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Prediction of suitable water content in granulation of sintering mixture based on Litster's model

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Journal of Iron and Steel Research(International) 2024年第3期31卷 552-560页

作者： Fang-lei Dai Xiao-hui Fan Xiao-xian Huang Xu-ling Chen Min Gan Zhi-yun Ji Zeng-qing Sun School of Minerals Processing and bioengineering Central South UniversityChangsha 410083HunanChina

Suitable water content plays a decisive role in the granulation of sintering mixtures.Herein,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation model.The granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were studied.The results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water content.With an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation effectiveness.Moreover,as the amount of concentrates increased,the suitable water content first increased and then remained steady.The influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.

关键词： Adhesive particle Sintering mixture Granulation effectiveness Suitable water content

Exploring binding mode for styrylquinoline HIV-1 integrase inhibitors using comparative molecular field analysis and docking studies

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Acta Pharmacologica Sinica 2004年第7期25卷 104-112页

作者： Xiao-hui MA, Xiao-yi ZHANG, Jian-jun TAN, Wei-zu CHEN, Cun-xin WANG2 College of LifeScience and bioengineering, Beijing University of Technology, Beijing 100022, China College of Life Science and bioengineering Beijing University of Technology 北京 100022

AIM: To understand pharmacophore properties of styrylquinoline derivatives and to design inhibitors of HIV-1 integrase. METHODS: Comparative molecular field analysis (CoMFA) was performed to analyze three-dimen- sional quantitative structure-activity relationship (3D-QSAR) of styrylquinoline derivatives. Thirty-eight compounds were randomly divided into a training set of 28 compounds and a test set of 10 compounds. The stability of 3D- QSAR models was proved by the analysis of cross-validated and non-cross-validated methods. Moreover, the binding mode of these compounds and integrase was constructed by AutoDock program. RESULTS: The CoMFA model of the training compounds was reasonably predicted with cross-validated coefficient (q2) and conventional (r2) values (up to 0.696 and 0.754). Then the model was validated by the test set. The resulting CoMFA maps visualized structural requirements for the biological activity of these inhibitors. Docking results showed that a carboxyl group at C-7 and a hydroxyl group at C-8 in the quinoline subunit, bound closely to the divalent metal cofactor (Mg2+) around the integrase catalytic site. Moreover, there is a linear correlation between the binding energy of the inhibitors with integrase and their inhibitory effect. CONCLUSIONS: The present study indicated that the CoMFA model together with docking results could give us helpful hints for drug design as well as interpre- tation of the binding affinity between these inhibitors and integrase.

关键词： HIV integrase inhibitors quinolines comparative molecular field analysis AutoDock

Super-high bed sintering for iron ores:problems ascertainment

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1063-1070页

作者： Liang-ping Xu Hui-bo Liu Yu-chao Zhao Qiang Zhong Zhong-lin Dong Guang-hui Li Tao Jiang School of Minerals Processing and bioengineering Central South UniversityChangsha410083HunanChina

Super-high bed sintering process is an important development direction of iron ore sintering for its lower emission and higher yield.However,there is a lack of deep understanding of the uneven quality of super-high bed sintering products,and the deterioration of reduction disintegration performance,the thickening of hearth layer and the reduction in energy-saving effect are perplexing enterprises and researchers.To ascertain the problems of super-high bed sintering,ten sintering machines with the areas of 265,280,360,550 and 660 m^(2)and bed depth above 900 mm were sampled and analyzed.The results showed that problems were mainly shown in the unevenness of chemical composition,macrostructure,mechanical strength and metallurgical performance.The chemical composition exhibits severe segregation in both horizontal and vertical directions,with basicity segregation reaching as high as 0.81.The uneven macrostructure of sinter is reflected in a 10%difference in porosity and mechanical strength increase in 16%–19%along the vertical direction.The reducibility and reduction disintegration performance gradually deteriorate along the bed depth,with a difference of 10.5%in reducibility and 7.3%in RDI−0.5 mm(reduction disintegration index of sinter with size smaller than 0.5 mm).

关键词： Super-high bed sintering Uneven sinter performance Segregation Agglomeration Iron ore

QUANTITATIVE PATTERN RECOGNITION FOR STRUCTURE-CARCINOGENIC ACTIVITY RELATIONSHIP OF N-NITROSO COMPOUNDS BASED UPON DI-REGION THEORY

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Science China Chemistry 1989年第7期32卷 776-790页

作者：戴乾圜钟儒刚 Center for Chemistry & bioengineering of Cancer Beijing Polytechnic University

In this paper, it is evidenced by the quantitative structu re-carcinogenic activity relation-ship (QSCAR) and the pattern recognition treatment of N-nitroso compounds (NNC) that thekey step of carcinogenesis induced by NNC is the cross-linking on the complementary basepair of DNA, through the bifunctional alkylation between α-carbon and another carbonwithin the same chain. The alkylation by the α-carbon atom is through the diazonium salt,but that by the atom other than the α-position is through the active ester formed from thehydroxylated metabolite of the chain. Therefore, the alkylation by the β-position of NNC,or by its γ-position under suitable conditions, of which the distances from the α-positionboth approach 2. 80-3. 00 A, would be the most favourable positions along with the α-posi-tion for the cross-linking to occur between the complementary base pairs of DNA, whichwill yield the carcinogenic activity of NNC. The above conception of bifunctional alkyla-tion can reduce the QSCAR of NNC

关键词： N-nitroso compounds Di-region theory pattern recognition chemical carcinogenesis structure-carcinogenic activity relationship

Harness High-Temperature Thermal Energy via Elastic Thermoelectric Aerogels

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Nano-Micro Letters 2024年第8期16卷 196-210页

作者： Hongxiong Li Zhaofu Ding Quan Zhou Jun Chen Zhuoxin Liu Chunyu Du Lirong Liang Guangming Chen College of Materials Science and Engineering Shenzhen UniversityShenzhen 518055People’s Republic of China Department of bioengineering University of CaliforniaLos AngelesCA 90095USA

Despite notable progress in thermoelectric(TE)materials and devices,developing TE aerogels with high-temperature resistance,superior TE performance and excellent elasticity to enable self-powered high-temperature monitoring/warning in industrial and wearable applications remains a great challenge.Herein,a highly elastic,flame-retardant and high-temperature-resistant TE aerogel,made of poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate)/single-walled carbon nanotube(PEDOT:PSS/SWCNT)composites,has been fabricated,displaying attractive compression-induced power factor enhancement.The as-fabricated sensors with the aerogel can achieve accurately pressure stimuli detection and wide temperature range monitoring.Subsequently,a flexible TE generator is assembled,consisting of 25 aerogels connected in series,capable of delivering a maximum output power of 400μW when subjected to a temperature difference of 300 K.This demonstrates its outstanding high-temperature heat harvesting capability and promising application prospects for real-time temperature monitoring on industrial high-temperature pipelines.Moreover,the designed self-powered wearable sensing glove can realize precise wide-range temperature detection,high-temperature warning and accurate recognition of human hand gestures.The aerogel-based intelligent wearable sensing system developed for firefighters demonstrates the desired self-powered and highly sensitive high-temperature fire warning capability.Benefitting from these desirable properties,the elastic and high-temperature-resistant aerogels present various promising applications including self-powered high-temperature monitoring,industrial overheat warning,waste heat energy recycling and even wearable healthcare.

关键词： Thermoelectrics Aerogel Self-powered High-temperature monitoring High-temperature warning

Artificial intelligence optimization and controllable slow-release iron sulfide realizes efficient separation of copper and arsenic in strongly acidic wastewater

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Journal of Environmental Sciences 2024年第5期139卷 293-307页

作者： Xingfei Zhang Chenglong Lu Jia Tian Liqiang Zeng Yufeng Wang Wei Sun Haisheng Han Jianhua Kang School of Minerals Processing and bioengineering Central South UniversityChangsha 410083China Centre for Mined Land Rehabilitation Sustainable Minerals InstituteThe University of QueenslandBrisbane 4072Australia

Iron sulfide(FeS)is a promising material for separating copper and arsenic from strongly acidic wastewater due to its S^(2-)slow-release effect.However,uncertainties arise because of the constant changes in wastewater composition,affecting the selection of operating parameters and FeS types.In this study,the aging method was first used to prepare various controllable FeS nanoparticles to weaken the arsenic removal ability without affecting the copper removal.Orthogonal experiments were conducted,and the results identified the Cu/As ratio,H_(2)SO_(4) concentration,and FeS dosage as the three main factors influencing the separation efficiency.The backpropagation artificial neural network(BP-ANN)model was established to determine the relationship between the influencing factors and the separation efficiency.The correlation coefficient(R)of overall model was 0.9923 after optimizing using genetic algorithm(GA).The BP-GA model was also solved using GA under specific constraints,predicting the best solution for the separation process in real-time.The predicted results show that the high temperature and long aging time of FeS were necessary to gain high separation efficiency,and the maximum separation factor can reached 1,400.This study provides a suitable sulfurizing material and a set of methods and models with robust flexibility that can successfully predict the separation efficiency of copper and arsenic from highly acidic environments.

关键词： FeS nanoparticles Aging Sulfide precipitation Orthogonal experiment Artificial neural network Prediction

The two sides of chromosomal instability:drivers and brakes in cancer

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1595-1624页

作者： Rendy Hosea Sharon Hillary Sumera Naqvi Shourong Wu Vivi Kasim Key Laboratory of Biorheological Science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqing 400045China The 111 Project Laboratory of Biomechanics and Tissue Repair College of BioengineeringChongqing UniversityChongqing 400044China Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing UniversityChongqing 400030China

Chromosomal instability(CIN)is a hallmark of cancer and is associated with tumor cell malignancy.CIN triggers a chain reaction in cells leading to chromosomal abnormalities,including deviations from the normal chromosome number or structural changes in chromosomes.CIN arises from errors in DNA replication and chromosome segregation during cell division,leading to the formation of cells with abnormal number and/or structure of chromosomes.Errors in DNA replication result from abnormal replication licensing as well as replication stress,such as double-strand breaks and stalled replication forks;meanwhile,errors in chromosome segregation stem from defects in chromosome segregation machinery,including centrosome amplification,erroneous microtubule-kinetochore attachments,spindle assembly checkpoint,or defective sister chromatids cohesion.In normal cells,CiN is deleterious and is associated with DNA damage,proteotoxic stress,metabolic alteration,cell cycle arrest,and senescence.Paradoxically,despite these negative consequences,CiN is one of the hallmarks of cancer found in over 90%of solid tumors and in blood cancers.Furthermore,CiN could endow tumors with enhanced adaptation capabilities due to increased intratumor heterogeneity,thereby facilitating adaptive resistance to therapies;however,excessive CiN could induce tumor cells death,leading to the"just-right"model for CIN in tumors.Elucidating the complex nature of CIN is crucial for understanding the dynamics of tumorigenesis and for developing effective anti-tumor treatments.This review provides an overview of causes and consequences of CIN,as well as the paradox of CIN,a phenomenon that continues to perplex researchers.Finally,this review explores the potential of CIN-based anti-tumor therapy.

关键词： chromosomal consequences thereby

Grain Growth Kinetics of SnO_2 Nanocrystals Synthesized by Precipitation Method

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Journal of Wuhan University of Technology(Materials Science) 2010年第6期25卷 929-934页

作者：宋晓岚 School of Minerals Processing and bioengineering Central South University

Monodispersed spheroidal SnO2 nanocrystals with the grain size of 8-30 nm were synthesized by the precipitation method using SnCl4·5H2O （stannic chloride hydrate） as raw materials.Differential scanning calorimetry/thermogravimetry （DSC/TG）,X-ray diffraction （XRD） and transmission electron microscope （TEM） were used to characterize the structure of SnO2 nanocrystals.The influences of the calcination temperature and time on the lattice constant,the lattice distortion and the grain size of SnO2 nanocrystals were discussed based on the XRD results.The grain growth kinetics of SnO2 nanocrystals during calcination process was simulated with a conventional grain growth model which only took into account of diffusion and with a new isothermal model proposed by our group,which took into account of both diffusion and surface reactions.Using conventional model,the grain growth rate constant of SnO2 crystals is 1.55×104nm5/min with a pre-exponential factor of 5 and an activation energy of 108.62 kJ/mol.Compared with the convention model,the new isothermal model is more realistic in reflecting the grain growth behavior of SnO2 nanocrystals during the calcination process.This indicates that the grain growth of SnO2 nanocrystals is controlled by both diffusion and reaction factors,and the effect of surface reactivity on the grain growth of SnO2 nanocrystals could not be ignored.A combined activation energy estimated with the new isothermal model is 53.46 kJ/mol.

关键词： SnO2 nanocrystal precipitation method calcination grain growth kinetics

In vitro engineered models of neurodegenerative diseases

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BIOCELL 2024年第1期48卷 79-96页

作者： ZEHRA GÜL MORÇIMEN ŞEYMA TAŞDEMIR AYLIN ŞENDEMIR bioengineering Department Graduate School of Natural and Applied SciencesEge UniversityIzmir35040Türkiye bioengineering Department Faculty of Engineering and Natural ScienceCelal Bayar UniversityManisa45110Türkiye bioengineering Department Ege UniversityIzmir35040Türkiye Department of Biomedical Technologies Graduate School of Natural and Applied SciencesEge UniversityIzmir35040Türkiye

Neurodegeneration is a catastrophic process that develops progressive damage leading to functional andstructural loss of the cells of the nervous system and is among the biggest unavoidable problems of our age.Animalmodels do not reflect the pathophysiology observed in humans due to distinct differences between the neuralpathways,gene expression patterns,neuronal plasticity,and other disease-related mechanisms in animals andhumans.Classical in vitro cell culture models are also not sufficient for pre-clinical drug testing in reflecting thecomplex pathophysiology of neurodegenerative diseases.Today,modern,engineered techniques are applied to developmulticellular,intricate in vitro models and to create the closest microenvironment simulating biological,biochemical,and mechanical characteristics of the in vivo degenerating tissue.In THIS review,the capabilities and shortcomings ofscaffold-based and scaffold-free techniques,organoids,and microfluidic models that best reflect neurodegeneration invitro in the biomimetic framework are discussed.

关键词： Neurodegenerative diseases In vitro models Scaffolds Organoids Microfluidic devices