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Microstructure of ferrospheres in fly ashes: SEM, EDX and ESEM analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1595-1600页

作者： qing-feng xue sheng-gao LU Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition College of Environmental and Resource Sciences Zhejiang University Hangzhou 310027 China

Ferrospheres in fly ashes from a coal-fired power plant were extracted by a magnetic separation technique and their microstructure was studied by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and environmental scanning electron microscopy (ESEM). Ferrospheres in fly ashes show significant iron enrichment compared to their respective fly ashes. Iron oxides in ferrospheres mainly occur as minerals magnetite (Fe3O4) and hematite (α-Fe2O3), which are derived mainly from the decomposition and oxidation of iron-bearing minerals in coal during combustion. EDX data indicate that ferrospheres also contain Si, S, Al and Ca resulting from quartz, mullite, anhydrite and amorphous materials. A large percentage of ferrospheres are commonly 5～50 μm in size. The microstructure of ferrospheres includes smooth, polygonal, dendritic, granular and molten drop characteristics. SEM coupled with EDX provided fast and accurate results of the microstructure and chemical composition of ferrospheres, and helped us to assess environmental issues related to the disposal and utilization of fly ashes.

关键词： Fly ash Ferrosphere Microstructure Scanning electron microscopy (SEM)

Effect of short-time low-temperature austenitizing on microstructure and mechanical properties of DT300 ultra-high strength steel fabricated by laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第7期31卷 1763-1777页

作者： Chen-yang jiang Xiao-qiang Li Jin-tao Wang Hao Luo sheng-qing gao sheng-guan Qu Chao Yang National Engineering Research Centre of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640GuangdongChina Institute of New Materials Guangdong Academy of ScienceGuangzhou 510650GuangdongChina

To address the inhomogeneous microstructure and improve the mechanical properties of DT300 ultra-high strength steel specimens fabricated by laser powder bed fusion,different post-heat treatment schedules are *** the increase in austenitizing temperature and time,the migration rate of austenite grain boundaries continuously increases with the dissolution of nano-carbides,and the formation of nano-oxides and twin martensite is also inhibited *** rapid growth in the size of prior austenite grains and martensite laths,as well as the decrease in the content of nano-oxides and twin martensite,led to a rapid decrease in the strength(yield strength and ultimate tensile strength)from HT2 to HTF *** HT1 specimens(austenitizing at 830℃for 30 min,then oil quenching and tempering at 300℃for 120 min and finally air cooling)display excellent mechanical properties of yield strength of 1572 MPa,ultimate tensile strength of 1847 MPa,elongation of 9.84%,and fracture toughness of 106 MPa m^(1/2),which are counterparts to those of conventional DT300 steel forgings after heat treatment.

关键词： DT300 ultra-high strength steel Laser powder bed fusion-Short-time low-temperature austenitizing Microstructure Mechanical property

Muscle hypertrophy in transgenic mice due to over-expression of porcine myostatin mutated at its cleavage site

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Journal of Integrative Agriculture 2016年第11期15卷 2571-2577页

作者： QIAN Li-li MA de-zun gao Peng-fei jiang sheng-wang WANG qing-qing CAI Chun-bo XIAO gao-jun AN Xiao-rong CUI Wen-tao State Key Laboratory of Agrobiotechnology China Agricultural University State Key Laboratory for Animal Nutrition Institute of Animal ScienceChinese Academy of Agricultural Sciences

Myostatin, a member of the transforming growth factor beta（TGF-β） superfamily, is a dominant inhibitor that acts to limit skeletal muscle growth and development. In this study, we generated transgenic mice that express porcine myostatin containg mutations at its cleavage site（RSRR） to evaluate its effect on muscle mass. Results showed that the weight of four skeletal muscles including gastrocnemius, rectus femoris, tibialis anterior, and pectoralis increased by 17.83 and 28.39%, 21.76 and 28.70%, 34.31 and 41.62%, 53.21 and 27.54% in transgenic male and female mice, respectively, compared to their corresponding non-transgenic control mice. Measurement of muscle fiber size and number indicated that the mean myofiber size increased by 50.73 and 61.30% in transgenic male and female mice respectively compared to the non-transgenic controls. However, there was no difference in the number of myofiber between transgenic and non-transgenic male mice. These results clearly demonstrated that the increase in skeletal muscle mass in transgenic mice is caused by hypertrophy instead of hyperplasia.

关键词： porcine myostatin muscle mass transgenic mice mutation hypertrophy hyperplasia

The growth rate of hepatocellular carcinoma is different with different TNM stages at diagnosis

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Hepatobiliary & Pancreatic Diseases International 2021年第4期20卷 330-336页

作者： Tian-Ming gao Dou-sheng Bai Jian-Jun Qian Chi Zhang sheng-Jie Jin Guo-qing jiang department of Hepatobiliary Surgery Clinical Medical CollegeYangzhou UniversityYangzhou 225001China department of Hepatobiliary Surgery The Second Clinical CollegeDalian Medical UniversityDalian 116023China

Background: Hepatocellular carcinoma(HCC) progresses fast and has a poor prognosis, but the growth rate in different TNM stages is not clear. The present study was to estimate the growth rate of HCC with different TNM stages at diagnosis. Methods: Baseline demographics and tumor characteristics were analyzed for 10145 patients in Surveillance, Epidemiology, and End Results(SEER) Program-registered HCC. Multiple linear regression models were used for age adjustment with patient race, sex, marital status, and HCC grade. Results: The age at diagnosis was younger in Caucasians and males. The adjusted average age of patients with stage I HCC was 65.26 years. The adjusted age of patients with stage II, IIIA, IIIB, and IIIC was-0.17,-0.25,-0.29, and-0.55 adjusted-year younger compared with patients with stage I HCC(all P demonstrated that the more advanced the HCC stage at diagnosis, the younger the age at diagnosis and the faster the HCC growth from tumor occurrence.

关键词： Hepatocellular carcinoma Growth rate TNM stage SEER

Analysis of ice slurry production by direct contact heat transfer of air and water solution

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第8期14卷 583-588页

作者： xue-jun ZHANG Ke-qing ZHENG Ling-shi WANG Wei WANG Min jiang sheng-ying ZHAO Institute of Refrigeration and Cryogenics Zhejiang University School of Information and Electrical Engineering Zhejiang University City College

In this paper, a novel system using direct contact heat transfer between air and water solution was proposed to generate ice slurry. The heat transfer process and the system performance were studied; energy efficiency coefficients of 0.038, 0.053, and 0.064 were obtained using different solutions. An empirical relationship between the volumetric heat transfer coefficient U v and the main parameters was obtained by fitting the experimental data. The U v calculated from the empirical formula agreed with the experimental U v quite well with a relative error of less than 15%. Based on the empirical formula, a laboratory-scale direct contact ice slurry generator was then constructed, with practical application in mind. If the air flow rate is fixed at 200 m 3 /h, the ice production rate will be 0.091 kg/min. The experimental results also showed that the cold energy consumption of the air compressor accounted for more than half of the total amount. To improve the system energy efficiency coefficient, it is necessary to increase the air pipes insulation and the solution's thermal capacity, and also it is appropriate to utilize the free cold energy of liquefied natural gas (LNG).

关键词： Ice slurry Generator Air and water solution Direct contact Volumetric heat transfer coefficient Liquefied naturalgas (LNG)

EaIspF1, Essential Enzyme in Isoprenoid Biosynthesis from Eupatorium adenophorum, Reveals a Novel Role in Light Acclimation

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Journal of Integrative Agriculture 2014年第5期13卷 1024-1035页

作者： ZHANG sheng-rui jiang xue WANG Ping WU Di WANG qing-hua HOU Yu-xia College of Science China Agricultural University

Isoprenoids are a functionally and structurally diverse class of natural organic chemicals. The universal precursors of all isoprenoids, isopentenyl diphosphate and dimethylallyl diphosphate are synthesized through the mevalonate and 2C-methyl- D-erythritol 4-phosphate （MEP） pathways, respectively. Many isoprenoids produced through the MEP pathway play an important role in plant acclimation to different light environments. Eupatorium adenophorum, an invasive weed in China, presents a remarkable capacity to acclimate to various light environments, which constitutes its solid foundation of being a successful invasive species. Thus we aimed at gaining a deeper insight into the regulation of MEP pathway in E. adenophorum to further understand the invasive mechanism. 2C-Methyl-D-erythritol 2,4-cyclodiphosphate synthase （IspF or MCS） is an essential enzyme in the MEP pathway. In this paper, a novel IspF gene was cloned and characterized from E. adenophorum. Tissue-specific expression assays revealed a higher expression of EalspF1 in leaves than in stems and roots. The expression of EalspF1 was responsive to different light conditions. Some up-regulation of EalspF1 expression was also found after the treatments with signal compounds and after wounding stress. Interestingly, the over-expression of EalspF1 in Arabidopsis led to increase carotenoids contents, resulting in an enhanced tolerance to high light. Taken together, these results indicate that the EalspFl-derived enzyme participates in isoprenoid metabolism and among others, the expression of this gene in E. adenophorum is involved in the regulation of plastidial isoprenoids, which play an important role in acclimation to various light environments.

关键词： EalspF1 Eupatorium adenophorum isoprenoid biosynthesis light acclimation

Laboratory investigation on hydraulic fracture propagation in sandstone-mudstone-shale layers

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Petroleum Science 2022年第4期19卷 1664-1673页

作者： jiang-Chuan He Kuang-sheng Zhang Han-Bin Liu Mei-Rong Tang xue-Lin Zheng Guang-qing Zhang PetroChina Changqing Oilfield Company Xi′an710018ShaanxiChina College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China

During the stimulating unconventional reservoirs, the vertical propagation of hydraulic fractures is crucial for enlarging the stimulated reservoir volume, especially in multi-layers of sandstone, mudstone and shale(sand-mud-shale). To investigate the effects of lithological interface and fracturing fluid viscosity on the fracture propagation vertically in the multi-layers, hydraulic fracturing experiments in laboratory were performed on the outcrop samples of 30 cm × 30 cm × 30 cm collected from Yanchang Formation in Ordos Basin. The results show that hydraulic fractures are multi-branched and zig-zagged when they initiate in shale, simple when they commence in sandstone or mudstone. Hydraulic fractures created with low-viscosity fracturing fluid can only cross sandstone from mudstone, but those induced by high-viscosity fracturing fluid can cross the sand-mud-shale layers. Furthermore, the high-viscosity fracturing fluid reduces the fractures complexity in shale, facilitating vertical fracture propagation. The injection pressure fluctuates slightly as the hydraulic fracture extends from shale to sandstone or mudstone, otherwise it fluctuates significantly. From the laboratory investigation, a hydraulic fracturing scheme for Chang 7 Member was proposed, with its feasibility proved in field tests.

关键词： Sandstone-mudstone-shale Multi-layers Hydraulic fracturing experiments Lithological interface

A multi-fidelity prediction model for vertical bending moment and total longitudinal stress of a ship based on composite neural network

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Journal of Hydrodynamics 2023年第1期35卷 27-35页

作者： Cai-xia jiang Yu-bo Liu Zi-yuan Wang Shuai Chen sheng-ze Cai Qi gao xue-ming Shao Science and Technology on Advanced Composites in Special Environments Key Laboratory Harbin Institute of TechnologyHarbin150001China China Ship Scientific Research Center Wuxi214082China School of Aeronautics and Astronautics Zhejiang UniversityHangzhou310027China College of Control Science and Engineering Zhejiang UniversityHangzhou310027China

In ship engineering,the prediction of vertical bending moment(VBM)and total longitudinal stress(TLS)during ship navigation is of utmost *** this work,we propose a new prediction paradigm,the multi-fidelity regression model based on multi-fidelity data and artificial neural network(MF-ANN).Specifically,an ANN is used to learn the fundamental physical laws from low-fidelity data and construct an initial input-output *** predicted values of this initial model are of low accuracy,and then the high-fidelity data are utilized to establish a correction model that can correct the low-fidelity prediction ***,the overall accuracy of prediction can be improved *** feasibility of the multi-fidelity regression model is demonstrated by predicting the VBM,and the robustness of the model is evaluated at the same *** prediction of TLS on the deck indicates that just a small amount of high-fidelity data can make the prediction accuracy reach a high level,which further illustrates the validity of the proposed MF-ANN.

关键词： Artificial neural network multi-fidelity vertical bending moment total longitudinal stress

Pt-Te alloy nanowires towards formic acid electrooxidation reaction

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Journal of Energy Chemistry 2023年第10期85卷 481-489,I0013页

作者： Bin Sun Yu-Chuan jiang qing-Ling Hong xue Liu Fu-Min Li Dong-sheng Li Yun Yang Yu Chen Key Laboratory of Macromolecular Science of Shaanxi Province School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710062ShaanxiChina Nanomaterials and Chemistry Key Laboratory Wenzhou UniversityWenzhou 325035ZhejiangChina School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074HubeiChina College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002HubeiChina

The high-performance anodic electrocatalysts is pivotal for realizing the commercial application of the direct formic acid fuel *** this work,a simple polyethyleneimine-assisted galvanic replacement reaction is applied to synthesize the high-quality PtTe alloy nanowires(PtTe NW)by using Te NW as an efficient sacrificial *** existence of Te atoms separates the continuous Pt atoms,triggering a direct reaction pathway of formic acid electrooxidation reaction(FAEOR)at PtTe *** one-dimensional architecture and highly active sites have enabled PtTe NW to reveal outstanding electrocatalytic activity towards FAEOR with the mass/specific activities of 1091.25 mA mg^(-1)/45.34 A m^(-2)at 0.643 V potential,which are 44.72/23.16 and 20.26/11.75 times bigger than those of the commercial Pt and Pd nanoparticles,*** functional theory calculations reveal that Te atoms optimize the electronic structure of Pt atoms,which decreases the adsorption capacity of CO intermediate and simultaneously improves the durability of PtTe NW towards *** work provides the valuable insights into the synthesis and design of efficient Pt-based alloy FAEOR electrocatalysts.

关键词： Formic acid electrooxidation PtTe alloy nanowires Galvanic replacement reaction Reaction pathway Fuel cells