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Petroleum Science 2022年第2期19卷 916-926页

作者： Jing-Ping Liu xian-Fa zhang Wen-Chao zhang Kai-he Lv Yin-Rui Bai Jin-Tang Wang xian-Bin Huang Jia-Feng Jin Jin-Sheng Sun College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China CNPC Engineering Technology R&D Company Limited Beijing 102206China

Drilling fluids face failure during drilling deep reservoir with high temperature and high *** experimental results show that high temperature and salinity reduce the negative charge on the surface of bentonite in the drilling fluid and cause the coalescence of bentonite *** a result,the particles coalesce,the grid structure is destroyed,and the rheological properties,rock-carrying capacity and filtration properties are *** resolve the foregoing,in this study,0.05-wt%carbon nanotubes are introduced into a 4%bentonite drilling fluid under conditions where the temperature and concentration of added Na Cl reach 180°C and 10 wt%,*** carbon nanotubes adsorb on the bentonite surface and increase the space among bentonite *** steric hindrance prevents the coalescence of bentonite in high temperature and high salt *** bentonite maintains the small size distribution of bentonite and supports the bentonite grid structure in the drilling *** a result,the rock-carrying capacity of the drilling fluid increases by 85.1%.Moreover,the mud cake formed by the accumulation of small-sized bentonite particles is dense;consequently,the filtration of bentonite drilling fluid reduced by 30.2%.

关键词： High temperature Water-based drilling fluid High salinity Carbon nanotube Deep resources

M6A modification of circNSUN2 promotes colorectal liver metastasis

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Genes & Diseases 2021年第1期8卷 6-7页

作者： Rong-zhang he Jing Jiang Di-xian Luo Department of Clinical Pharmacology Xiangya HospitalCentral South UniversityChangshaHunan410078PR China Translational Medicine Institute National&Local Joint Engineering Laboratory for High-through Molecular Diagnosis TechnologyCollaborative Research Center for Post-doctoral Mobile Stations of Central South UniversityAffiliated the First People’s Hospital of ChenzhouUniversity of South ChinaChenzhouHunan423000PR China Center for Clinical Pathology The First People’s Hospital of ChenzhouUniversity of South ChinaChenzhouHunan423000PR China

Circular RNAs(circRNAs)are playing emerging role in the pathogenesis of cancers,but the mechanisms still *** the recent issue of the Nature Communications,Chen and colleagues have demonstrated that YTHDC1 facilitates N6-methyladenosine modified circNSUN2 cytoplasmic export and the circNSUN2/IGF2BP2/HMGA2 complex stabilizes HMGA2 to promote colorectal liver *** discoveries not only expand our understanding of circRNAs biology in tumor,but also demonstrate that m6A modification plays a key role for circRNAs in RNA ***,these findings indicate that circRNAs may be a new approach for therapeutic target of cancers.

关键词： CircRNAs Colorectal carcinoma IGF2BP2 Metastasis N6-methyladenosine

Genome-wide identification and characterization of odorant-binding protein （OBP） genes in the malaria vector Anopheles sinensis （Diptera： Culicidae）

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Insect Science 2016年第3期23卷 366-376页

作者： Xiu he Zheng-Bo he Yu-Juan zhang Yong Zhou Peng-Jie xian Liang Qiao Bin Chen Institute of Entomology and Molecular Biology College of Life Sciences Chongqing Normal University Chongqing 401331 China

Anopheles sinensis is a major malaria vector. Insect odorant-binding proteins （OBPs） may function in the reception of odorants in the olfactory system. The classification and characterization of the An. sinensis OBP genes have not been systematically studied. In this study, 64 putative OBP genes were identified at the whole-genome level of An. sinensis based on the comparison between OBP conserved motifs, PBP_GOBE and phylogenetic analysis with An. gambiae OBPs. The characterization of An. sinensis OBPs, including the motifs conservation, gene structure, genomic organization and classification, were investigated. A new gene, AsOBP73, belonging to the Plus-C subfamily, was identified with the support of transcript and conservative motifs. These An. sinensis OBP genes were classified into three subfamilies with 37, 15 and 12 genes in the subfamily Classic, Atypical and Plus-C, respectively. The genomic organization of An. sinensis OBPs suggests a clustered distribution across nine different scaffolds. Eight genes （0BP23-28, 0BP63- 64） might originate from a single gene through a series of historic duplication events at least before divergence of Anopheles, Culex and Aedes. The microsynteny analyses indicate a very high synteny between An. sinensis and An. gambiae OBPs. OBP70 and OBP71 earlier classified under Plus-C in An. gambiae are recognized as belonging to the group Obp59a of the Classic subfamily, and OBP69 earlier classified under Plus-C has been moved to the Atypical subfamily in this study. The study established a basic information frame for further study of the OBP genes in insects as well as in An. sinensis.

关键词： Anopheles sinensis characterization classification genome-wide identifi-cation OBPs phylogenetics

Photo Switchable Two-step Photochromism in a Series of Ln-Phosphonate(Ln=Dy,Gd,Tb,Y)Dinuclear Complexes

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Chemical Research in Chinese Universities 2022年第1期38卷 58-66页

作者： HU Ji-xiang zhang Qian XIA Bin LIU Tao PANG Jiandong BU xian-he School of Materials Science and Engineering Nankai UniversityTianjin 300350P.R.China College of Chemistry and Chemical Engineering Qingdao UniversityShandong 266071P.R.China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024P.R.China

Exploring the discrete complexes with multi-step coloration is still a challenge in the field of electron transfer photochromic materials. herein, we synthesized a series of dinuclear Ln-diphosphonate compounds[Ln=Dy(1);Gd(2);Tb(3);Y(4)] with a remarkably and reversibly photoactive coloration phenomenon. These compounds showed two-step coloration behavior, which were the first discrete architectures in the reported electron transfer photochromic complexes. This two-step coloration phenomenon was originated from the large distortion of H3-TPT acceptors, which in turn reduced the π-conjugation of electron acceptors and slowed the decay process of electron transfer. The photogenerated stable doublet radicals originated from electron transfer from diphosphonate donor to polypyridine acceptor in these complexes were detected by UV-Vis and electron spin resonance(ESR) spectra. Furthermore, the photogenerated radicals were estimated by direct current magnetic susceptibilities and variable temperature ESR spectra, suggesting the doublet radicals in the dinuclear structure for all the compounds. This work revealed a series of discrete phosphonate-based systems with a multi-step coloration process, providing a new pathway for designing multicolor photochromic materials with potential photoswitching or other applications.

关键词： Discrete structure Donor-acceptor system Doublet radical Photomagnetism Two-step photochromism

Predicting the elemental compositions of solid waste using ATR-FTIR and machine learning

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Frontiers of Environmental Science & Engineering 2023年第10期17卷 41-54页

作者： Haoyang xian Pinjing he Dongying Lan Yaping Qi Ruiheng Wang Fan Lü Hua zhang Jisheng Long Institute of Waste Treatment&Reclamation College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization Shanghai 200092China Shanghai SUS Environment Co. Ltd.Shanghai 201703China

Elemental composition is a key parameter in solid waste treatment and disposal. This study has proposed a method based on infrared spectroscopy and machine learning algorithms that can rapidly predict the elemental composition (C, H, N, S) of solid waste. Both noise and moisture spectral interference that may occur in practical application are investigated. By comparing two feature selection methods and five machine learning algorithms, the most suitable models are selected. Moreover, the impacts of noise and moisture on the models are discussed, with paper, plastic, textiles, wood, and leather as examples of recyclable waste components. The results show that the combination of the feature selection and K-nearest neighbor (KNN) approaches exhibits the best prediction performance and generalization ability. Particularly, the coefficient of determination (R2) of the validation set, cross validation and test set are higher than 0.93, 0.89, and 0.97 for predicting the C, H, and N contents, respectively. Further, KNN is less sensitive to noise. Under moisture interference, the combination of feature selection and support vector regression or partial least-squares regression shows satisfactory results. Therefore, the elemental compositions of solid waste are quickly and accurately predicted under noise and moisture disturbances using infrared spectroscopy and machine learning algorithms.

关键词： Elemental composition Infrared spectroscopy Machine learning Moisture interference Solid waste Spectral noise

Drought-induced proline is mainly synthesized in leaves and transported to roots in watermelon under water deficit

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Horticultural Plant Journal 2022年第5期8卷 615-626页

作者： Zhongyuan Wang Yongchao Yang Vivek Yadav Wei Zhao Yaping he xian zhang Chunhua Wei College of Horticulture State Key Laboratory of Crop Stress Biology in Arid AreasNorthwest A&F UniversityYangling 712100ShaanxiChina College of Biological and Agricultural Sciences Honghe UniversityMengzi 661100YunnanChina State Key Laboratory of Vegetable Germplasm Innovation Tianjin Kernel Agricultural Corporation LtdTianjin 300384China

Proline accumulation has been shown to occur in plants in response to various environmental *** proline metabolismrelated genes have been functionally characterized,the inter-organ transport of proline in stressed plants remains *** this study,free proline was detected with significant accumulations in the roots,stems,and leaves of watermelon drought-tolerant germplasm M08 and drought-susceptible line Y34 under drought *** profiling and enzyme activity measurements revealed that ClP5CS1 gene,rather than its paralog ClP5CS2,mainly contributes to the proline synthesis in leaves via the Glu ***,over-expression of the ClP5CS genes significantly enhanced the drought tolerance of transgenic Arabidopsis ***,we confirmed that proline is mainly synthesized in leaves and transported to roots in watermelon under drought *** and expression analyses revealed that the genes involved in proline metabolism exhibited different expression ***,ClP5CS1 was upregulated in leaves and roots,while ClP5CS2 was downregulated under drought ***,415 and 362 differently expressed TFs were identified in roots and leaves,respectively,with the majority upregulated in the ***,a model for proline metabolism was *** findings of this study provided new insights into the biosynthesis,transport,and regulatory mechanism of drought-induced proline in plants.

关键词： Watermelon Drought stress Proline Inter-organ transport

Flotation separation of spodumene and albite with activation of calcium ion hydrolysate components

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Rare Metals 2022年第11期41卷 3919-3931页

作者： xian-Ping Luo Yong-Bing zhang he-Peng Zhou Fan-Xin Xie Zhi-Zhao Yang Bo-Yuan zhang Cai-Gui Luo Engineering Research Center for High-Efficiency Development and Application Technology of Tungsten Resources(Jiangxi University of Science and Technology) Ministry of EducationGanzhou341000China Jiangxi Province Key Laboratory of Mining and Metallurgy Environmental Pollution Control Jiangxi University of Science and TechnologyGanzhou341000China

It is difficult to separate spodumene and albite by flotation with calcium ion as *** this study,microflotation experiment,solution chemistry calculation,density functional theory(DFT)calculation and X-ray photoelectron spectroscopy(XPS)analysis were conducted to investigate the effect mechanism of c alcium hydrolysate on the flotation separation of spodumene and *** show that the weak interaction intensity of Ca^(2+)with O atoms on the mineral surface makes it difficult to activate minerals *** O atom in the hydroxyl group of Ca(OH)^(+)and Ca(OH)_(2)can be strongly bonded with Al atom on the mineral surface,which greatly improves the adsorption *** the activation of Ca(OH)^(+),the adsorption forms of collectors on the surface of spodumene and albite are quite different,and the adsorption intensity on the surface of spodumene is higher,which is conducive to the flotation separation of spodumene and *** the action of Ca(OH)_(2),the adsorption of the collector on the albite surface is stronger than that of spodumene,which is not conducive to the flotation separation of the two *** adjusting the initial concentration of calcium ions and pulp pH,Ca(OH)^(+)is the main active component,which is the key to improve the separation effect of spodumene and albite.

关键词： Spodumene Albite Calcium ions Hydrolysate components Flotation Separation

Effectively enhancing recovery of fine spodumene via aggregation flotation

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Rare Metals 2020年第3期39卷 316-326页

作者： he-Peng Zhou Jie Hu Yong-Bing zhang Yi-Jun Cao xian-Ping Luo Xue-Kun Tang School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou221116China Faculty of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China Chinese National Engineering Research Center of Coal Preparation and Purification China University of Mining and TechnologyXuzhou221116China henan Province Industrial Technology Research Institute of Resources and Materials Zhengzhou UniversityZhengzhou450001China Western Mining Co. Ltd.Xining810006China

The effects of shear strength on aggregation flotation processes for fine spodumene(particle size less than 19μm)were investigated in this *** oleate was used as a surfactant and *** shear strength was controlled by varying the agitation speed of a selfmade stirring *** aggregation process was studied by measuring the continuous transformations in the size distribution and shape of *** results showed that as the shear strength increased,the distribution of fine spodumene transformed from bimodal to unimodal *** flocs tended to bridge more branches with a high shear strength and form globule-like flocs with very high *** parameter"aggregation degree"was introduced to evaluate the aggregation process as a function of shear *** flotation rate of flocs formed with different shear strengths was also *** results demonstrated that the flotation rate was closely related to shear strength and that there was a close correlation between this and aggregation *** results could be used to guide the actual production of fine particles via shear aggregation flotation.

关键词： Shear strength Fine spodumene Flotation rate Shear aggregation Sodium oleate

Complex structure of human Hsp90~N and a novel small inhibitor FS5

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Nuclear Science and Techniques 2020年第3期31卷 74-84页

作者： Rui Liu Xiao-Lu Lu xian-Hua Huang Wei he Jing-Jing Duan Jin zhang Jian Li School of Basic Medical Sciences Nanchang UniversityNanchang 330031China College of Pharmaceutical Sciences Gannan Medical UniversityGanzhou 341000China Human Aging Research Institute(HARI) School of Life SciencesNanchang UniversityNanchang 330031China Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases Ministry of EducationGannan Medical UniversityGanzhou 341000China

heat shock proteins(Hsps)are a family of abundantly expressed ATP-dependent chaperone ***90 is an eminent member of Hsp *** far,two primary functions have been described for Hsp90:first,as a regulator of conformational change of some protein kinases and nuclear hormone receptors,and the other as an indispensable factor in cellular stress ***90 has an essential number of interaction proteins since it participates in almost every biological process and its importance is ***90 has an inextricable relationship in the pathogenesis of cancer,especially in the proliferation and irradiation of cancer cells,thus being a notable cancer *** the discovery of geldanamycin,the first inhibitor of Hsp90,from the bacterial species Streptomyces hygroscopicus,even more attention has been focused toward *** structure-based inhibitors of Hsp90 have been designed to develop an innovative method to defeat ***,already designed inhibitors have various deficiencies,such as hepatotoxicity,poor aqueous solubility,instability,and non-ideal oral *** on the aforementioned reasons and to achieve an optimal performance and fewer side effects,we designed a novel inhibitor of Hsp90,called FS5,and resolved the crystal structure of the Hsp90^N-FS5 complex(1.65 A°,PDB code 5XRB).Furthermore,we compared the complexes Hsp90^N,Hsp90^N-GDM,and Hsp90^N-ATP and suggest that the inhibitor FS5 may compete with ATP for binding to Hsp90,which can be regarded as a potential strategy for the development of novel cancer drugs in the future.

关键词： heat shock protein 90 Complex crystal structure Interactions Anti-tumor drugs X-ray diffraction

The study of a neutron spectrum unfolding method based on particle swarm optimization combined with maximum likelihood expectation maximization

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Nuclear Science and Techniques 2023年第4期34卷 149-160页

作者： Hong-Fei Xiao Qing-xian zhang he-Yi Tan Bin Shi Jun Chen Zhi-Qiang Cheng Jian zhang Rui Yang Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of TechnologyChengdu 610059China National Key Laboratory for Metrology and Calibration Techniques China Institute of Atomic EnergyBeijing 102413China

The neutron spectrum unfolding by Bonner sphere spectrometer(BSS) is considered a complex multidimensional model,which requires complex mathematical methods to solve the first kind of Fredholm integral equation. In order to solve the problem of the maximum likelihood expectation maximization(MLEM) algorithm which is easy to suffer the pitfalls of local optima and the particle swarm optimization(PSO) algorithm which is easy to get unreasonable flight direction and step length of particles, which leads to the invalid iteration and affect efficiency and accuracy, an improved PSO-MLEM algorithm, combined of PSO and MLEM algorithm, is proposed for neutron spectrum unfolding. The dynamic acceleration factor is used to balance the ability of global and local search, and improves the convergence speed and accuracy of the algorithm. Firstly, the Monte Carlo method was used to simulated the BSS to obtain the response function and count rates of BSS. In the simulation of count rate, four reference spectra from the IAEA Technical Report Series No. 403 were used as input parameters of the Monte Carlo method. The PSO-MLEM algorithm was used to unfold the neutron spectrum of the simulated data and was verified by the difference of the unfolded spectrum to the reference spectrum. Finally, the 252Cf neutron source was measured by BSS, and the PSO-MLEM algorithm was used to unfold the experimental neutron *** with maximum entropy deconvolution(MAXED), PSO and MLEM algorithm, the PSO-MLEM algorithm has fewer parameters and automatically adjusts the dynamic acceleration factor to solve the problem of local optima. The convergence speed of the PSO-MLEM algorithm is 1.4 times and 3.1 times that of the MLEM and PSO algorithms. Compared with PSO, MLEM and MAXED, the correlation coefficients of PSO-MLEM algorithm are increased by 33.1%, 33.5% and 1.9%, and the relative mean errors are decreased by 98.2%, 97.8% and 67.4%.

关键词： Particle swarm optimization Maximum likelihood expectation maximization Neutron spectrum unfolding Bonner spheres spectrometer Monte Carlo method