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Biomass chemical looping gasification for syngas production using modified hematite as oxygen carriers

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Journal of Environmental Sciences 2023年第3期125卷 171-184页

作者： cong Jiang Xiaoyu Jin Tingting Xu bo Xiao Zhiquan Hu Xun Wang School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China

Syngas is a clean energy carrier and a major industrial feedstock. In this paper, syngas was produced via biomass chemical looping gasification(CLG) process. Hematite, the most common Fe-based oxygen carrier(OC), was modified with different metal oxides(CeO_(2), CaO and MgO) by the impregnation method. The hematite modified by CeO_(2), CaO and MgO was namely as CeO_(2)-hematite(CeO_(2)-H), CaO-hematite(CaO-H) and MgO-hematite(MgO-H), respectively. The introduction of CeO_(2), CaO and MgO enhanced the reactivity of lattice oxygen of hematite. The optimum condition for syngas production had been explored as the mass ratio of oxygen carrier to biomass(O/B) of 0.2, the mass ratio of steam to biomass(S/B) of0.75 and temperature of 800℃in the biomass CLG process. The CeO_(2)-H exhibited the most wonderful performance compared to that for CaO-H and MgO-H. The crystal composition of OC influenced greatly in the CLG process. CeFeO_(3)had a good oxygen mobility property and lattice oxygen releasing capacity due to the most oxygen vacancy distributed on the OC surface and the most active lattice oxygen, which is conducive to the biomass chemical looping gasification process for syngas production, leading to the highest gasification efficiency of 95.86% and gas yield of 1.20 m^(3)/kg of the three. Cyclic test proved that CeO_(2)-H had well sintering resistance and cyclic performance.

关键词： Chemical looping gasification Oxygen carrier Syngas Modified hematite Pine sawdust

Impact of Plant Density on the Formation of Potato Mimitubers Derived from Microtubers and Tip-Cuttings in Plastic Houses

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Journal of Integrative Agriculture 2013年第6期12卷 1008-1017页

作者： JIN Hui LIU Jun SONG bo-tao XIE cong-hua Key Laboratory of Horticultural Plant Biology Ministry of Education/Potato Engineering Research Center of Hubei Province Huazhong Agricultural University

The potato minitubers have been widely used for the elite seed propagation to improve the seed potato system in China. However, little information is available for an efficient production of the minitubers with high plant density in the protected growing conditions like plastic houses. In present research, the minitubers of a wide-grown potato variety, Favorita, were produced with the microtubers from tissue culture and the tip-cuttings of the microtuber plants. Three plant densities, 200, 400 and 600 microtubers or plants m-2 were set up with the randomized block design of 3 replications and the experiment was repeated in 4 seasons in 2009-2010. The canopy development, light interception, dry weight production and partitioning, tuberization and tuber weight were investigated to elucidate the mechanism by which the plant density affects the formation and growth of the minitubers. The results showed that the number of the tubers formed per unite area was in line with the increase in plant density. The difference in leaf area index （LAI） between the plant densities, especially in early stage of the plant growth, resulted in more radiation interception and dry weight producing in higher plant density than in lower one. However, our analysis demonstrated that the conversion coefficient of the cumulative intercepted radiation to plant weight and the dry weight partition rate to the tubers were constant between plant densities, suggesting that less amount of the photoassimilates partitioned to individual tubers is causal for more small tubers in high plant density. A negative exponential curve model, determined by total number of tubers produced per unit area and the mean tuber weight, fitted well to the tuber size distribution pattern. The optimum plant density could be estimated from this model for a maximum production of the minitubers with desired size.

关键词： potato minituber microtuber tip-cutting plant density

Solitary necrotic nodules of the liver with"ring"-like calcification:A case report

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World Journal of Clinical Cases 2022年第21期10卷 7409-7414页

作者： Jin-Peng Bao Hu Tian Hao-Chen Wang cong-cong Wang bo Li Department of General Surgery The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qianfoshan HospitalJinan 250014Shandong ProvinceChina Department of Gastroenterology Shandong First Medical UniversityJinan 250024Shandong ProvinceChina Department of General Surgery Shandong Provincial Qianfoshan HospitalShandong UniversityJinan 250100Shandong ProvinceChina

BACKGROUND Solitary necrotic nodule of the liver(SNNL)is a rare benign lesion with a complete necrotic core and a clear fibrous capsule containing elastic *** present the case of a patient with a radiographic computed tomography(CT)finding of"ring"-like annular calcification within the lesion and postoperative pathologic diagnosis of necrotic nodules wrapped by dense fibers in liver tissue,as well as the patient's subsequent management and *** SUMMARY A 38-year-old Chinese woman with a history of systemic lupus erythematosus treated with prednisone and hydroxychloroquine,without any symptoms,was found to have hepatic space-occupying lesions by imaging examination at a health examination.A subsequent CT scan suggested a space-occupying lesion of the liver with annular calcification,which was not defined to be benign or *** that,a laparoscopic hepatic space-occupying resection was *** postoperative pathological diagnosis was necrotic nodules wrapped by dense fibers in the liver tissue,and the final diagnosis was *** patient had an uneventful postoperative *** There is a"ring"-like calcification in *** patient had a history of systemic lupus erythematosus,without a history of parasite infection,trauma,or ***,whether the etiology and pathological changes of SNNL are related to rheumatic immune diseases remains to be investigated.

关键词： Solitary necrotic nodules of the liver Annular calcification Rheumatic immune disease Laparoscopic hepatic space-occupying resection Case report

Joint power allocation and relay selection for decode-and-forward cooperative relay in secure communication

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 79-85页

作者： YANG Yun-chuan ZHAO Hui SUN cong WANG Wen-bo Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications ICMSEC AMSS Chinese Academy of Sciences

In this paper, we investigate the cooperative strategy with total power constraint in decode-and-forward （DF） relaying scenario, in the presence of an eavesdropper. Due to the difference of channel for each source-relay link, not all relay nodes have constructive impacts on the achievable secrecy rate. Besides, the final achieved secrecy rate depends on both source-relay and relay-destination links in DF relaying scenario. Therefore, the principal question here is how to select cooperative strategy among relays with proper power allocation to maximize the secrecy rate. Three strategies are considered in this paper. First, we investigate the cooperative jamming （CJ） strategy, where one relay with achieved target transmission rate is selected as a conventional relay forwarding signal, and remaining relays generate artificial noise via CJ strategy to disrupt the eavesdropper. Two CJ schemes with closed-form solutions, optimal cooperative jamming （OCJ） and null space cooperative jamming （NSCJ）, are proposed. With these solutions, the corresponding power allocation is formulated as a geometric programming （GP） problem and solved efficiently by convex programming technique. Then, to exploit the cooperative diversity, we investigate the cooperative relaying （CR） strategy. An iterative algorithm using semi-definite programming （SDP） and GP together with bisection search method is proposed to optimize the cooperative relaying weight and power allocated to the source and relays. Furthermore, to exploit the advantages of both CR and CJ, we propose an adaptive strategy to enhance the security. Simulation results demonstrate that the efficiency of the proposed cooperative strategies in terms of secrecy rate.

关键词： physical layer security CJ CR power allocation SDP GP

Status of Serum Uric Acid and Hyperuricemia among Adults in China:China Nutrition and Health Surveillance(2015)

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Biomedical and Environmental Sciences 2022年第10期35卷 911-920页

作者： PIAO Wei bo Ya cong ZHAO Li Yun YU Dong Mei Key Laboratory of Trace Element Nutrition of National Health Commission National Institute of Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China The First Affiliated Hospital of Zhengzhou University Zhengzhou 450000HenanChina

Objective The purpose of this study was to determine the serum uric acid levels and the prevalence of hyperuricemia among Chinese adults in 2015 and compare the differences between urban and rural areas,as well as the differences between eastern,central,and western *** A national representative sample of 180,208 participants were included using a stratified,multistage,and random sampling *** demographic characteristics and blood samples were collected to determine the serum uric acid levels and prevalence of hyperuricemia among subgroups using complicated sampling weight.A t-test or ANOVA was used for normally-distributed *** Kruskal-Wallis rank test was used for skewed-distributed *** Mantel-Haenszel chi-square test was used to compare the difference in categorical *** The weighted mean uric acid level in Chinese adults was 310.4μmol/L(317.5μmol/L in urban areas and 302.9μmol/L in rural areas).The weighted average values of uric acid in eastern,central,and western China were 315.5μmol/L,303.5μmol/L,and 310.4μmol/L,*** weighted prevalence of hyperuricemia in Chinese adults was 14.6%,with a prevalence of 16.5%in urban areas and12.5%in rural *** weighted prevalence of hyperuricemia in eastern,central,and western China was 16.0%,12.5%,and 14.8%,*** The uric acid level in Chinese adults is relatively *** actions are warranted to improve this metabolic abnormality.

关键词： Uric acid Hyperuricemia Adults China

Microstructures and grain refinement performance of Al-Ti-B-C grain refiner via powder metallurgy

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Rare Metals 2022年第7期41卷 2357-2362页

作者： cong Xu Wen-Long Xiao Shi-Zhen Wen yue-Jun Zhen Chao-Li Ma Key Laboratory of Aerospace Advanced Materials and Performance of Ministry of Education School of Material Science and EngineeringBeihang UniversityBeijing 100191China Lizhong Group Baoding Lizhong Wheel Manufacturing Co.Ltd.Baoding 071000China

The Al-5Ti-0.5B-0.5C grain refiner was pre-pared by powder metallurgy(PM).Microstructures of the grain refiner and its grain refinement performance in commercially pure aluminum(Al)were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM),and differential scanning calorimetry(DSC).It is found that the average grain size of commercially pure Al can be reduced from~15,000 to~180μm by the addition of Al-5Ti-0.5B-0.5C grain refiner prepared by PM,based on 0.01 wt%Ti *** grain refinement efficiency begins to decrease slightly when the grain refiner is kept in the melt for 60 *** grain refinement is attributed to high stability,proper size,and high density of Al3Ti,TiB2,and TiC particles.

关键词： Al–Ti–B–C Powder metallurgy Microstructure Grain refinement

Metastable face-centered cubic ruthenium-based binary alloy for efficient alkaline hydrogen oxidation electrocatalysis

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Journal of Energy Chemistry 2024年第5期92卷 207-215页

作者： Yunbo Li Jianchao yue Chaoyi Yang Hongnan Jia Hengjiang cong Wei Luo College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072HubeiChina

Metastable nanostructured electrocatalyst with a completely different surface environment compared to conventional phase-based electrocatalyst often shows distinctive catalytic *** Ru-based electrocatalysts have been widely investigated toward hydrogen oxidation reaction(HOR)under alkaline electrolytes,these studies are mostly limited to conventional hexagonal-close-packed(hcp)phase,mainly arising from the lack of sufficient synthesis *** this study,we report the precise synthesis of metastable binary RuW alloy with face-centered-cubic(fcc)*** find that the introduction of W can serve as fcc phase seeds and reduce the formation energy of metastable fcc-RuW ***,fcc-RuW exhibits remarkable alkaline HOR performance and stability with the activity of 0.67 mA cm_(Ru)^(-2)which is almost five and three times higher than that of hcp-Ru and commercial Pt/C,respectively,which is attributed to the optimized binding strength of adsorbed hydroxide intermediate derived from tailored electronic structure through W doping and phase ***,this strategy can also be applied to synthesize other metastable fcc-RuCr and fcc-RuMo alloys with enhanced HOR performances.

关键词： Hydrogen oxidation reaction Metastable phase Face-centered cubic(fcc) Ru Phase engineering

Coupling relationship between multicomponent recovery of rare earth tailings

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Rare Metals 2017年第3期36卷 220-228页

作者： yue Zhang Hai Lin Ying-bo Dong Xiao-Fang Xu Xin Wang yue-Jiao Gao School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of High-Efficient Mining and Safety of Metal Mines Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083China

About 90 % rare earth minerals and many other valuable minerals are heaped as iron tailings without comprehensive utilization. In order to comprehensively recover these valuable minerals, in a view of the valuable ore type of Baotou Steel tailing and embedded features, valuable components flow and their respective recovery coupling relationship in beneficiation flowsheet were ana- lyzed; process flows and parameters which could give consideration to four kinds of components were deter- mined. TFe, rare earth oxide （REO）, niobium and fluorite recoveries could reach 72.70 %, 81.84 %, 78.58 % and 60.18 % in low-intensity/high-intensity magnetic separa- tion, respectively. High-intensity magnetic concentration was treated by REO direct flotation; the recovery is 75.43 %, on the base of which Fe could be separated completely from Nb. The underflow was treated by reduction roasting-low-intensity magnetic separation. And the relationship between the recoveries of these valuable components was also discussed.

关键词： Rare earth tailings Recovery Couplingrelationship

The current state of acupuncture treatment for inflammatory arthritis

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TMR Non-Drug Therapy 2023年第3期6卷 18-19页

作者： cong-yue Bi bo Wen School of Basic Medicine Beijing University of Chinese MedicineBeijing 100105China Department of Rheumatology Beijing Traditional Chinese Medicine HospitalCapital Medical UniversityBeijing 100010China

Inflammatory arthritis refers to the migration of inflammatory cells(such as monocytes/macrophages,lymphocytes,and granulocytes)from the blood to the synovium or synovial fluid,causing joint pain and *** is often associated with decreased joint mobility and functional *** diseases lead to cartilage and skeletal damage,resulting in joint *** inflammatory arthritis includes rheumatoid arthritis,ankylosing spondylitis,and gout.

关键词： acupuncture inflammatory damage