha University of Science and TechnologyChangsha 410114China State Key Laboratory of Disaster Prevention and Reduction for Power Grid Changsha University of Science and TechnologyChangsha 410114China

Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building *** coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite *** prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an *** combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading *** showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface *** loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% *** data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed *** obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical *** SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.

关键词： thermal energy storage phase change material stone coal vanadium extraction secondary utilization

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magnetocaloric effect and phase transition critical behavior of La0.75Sr0.25Mn0.9Co0.1O3 compound synthesized under the high pressure

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Tungsten 2024年第3期6卷 621-632页

作者： Jing Zhao Lei Gao jian-Jun Zhao Wei Wei Hui-Qin Yun ru Xing Huai-Jin ma Xiang Jin Luo-Meng Chao School of Physical Science and Technology Key Laboratory of Magnetism and Magnetic Materials for Higher Education in Inner Mongolia Autonomous Region Baotou Teachers' College National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths School of Physics and Electronic Information Inner Mongolia Normal University College of Science Inner Mongolia University of Science and Technology

In this study,a novel method is proposed for producing perovskite rare-earth manganese oxide magnetic refrigeration materials that exhibit superior properties compared to similar *** maximum magnetic entropy change values for this sample are 1.44 and 3.75 J·kg-1·K-1for magnetic fields of 2 and 7 T,***,its relative cooling power has been calculated to be 101.96 and 404.78 J·kg-1,indicating good *** results were obtained using the sample synthesized under a pressure of 4 GPa,and the sample has undergone a second phase *** critical behavior of the sample fits well with the mean field *** different magnetic fields,there is a significant overlap between the values of the maximum magnetic entropy change and the temperature-averaged entropy change,indicating that the refrigeration performance of the sample after high pressure can approach its maximum capability.

关键词： High-pressure synthesis magnetocaloric effect Relative cooling power magnetic phase transition

MicroED as a powerful technique for the structure determination of complex porous materials

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Chinese Journal of Structural Chemistry 2024年第3期43卷 41-54页

作者： Chao ma Cong Lin jian Li State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic UniversityKowloonHong Kong China

Porous materials have garnered significant attention in recent *** the intrinsic relationship between their structures and properties requires precise knowledge of their atomic ***-crystal X-ray diffraction(SCXRD)has traditionally been the primary method for elucidating such structures,but it demands large,high-quality crystals,often exceeding 5μm in *** growth of these crystals can be a time-consuming process,especially for one-and two-dimensional *** explore structures at the nanoscale,MicroED(microcrystal electron diffraction(ED))offers unprecedented insights into the realm of *** revolutionary technique enables researchers to uncover intricate details within nanoscale structures,promising to reshape our fundamental understanding of *** this review,we delve into the applications of MicroED in the study of various porous materials,including zeolites,metal-organic frameworks(MOFs),and covalent organic frameworks(COFs).We emphasize the pivotal role of MicroED in nanomaterial characterization,enabling precise crystallographic analysis and phase identification.

关键词： Atomic structure MicroED Porous materials Three-dimensional electron diffraction

magnesium-containing pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel Research International 2024年第7期31卷 1623-1635页

作者： Li-ming ma jian-liang Zhang Yao-zu Wang Xiao-yong ma Gui-lin Wang Zhuo Li Hui-qing jiang Zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group Co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag

Comprehensive tensile properties improved by deep cryogenic treatment prior to aging in friction-stir-welded 2198 Al–Li alloy

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Rare Metals 2024年第10期43卷 5403-5409页

作者： jian-Qiu Sun Yue ma Chong Gao Hong-Yun Luo School of materials Science and Engineering Beihang University Chinalco Research Institute of Science and Technology

In order to improve the comprehensive mechanical properties,deep cryogenic treatment （DCT）prior to aging was carried out on friction-stir-welded（FSW） 2198 Al-Li alloy;afterward,the microstructure and tensile properties were characterized by means of optical microscopy （OM）,transmission electron microscopy（TEM） and tensile *** results show that FSW 2198 alloy through DCT prior to aging （DAT） possesses superior tensile properties than conventional aging treatment （AT）The microstructural analysis reveals that DAT alloy exhibits a finer grain structure,since DCT might effectively alleviate the residual stress in FSW 2198 alloy and thus decrease the driving force for grain coarsening in subsequent aging ***,DCT generates dislocation multiplication,which provides more preferential nucleation sites for T1 （Al2CuLi） phase during subsequent aging treatment,resulting in high-density fine T1 phases and thin precipitate-free zone within DAT *** reasonable microstructure leads to DAT alloy possessing better strength-ductility combination compared to AT alloy.

关键词： Al–Li alloy Deep cryogenic treatment Friction stir welding Tensile properties

Novel process for facile preparation of mesoporous silica-based materials with controllable pore structure from coal fly ash Author links open overlay panel

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Particuology 2024年第8期91卷 128-137页

作者： jian-ming Gao Zhen Li Shujia ma Yuanyuan Zhang Fangqin Cheng Institute of Resources and Environment Engineering State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste ResourcesShanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related WastesShanxi UniversityTaiyuan 030006China

Extraction of silica from fly ash to produce mesoporous silica materials is one of the most important utilization *** silica could not be synthesized on a large-scale by conventional sol-gel *** this paper,facile preparation of mesoporous silica with controllable pore structure from fly ash by the template-free process via two steps of mineral phase transformation and selective acid etching was *** influence of crystalline structure and acid etching degree on structure of as-synthesized mesoporous silica materials was revealed,as well as mechanism of crystalline structure transformation and pore structure *** results show that mullite and quartz could be transformed into acid-soluble kaliophilite when fly ash reacted with K_(2)CO_(3)at temperature of 800-1100℃.The hexagonal kaliophilite would be transformed into orthorhombic KAlSiO_(4)-O1 phase when the temperature is controlled at 1100℃.Mesoporous silica with specific surface area of 475.93 m^(2)/g and 642.57 m^(2)/g could be synthesized from activated fly ash with kaliophilite and KAlSiO_(4)-O1 phase crystalline *** controlling the degree of acid etching,mesoporous silica materials with different pore structures can be *** paper provides a cost-effective and large-scale process for the preparation of mesoporous silica materials with controllable pore structure from solid waste fly ash.

关键词： Fly ash Mesoporous silica Crystal transformation Acid etching Controllable pore structure