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NUMERICAL PREDICTION OF CROSS FLOW IN UNHEATED FURNACE

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Journal of Hydrodynamics 1991年第3期3卷 68-73页

作者： jian-ren, Fan Qiang, hua Ke-li, zeng Ke-fa, Cen Zhejiang Univ Hangzhou China

This paper describes the results of a finite-difference solution for the three-dimensional flow field generated by a rectangular turbulent jet (secondary air) deflected by a main stream (primary air) in an unheated furnace. The essential properties of cross flow are discussed in the case of different shapes of the rectangular orifice, ratios of the secondary air injected velocity to the primary air velocity, and different injection angles. Last, two correlations equations are obtained and the numerical predictions are shown to demonstrate the good agreement with the experimental data.

关键词： Computers Applications Fluid Mechanics Furnaces Mathematical Models

Effects of long-term straw return on soil organic carbon fractions and enzyme activities in a double-cropped rice paddy in South China

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Journal of Integrative Agriculture 2021年第1期20卷 236-247页

作者： huaNG Wan WU jian-fu PAN Xiao-hua TAN Xue-ming zeng Yong-jun SHI Qing-hua LIU Tao-ju zeng Yan-hua Key Laboratory of Crop Physiology Ecology and Genetic BreedingMinistry of Education/Collaborative Innovation Center for the Modernization Production of Double Cropping Rice/College of AgronomyJiangxi Agricultural UniversityNanchang 330045P.R.China

Long-term straw return is an important carbon source for improving soil organic carbon(SOC) stocks in croplands, and straw removal through burning is also a common practice in open fields in South China. However, the specific effects of long-term rice straw management on SOC fractions, the related enzyme activities and their relationships, and whether these effects differ between crop growing seasons remain unknown. Three treatments with equal nitrogen, phosphorus, and potassium nutrient inputs, including straw/ash and chemical nutrients, were established to compare the effects of straw removal(CK), straw return(SR), and straw burned return(SBR). Compared to CK, long-term SR tended to improve the yield of early season rice(P=0.057), and significantly increased total organic carbon(TOC) and microbial biomass carbon(MBC) in double-cropped rice paddies. While SBR had no effect on TOC, it decreased light fraction organic carbon(LFOC) in early rice and easily oxidizable organic carbon(EOC) in late rice, significantly increased dissolved organic carbon(DOC), and significantly decreased soil p H. These results showed that MBC was the most sensitive indicator for assessing changes of SOC in the double-cropped rice system due to long-term straw return. In addition, the different effects on SOC fraction sizes between SR and SBR were attributed to the divergent trends in most of the soil enzyme activities in the early and late rice that mainly altered DOC, while DOC was positively affected by β-xylosidase in both early and late rice. We concluded that straw return was superior to straw burned return for improving SOC fractions, but the negative effects on soil enzyme activities in late rice require further research.

关键词： double-cropped rice paddy system straw return straw burned return SOC fractions soil enzyme activities

Pharmacological targeting cGAS/STING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3287-3301页

作者： Ziwei Fan Mengxian Jia jian Zhou Zhoule Zhu Yumin Wu Xiaowu Lin Yiming Qian Jiashu Lian Xin hua jianhong Dong Zheyu Fang Yuqing Liu Sibing Chen Xiumin Xue Juanqing Yue Minyu Zhu Ying Wang Zhihui huang Honglin Teng Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Neurology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina

The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord *** of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be *** possesses an anti-inflammatory biological ***,its roles and the underlying molecular mechanisms in spinal cord injury remain *** this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in *** promoted M2 polarization through inactivating the cGAS/STING/NF-κB ***,we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord ***,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal *** together,these results suggest that by targeting the cGAS/STING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype.

关键词： cGAS/STING functional recovery microglia neuroinflammation neuroprotection nuclear factor-κB polarization spinal cord injury tryptanthrin

Interrogating imaginary optical force by the complex Maxwell stress tensor theorem

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Light(Science & Applications) 2023年第1期12卷 12-14页

作者： Jinwei zeng jian Wang Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074 HubeiChina Optics Valley Laboratory Wuhan 430074 HubeiChina

The complex Maxwell stress tensor theorem has been developed to relate the imaginary optical force,reactive strength of canonical momentum and total optical force of a nanoparticle,which is essential to perfect optica... 详细信息

关键词： imaginary tensor theorem

Rational formulation of modern geoid concept

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中国有色金属学会会刊：英文版 2011年第S3期21卷 675-680页

作者： GUO zeng-zhang, XIAO jian-hua Geodesy Institute, Henan Polytechnic University, Jiaozuo 454000, China Geodesy Institute Henan Polytechnic University Jiaozuo 454000 China

Based on modern geometrical field theory, a rational interpretation of modern geodesic surface concept was formulated. The general equations for geodesic surface were given. The height concept and arc length concept were formulated strictly. Their intrinsic benefits and shortages of parameter-center reference and mass-center reference systems were studied in details. The research results show that the geodesic concept depends on the available technology. The technology-dependence feature of geodesy concept was expressed by related mathematic formulations. For the satellite-based observation system, the rationality of China-2000 Geoid Reference System was explained. Discussions about how to establish regional precision reference system were made based on general equations of arc length and space distance equations. A new correction item should be taken into consideration for arc length gauge calculation.

关键词： geodesic surface parameter-center system mass-center system geodesy deformation geoid

Heptanuclear brucite disk with cyanide bridges in a cocrystal and tracking its pyrolysis to an efficient oxygen evolution electrode

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Science Bulletin 2019年第22期64卷 1667-1674页

作者： jian-Qiang Zhao Dandan Cai Jun Dai Mohamedally Kurmoo Xu Peng Ming-hua zeng Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources Department of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062China Institut de Chimie de Strasbourg CNRS-UMR7177Universite de Strasbourg67070 Strasbourg CedexFrance

The development of efficient oxygen evolution reaction(OER)catalysts is still lacking in exploration of the mechanism of controlled pyrolysis of precursors among new material ***,a novel Co-based coordination molecular cluster has been first introduced as precursor to obtain metallic cobalt core shelled by N-doped carbon(Co@NC)structure which operates as an oxygen evolution ***,a new cocrystal compound,[Co7II(l3-CN)6(mmimp)6][CoIICl3N(CN)2]á3CH3OH(Co7+1,mmimp=2-methoxy-6-((methylimino)-methyl)phenol),was isolated consisting of Brucite disks of cobalt where the usual bridging l3-OH is replaced by l3-CN produced by the in-situ decomposition of dicyanamide(NC-N-CNà).The cobalt atoms are bonded through the nitrogen atom of the ***,time dependent thermogravimetric-mass spectrometry(TG-MS)analysis was utilized to track its pyrolysis *** allowed us to propose a possible formation process of the Co@NC structure from Co7+***,an extremely superior OER electrode is optimized for Co@NC-600 having the lowest overpotential of257 m V at 10 m A/cm2in 1 mol/L KOH *** present study pins down the importance of clusters of transition metals on realizing distinct nanostructures operating as highly efficient OER electrocatalyst.

关键词： Cobalt disk clusters Thermogravimetry-mass spectrometry Pyrolysis tracking Core-shell nanostructure Oxygen evolution reaction

Short-range disorder in MOF glasses

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National Science Review 2021年第5期8卷 13-14页

作者： Ming-hua zeng Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal University Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesHubei University

Glass appears to be an ordinary material with wide applications in daily life and industry; however, its formation mechanism, phase transition and microscopic structure remain mysterious. It is accepted to be an amorphous solid exhibiting glass transition, with short-range(20?A)disorder structures [1]. Experimental determination of the structure of glass is crucial to understand its dynamic and physical properties.‘What is the nature of glass?’ is one of the most fundamental and challenging scientific questions [1].

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Production and Properties of a Thickener with Ability of Suspending Sand

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Journal of China University of Mining and Technology 2006年第2期16卷 115-118,122页

作者： QIN Bo-tao WANG De-ming LI zeng-hua CHEN jian-hua School of Mineral and Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

To overcome the shortcomings of pouring sands, a thickener with the ability to suspend sands was developed. It is mixed with sands to form densified slurry, and can insure the sands against deposition, jamming pipelines and de- hydration. The chemical structure of the thickener is introduced in this paper and the production process is studied. The main processes include immersion, decomposition, dilution and addition of additives. In order to produce a thickener with high viscosity to suspend sands, key factors must be controlled in each process: the immersion time is 2 h; the mass fraction of formaldehyde is 0.01% and mass of NaCO3 accounts for 15% of dry material; the water temperature is 65 ℃ in summer and 72 ℃ in winter and the decomposition time is 2 h in the reaction; the densified decomposition so- lution should be diluted to 1% mass fraction; the additives of calcium ions and pH indicators must be added to the di- luted liquid; the mass fraction of CaCl2 is 0.048% and the pH value of the solution is 7.5. The thickener is a gel with three-dimensional network structure, a liquid with non-Newtonian behaviour and the characteristics of pseudo-plastic material, a solution with little resistance and the ability to revive its oral primary viscosity. It has been successfully ap- plied in Shendong Mines and has great value and wide-spread prospective use.

关键词： thickener ability of suspending sand spontaneous combustion of coal

Polypropylene crisper and 1-MCP delay the softening,lignification and transcription levels of related enzyme genes of golden needle mushrooms(Flammulina velutipes)

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Journal of Integrative Agriculture 2022年第1期21卷 249-260页

作者： WANG Wen-jun LI Yao LI Fu-hua zeng Kai-fang MING jian College of Food Science Southwest UniversityChongqing 400715P.R.China Research Center of Food Storage&Logistics Southwest UniversityChongqing 400715P.R.China

The fresh postharvest golden needle mushroom(Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality *** with 1-methylcyclopropene(1-MCP) and polypropylene(PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage. The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes;either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase(PAL), cinnamyl alcohol dehydrogenase(CAD), cellulase(Cx), pectin methylesterase(PME) and polygalacturonase(PG). Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best. The results of transmission electron microscopy(TEM) and scanning electron microscopy(SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture. The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes. In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.

关键词： Flammulina velutipes polypropylene crisper 1-MCP softening and lignification transcription levels