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胃底腺型肿瘤的内镜与病理学分析
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作者 陈建华 施宏 +3 位作者 陈素玉 黄瑞 林丽琳 张宇 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第15期764-768,共5页
目的探讨胃底腺型肿瘤胃泌酸腺腺瘤(oxyutic gland adenoma,OGA)和胃底腺腺癌(gastric adenocarcinoma of fundic gland type,GA-FG)的临床病理特征。方法回顾性分析2020年8月至2023年2月福建省肿瘤医院收治的6例胃底腺型肿瘤患者,分析... 目的探讨胃底腺型肿瘤胃泌酸腺腺瘤(oxyutic gland adenoma,OGA)和胃底腺腺癌(gastric adenocarcinoma of fundic gland type,GA-FG)的临床病理特征。方法回顾性分析2020年8月至2023年2月福建省肿瘤医院收治的6例胃底腺型肿瘤患者,分析其临床资料、内镜学特征、病理特征、免疫组织化学结果,治疗及预后情况。结果6例患者中男性1例,女性5例,平均年龄57岁。主要发生部位为胃底、胃体,以浅表隆起型多见。病理形态特点为胃底腺型肿瘤大多位于胃黏膜深层,表现为腺体结构紊乱,主要由主细胞型细胞构成。其中OGA 3例,GA-FG 3例。免疫组织化学表达结果为胃蛋白酶原重组人抗体1(pepsinogen 1)阳性5例,MUC65例,突触素(synaptophysin,Syn)阳性6例,嗜铬蛋白(chromogranin,CgA)均为阴性,肿瘤增殖标记物(Ki-67)<10%。结论OGA与GA-FG发病率低,无明显的内镜学特异性,如内镜医师认识不足,易误诊漏诊;免疫组织化学有助于鉴别诊断,首选内镜下黏膜切除或者剥离术治疗。 展开更多
关键词 胃泌酸腺腺瘤 胃底腺腺癌 MUC6 内镜下黏膜下剥离术
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A Case Study Applying Mesoscience to Deep Learning
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作者 Li Guo Fanyong Meng +4 位作者 Pengfei Qin Zhaojie Xia Qi Chang jianhua chen Jinghai Li 《Engineering》 SCIE EI CAS CSCD 2024年第8期84-93,共10页
In this paper,we propose mesoscience-guided deep learning(MGDL),a deep learning modeling approach guided by mesoscience,to study complex systems.When establishing sample dataset based on the same system evolution data... In this paper,we propose mesoscience-guided deep learning(MGDL),a deep learning modeling approach guided by mesoscience,to study complex systems.When establishing sample dataset based on the same system evolution data,different from the operation of conventional deep learning method,MGDL introduces the treatment of the dominant mechanisms of complex system and interactions between them according to the principle of compromise in competition(CIC)in mesoscience.Mesoscience constraints are then integrated into the loss function to guide the deep learning training.Two methods are proposed for the addition of mesoscience constraints.The physical interpretability of the model-training process is improved by MGDL because guidance and constraints based on physical principles are provided.MGDL was evaluated using a bubbling bed modeling case and compared with traditional techniques.With a much smaller training dataset,the results indicate that mesoscience-constraint-based model training has distinct advantages in terms of convergence stability and prediction accuracy,and it can be widely applied to various neural network configurations.The MGDL approach proposed in this paper is a novel method for utilizing the physical background information during deep learning model training.Further exploration of MGDL will be continued in the future. 展开更多
关键词 Mesoscience Deep learning Complex system Gas-solid system Bubbling bed
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Impact of ethanol on the flotation efficiency of imidazolium ionic liquids as collectors:Insights from dynamic surface tension and solvation analysis
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作者 Qian cheng Zerui Lei +1 位作者 Guangjun Mei jianhua chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2645-2656,共12页
To conduct extensive research on the application of ionic liquids as collectors in mineral flotation,ethanol(EtOH)was used as a solvent to dissolve hydrophobic ionic liquids(ILs)to simplify the reagent regime.Interest... To conduct extensive research on the application of ionic liquids as collectors in mineral flotation,ethanol(EtOH)was used as a solvent to dissolve hydrophobic ionic liquids(ILs)to simplify the reagent regime.Interesting phenomena were observed in which EtOH exerted different effects on the flotation efficiency of two ILs with similar structures.When EtOH was used to dissolve 1-dodecyl-3-methylimidazolium chloride(C12[mim]Cl)and as a collector for pure quartz flotation tests at a concentration of 1×10^(−5)mol·L^(−1),quartz recovery increased from 23.77%to 77.91%compared with ILs dissolved in water.However,quartz recovery of 1-dodecyl-3-methylim-idazolium hexafluorophosphate(C12[mim]PF6)decreased from 60.45%to 24.52%under the same conditions.The conditional experi-ments under 1×10^(−5)mol·L^(−1)ILs for EtOH concentration and under 2vol%EtOH for ILs concentration confirmed this difference.After being affected by EtOH,the mixed ore flotation tests of quartz and hematite showed a decrease in the hematite concentrate grade and re-covery for the C12[mim]Cl collector,whereas the hematite concentrate grade and recovery for the C12[mim]PF6 collector increased.On the basis of these differences and observations of flotation foam,two-phase bubble observation tests were carried out.The EtOH promoted the foam height of two ILs during aeration.It accelerated static froth defoaming after aeration stopped,and the foam of C12[mim]PF6 de-foaming especially quickly.In the discussion of flotation tests and foam observation,an attempt was made to explain the reasons and mechanisms behind the diverse phenomena using the dynamic surface tension effect and solvation effect results from EtOH.The solva-tion effect was verified through Fourier transform infrared(FT-IR),X-ray photoelectron spectroscopy(XPS),and Zeta potential tests.Al-though EtOH affects the adsorption of ILs on the ore surface during flotation negatively,it holds an positive value of inhibiting foam mer-ging during flotation aeration and accelerating the defoaming of static foam.And induce more robust secondary enrichment in the mixed ore flotation of the C12[mim]PF6 collector,facilitating effective mixed ore separation even under inhibitor-free conditions. 展开更多
关键词 ionic liquid ETHANOL flotation foam SOLVATION dynamic surface tension
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π-Extended giant dimeric acceptor as a third component enables highly efficient ternary organic solar cells with efficiency over 19.2%
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作者 Mengran Peng Haotian Wu +7 位作者 Liming Wu jianhua chen Ruijie Ma Qunping Fan Hua Tan Weiguo Zhu Hongxiang Li Junqiao Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期263-270,I0006,共9页
Ternary strategy with a suitable third component is a successful strategy to improve the photovoltaic performance of organic solar cells(OSCs).Very recently,Y-series based giant molecule acceptors or oligomerized acce... Ternary strategy with a suitable third component is a successful strategy to improve the photovoltaic performance of organic solar cells(OSCs).Very recently,Y-series based giant molecule acceptors or oligomerized acceptors have emerged as promising materials for achieving highly efficient and stable binary OSCs,while application as third component for ternary OSCs is limited.Here a novelπ-extended giant dimeric acceptor,GDF,is developed based on central Y series core fusion and rigid BDT as linker,and then incorporated into the state-of-the-art PM1:PC6 system to construct ternary OSCs.The GDF has a near planar backbone,resulting in increasedπ-conjugation,excellent crystallinity,and good electron transport capacity.When GDF is introduced into the PM1:PC6 system,it ensues in a cascade like the lowest unoccupied molecular orbitals(LUMO)energy level alignment,a complementary absorption band with PM1 and PC6,higher and balanced hole and electron mobility,slightly smaller domain size,and a higher exciton dissociation probability for PM1:PC6:GDF(1:1.1:0.1)blend film.As a consequence,the PM1:PC6:GDF(1:1.1:0.1)ternary OSC achieves a champion PCE of 19.22%,with a significantly higher open-circuit voltage and short-circuit current density,compared to 18.45%for the PM1:PC6(1:1.2)binary OSC.Our findings show that employing aπ-extended giant dimeric acceptor as a third component significantly improves the photovoltaic performance of ternary OSCs. 展开更多
关键词 Giant dimeric acceptor Third component Ternary organic solar cells
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Indacenodithiophene-based single-component ambipolar polymer for high-performance vertical organic electrochemical transistors and inverters
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作者 Yimin Sun Yu Lan +9 位作者 Meisi Li Wang Feng Miao Xie Yueping Lai Wei Li Yuhua cheng jianhua chen Wei Huang Liang-Wen Feng Junqiao Ding 《Aggregate》 EI CAS 2024年第5期297-306,共10页
Single-component ambipolar polymers are highly desirable for organic electrochem-ical transistors(OECTs)and integration into complementary logic circuits with reduced process complexity.However,they often suffer from ... Single-component ambipolar polymers are highly desirable for organic electrochem-ical transistors(OECTs)and integration into complementary logic circuits with reduced process complexity.However,they often suffer from imbalanced p-type and n-type characteristics and/or stability issues.Herein,a novel single-component ambipolar polymer,namely,gIDT–BBT is reported based on indacenodithiophene(IDT)as the electron donor,benzobisthiadiazole(BBT)as the electron acceptor and oligo ethylene glycol(OEG)as the side chain.Benefitting from the extended backbone planarity and rigidity of IDT,pronounced electron-withdrawing capabil-ity of BBT,favored ionic transport from OEG together with vertical OECT device structure,a nearly balanced ambipolar OECT performance is achieved for gIDT–BBT,revealing a high transconductance of 155.05±1.58/27.28±0.92 mS,a high current on/off ratio>10^(6) and an excellent operational stability under both p-type and n-type operation conditions.With gIDT–BBT in hand,furthermore,vertically stacked complementary inverters are successfully fabricated to show a maximum voltage gain of 28 V V^(-1)(V_(IN)=0.9 V)and stable operation over 1000 switching cycles,and then used for efficient electrooculogram recording.This work provides a new approach for the development of ambipolar single-component organic mixed ionic–electronic conductors and establishes a foundation for the manufacture of high-performance ambipolar OECTs and associated complementary circuits. 展开更多
关键词 electrooculogram recording INVERTERS single-component ambipolar polymer vertical organic electro-chemical transistors
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Technique of Earthworms Restoring Soil in Greenhouse Cultivation
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作者 Yanjiao LI Jiafei SU +7 位作者 Zhiu ZHANG Guang QI jianhua chen Lixuan KOU Limin WANG Wenxian LIU Junyi ZHANG Libing QIU 《Asian Agricultural Research》 2024年第1期40-43,共4页
The production environment of greenhouse cultivation is relatively closed,the multiple cropping index is high,the management of fertilizationwatering and pesticideapplication isblindtosomeextent,andthe phenomenonofcon... The production environment of greenhouse cultivation is relatively closed,the multiple cropping index is high,the management of fertilizationwatering and pesticideapplication isblindtosomeextent,andthe phenomenonofcontinuous cropping isalsocommonSoilquali-ty affects the sustainable development of greenhouse cultivation.Earthworm is a ubiquitous invertebrate organism in soil,an important part of soil system,a link between terrestrial organisms and soil organisms,an important link in the small cycle of soil material organisms,and plays an important role in maintaining the structure and function of soil ecosystem.Different ecotypes of earthworms are closely related to their habi-tats(soil layers)and food resource preferences,and then affect their ecological functions.The principle of earthworm regulating soil function is essentially the close connection and interaction between earthworm and soil microorganism.Using different ecotypes of earthworms and bio-logical agents to carry out combined remediation of greenhouse cultivation soil is a technical model to realize sustainable development of green-house cultivation. 展开更多
关键词 Earthworms Greenhouse cultivation Soil remediation Biological agent
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First-principles study on the co-adsorption of water and oxygen molecules on chalcopyrite(112)-M surface 被引量:1
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作者 Yingchao Liu jianhua chen +1 位作者 Yuqiong Li Cuihua Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第8期1055-1063,共9页
Chalcopyrite is a common copper-bearing mineral with antiferromagnetic properties.However,this property has rarely been considered in previous studies for detailed adsorption behaviors of molecules on chalcopyrite.Bas... Chalcopyrite is a common copper-bearing mineral with antiferromagnetic properties.However,this property has rarely been considered in previous studies for detailed adsorption behaviors of molecules on chalcopyrite.Based on density functional theory(DFT),new adsorption pathways by H_(2)O and O_(2)on the chalcopyrite metal terminated(112)surface((112)-M)is found in this work.First,through simulating the adsorption of an isolated water molecule and monolayer water molecules,it is confirmed that H_(2)O molecules tend to adsorb on the surface Fe atoms more than on the surface Cu atoms.Then,we studied various adsorption behaviors of the O_(2)molecule.It is found that the adsorption on the hollow FeAFe site is the most stable case;however,O_(2)is undissociated.Two adsorption cases will happen when H_(2)OAO_(2)adsorb simultaneously on the surface.For the S site,the H_(2)O molecule thoroughly dissociated and formed SAO species,and the other case is H_(2)O undissociated adsorbing at the Cu site.For the former case,it is interesting that H_(2)O is dissociated before O_(2). 展开更多
关键词 CHALCOPYRITE Water molecule Oxygen molecule CO-ADSORPTION
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Effect of content and spin state of iron on electronic properties and floatability of iron-bearing sphalerite:A DFT+U study
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作者 Yao Feng Zhuofan Li +1 位作者 jianhua chen Ye chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第12期1563-1571,共9页
Iron is an impurity widely occurred in sphalerite,and its effect on sphalerite flotation is complex.In this work,the effects of iron content and spin state on electronic properties and floatability of iron-bearing sph... Iron is an impurity widely occurred in sphalerite,and its effect on sphalerite flotation is complex.In this work,the effects of iron content and spin state on electronic properties and floatability of iron-bearing sphalerite are comprehensively studied using density functional theory Hubbard U(DFT+U)calculations combined with coordination chemistry flotation.The band gap of ideal sphalerite is 3.723 eV,and thus electron transition is difficult to occur,resulting in poor floatability.The results suggest the band gap of sphalerite decreases with increasing iron content.For low iron content,the decreased band gap facilitates electron transition;at this case,Fe^(2+)in a high-spin state possesses oneπelectron pair,which can form a weakπ-backbonding with xanthate,causing increasing floatability.However,for medium and high iron-bearing sphalerite,with the further decrease of band gap,Fe^(2+)is oxidized to Fe^(3+)due to electrochemical interaction,and henceπ-backbonding is eliminated,leading to lower floatability of iron-bearing sphalerite,which is consistent with the flotation experimental results.This work could give a deeper understanding of how sphalerite flotation behaviors are affected by iron content. 展开更多
关键词 SPHALERITE Iron-bearing sphalerite Iron content Spin state Density functional theory
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π-Extension and chlorination of non-fullerene acceptors enable more readily processable and sustainable high-performance organic solar cells
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作者 Ning Su jianhua chen +6 位作者 Mengran Peng Guoping Li Robert M.Pankow Ding Zheng Junqiao Ding Antonio Facchetti Tobin J.Marks 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期321-329,共9页
Organic solar cells(OSCs)processed without halogenated solvents and complex treatments are essential for future commercialization.Herein,we report three novel small molecule acceptors(NFAs)consisting of a Y6-like core... Organic solar cells(OSCs)processed without halogenated solvents and complex treatments are essential for future commercialization.Herein,we report three novel small molecule acceptors(NFAs)consisting of a Y6-like core but withπ-extended naphthalene with progressively more chlorinated end-capping groups and a longer branched chain on the Nitrogen atom.These NFAs exhibit good solubilities in nonchlorinated organic solvents,broad optical absorptions,closeπ-πstacking distances(3.63–3.84A),and high electron mobilities(~10^(-3)cm^(2)V^(-1)s^(-1)).The o-xylene processed and as-cast binary devices using PM6 as the donor polymer exhibit a PCE increasing upon progressive chlorination of the naphthalene end-capping group from 8.93%for YN to 14.38%for YN-Cl to 15.00%for YN-2Cl.Furthermore similarly processed ternary OSCs were fabricated by employing YN-Cl and YN-2Cl as the third component of PM6:CH1007 blends(PCE=15.75%).Compared to all binary devices,the ternary PM6:CH1007:YN-Cl(1:1:0.2)and PM6:CH1007:YN-2Cl(1:1:0.2)cells exhibit significantly improved PCEs of 16.49%and15.88%,respectively,which are among the highest values reported to date for non-halogenated solvent processed OSCs without using any additives and blend post-deposition treatments. 展开更多
关键词 Non-fullerene acceptors Non-chlorinated organic solvents Organic solar cells
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Stretchable organic electrochemical transistors with micro-/nano-structures
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作者 jianhua chen Yiming Sun +2 位作者 Jie Sun Junqiao Ding Liming Ding 《Journal of Semiconductors》 EI CAS CSCD 2023年第12期1-3,共3页
Organic electrochemical transistors(OECTs)have attracted attention due to their unique function of converting ionic and biological signals into electronic signals,high transconductance,low energy consumption(below 1 V... Organic electrochemical transistors(OECTs)have attracted attention due to their unique function of converting ionic and biological signals into electronic signals,high transconductance,low energy consumption(below 1 V),stable operation in aqueous media,good biocompatibility[1,2].However,most OECTs are usually built on brittle and stiff substrates,and inappropriate to be adhered to or contacted with delicate human skin,thus impeding their use in wearable electronics.It is desirable to exploit stretchable OECTs to reduce the mechanical mismatch with soft tissues. 展开更多
关键词 TRANSISTORS ELECTROCHEMICAL STIFF
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注气与注水肠镜下结直肠息肉的内镜形态与病理关系的比较 被引量:14
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作者 陈建华 施宏 +1 位作者 陈素玉 黄瑞 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第5期236-240,共5页
目的:比较注气与注水结肠镜下结直肠息肉的内镜形态特征与病理类型之间的关系。方法:选取2018年9月至2019年6月于福建省肿瘤医院在非放大内镜窄带成像(narrow-band imaging,NBI)模式下62例接受注气肠镜与53例注水肠镜检查发现的结直肠... 目的:比较注气与注水结肠镜下结直肠息肉的内镜形态特征与病理类型之间的关系。方法:选取2018年9月至2019年6月于福建省肿瘤医院在非放大内镜窄带成像(narrow-band imaging,NBI)模式下62例接受注气肠镜与53例注水肠镜检查发现的结直肠息肉进行观察,分析病变的血管形态及表面的结构,应用国际结直肠内镜分型(NICE)实时预测病理类型,并将NBI内镜诊断结果与病理组织学诊断结果进行分析,比较两组的敏感度、特异度、准确率以及扁平息肉(即巴黎分型0~Ⅱa型)的检出率。结果:注水组扁平状息肉检出率为44.64%,其中左半、右半结肠检出率分别为26.78%、17.86%;注气组为40.00%,左半、右半结肠检出率分别35.56%、4.44%;两组检查结果差异具有统计学意义(P<0.01)。NICE分型实时预测结直肠息肉病变总的敏感度、特异度、准确率分别为91.95%、96.61%、93.84%,其中注气组的分别为90.74%、97.27%、93.33%,注水组的分别为93.93%、95.65%、94.64%,并发现2例无蒂锯齿状腺瘤(sessile serrated adenoma,SSA),两组检查结果差异无统计学意义。结论:注气肠镜与注水肠镜预测结直肠息肉的病理类型准确性无显著性差异,但注水肠镜能提高右半结肠0~Ⅱa型息肉的检出。 展开更多
关键词 内镜窄带成像 NICE分型 结直肠息肉
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Adsorption removal of o-nitrophenol and p-nitrophenol from wastewater by metal–organic framework Cr-BDC 被引量:7
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作者 jianhua chen Xue Sun +2 位作者 Lijing Lin Xinfei Dong Yasan He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第6期775-781,共7页
In the present paper, a metal–organic framework Cr-BDC was prepared and used as adsorbent for adsorption of o-nitrophenol(ONP) and p-nitrophenol(PNP) from aqueous solutions. Cr-BDC was characterized by scanning elect... In the present paper, a metal–organic framework Cr-BDC was prepared and used as adsorbent for adsorption of o-nitrophenol(ONP) and p-nitrophenol(PNP) from aqueous solutions. Cr-BDC was characterized by scanning electron microscopy, transmission electron microscope, X-ray diffraction and BET methods. The results indicate that Cr-BDC gets a very large specific surface area of 4128 m^2·g^(-1)and pore sizes are concentrated in 1 nm, which is a benefit for using for wastewater treatment. The influences of the adsorption conditions, such as temperature,solution concentration, adsorption time and reusability on adsorption performance were investigated. Cr-BDC exhibited an encouraging uptake capacity of 310.0 mg·g^(-1)for ONP, and adsorption capacity of Cr-BDC for ONP is significantly higher than that for PNP under suitable adsorption conditions. The characterizations of adsorption process were examined with the Lagergren pseudo-first-order, the pseudo-second-order kinetic model, and the intra-particular diffusion model. Kinetics experiments indicated that the pseudo-second-order model displayed the best correlation with adsorption kinetics data. Furthermore, our adsorption equilibrium data could be better described by the Freundlich equation. The results indicate that the as-prepared Cr-BDC is promising for use as an effective and economical adsorbent for ONP removal. 展开更多
关键词 METAL-ORGANIC framework O-NITROPHENOL P-NITROPHENOL ISOMERS ADSORPTION
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Insight into mineral flotation fundamentals through the DFT method 被引量:7
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作者 Weiyong Cui jianhua chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第6期983-994,共12页
Flotation is a complex process that occurs in solid-liquid-gas multiphase systems,and its main factors include the minerals,separation medium,as well as various flotation reagents.The study of mineral properties and i... Flotation is a complex process that occurs in solid-liquid-gas multiphase systems,and its main factors include the minerals,separation medium,as well as various flotation reagents.The study of mineral properties and interactions with other components such as reagents and water lays the basic theoretical foundation for flotation.Density functional theory(DFT) calculations can qualitatively evaluate the exchange of matter and energy between the mineral system and the surroundings and quantitatively characterize these behaviors,which greatly expands the breadth and depth of flotation studies.This review systematically summarizes the advances of flotation research based on DFT studies,including the study of mineral crystal chemistry represented by the theory of lattice defects,mineral surface hydration such as hydrophilicity and hydrophobicity,surface regulation mechanism,and collecting mechanism based on surface adsorption theory.More significantly,it systematically elaborates different types of collectors according to their characteristics and emphatically explains the mechanism of some typical collectors in detail. 展开更多
关键词 Flotation fundamentals Adsorption behavior Crystal and surface Density functional theory
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Hydration mechanisms of smithsonite from DFT-D calculations and MD simulations 被引量:5
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作者 Yuanjia Luo Leming Ou +4 位作者 jianhua chen Guofan Zhang Yuqin Xia Bohan Zhu Hanyu Zhou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期605-613,共9页
Investigation on the mineralwater interactions is crucial for understanding the subsequent interfacial reactions.Currently,the hydration mechanisms of smithsonite are still obscure.In this paper,the adsorption of H_(2... Investigation on the mineralwater interactions is crucial for understanding the subsequent interfacial reactions.Currently,the hydration mechanisms of smithsonite are still obscure.In this paper,the adsorption of H_(2)O at different coverage rates on smithsonite(101)surface was innovatively investigated using density-functional theory(DFT)calculations and molecular dynamics(MD)simulations by analyzing adsorption model,interaction energy,atomic distance,density of state,electron density difference,concentration profile,radial distribution function and self-diffusion coefficient.We found that single H_(2)O preferred to be dissociated on smithsonite(101)surface via the interaction of surface Zn with the Ow of H_(2)O and H-bond between Hw of H_(2)O and surface Os.However,dissociation adsorption and molecular adsorption coexisted on the smithsonite surface at a high coverage rate of H_(2)O,and dissociation adsorption remained the main adsorption mechanism.Moreover,we found the interaction between smithsonite surface and H_(2)O was weakened as a function of H_(2)O coverage,which was because the presence of interlayer H_(2)O and different layers of H_(2)O decreased the reactivity of the smithsonite surface.The H_(2)O is mainly adsorbed on the smithsonite surface by forming three layers of H_(2)O(about 10–15Å),with the ordering degree gradually decreasing. 展开更多
关键词 H_(2)O Smithsonite surface DFT MD Coverage rate
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Water-oxygen interaction on marcasite(101)surface:DFT calculation 被引量:4
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作者 Junjie Zhang Yuqiong Li jianhua chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第1期191-199,共9页
Marcasite(FeS2)is widespread in nature,its oxidation plays a vital role in acid mine drainage,mineral resource recovery,and photoelectric material applications.In this paper,the oxidation mechanism of marcasite has be... Marcasite(FeS2)is widespread in nature,its oxidation plays a vital role in acid mine drainage,mineral resource recovery,and photoelectric material applications.In this paper,the oxidation mechanism of marcasite has been studied for the first time using density functional theory(DFT).It is found that,unlike the oxidation of pyrite,the oxidation of marcasite merely occurs at surface S atoms.Under the coexistence of water and oxygen,S atoms around surface Fe atoms are replaced by O atoms.The surface S sites are initially oxidized to form S==O bonds,and continue to adsorb oxygen to gradually generate SO3^2-,SO4^2-species,and eventually FeSO4.In this process,H2O molecules participate in neither oxidation nor dissociation,and they are adsorbed on surface Fe sites in the form of molecules,i.e.,all O atoms in SO4^2-derive from oxygen rather than water molecules. 展开更多
关键词 MARCASITE Surface oxidation ADSORPTION Density functional theory
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Insights into the adsorption performance and mechanism of hydrated Ca ion on talc(001) basal surface from DFT calculation 被引量:3
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作者 Yuanjia Luo Leming Ou +4 位作者 jianhua chen Guofan Zhang Yuqin Xia Bohan Zhu Hanyu Zhou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第4期887-896,共10页
The utilization of Ca ion as assistant depressant of CMC on talc has been widely reported.Thus,the study on the adsorption mechanism of Ca ion on talc surface is very crucial for understanding the performance of CMC o... The utilization of Ca ion as assistant depressant of CMC on talc has been widely reported.Thus,the study on the adsorption mechanism of Ca ion on talc surface is very crucial for understanding the performance of CMC on talc depression.In this paper,mechanism insights into hydrated Ca ion adsorption on talc(001) basal surface were creatively provided using DFT calculation.[Ca(H_(2)O)_6]^(2+) and [Ca(OH)(H_(2)O)_(3)]^(+) were determined as the effective hydrate components for Ca ion adsorption,and the top O site was the most favorable position for their adsorptions on talc surface.Furthermore,the adsorption mechanisms of [Ca(H_(2)O)_6]^(2+) and [Ca(OH)(H_(2)O)_(3)]^(+) on talc surface were found to be not the Ca-O chemical bond,but the hydrogen bonding formed by the H atom of the H_(2)O ligand and the surface O atom.H_(2)O acted like a bridge to connect them to the talc surface.Moreover,the hydrogen bonding was formed due to the hybridization of H 1s orbital with the O 2s,O 2p orbitals.Simultaneously,electrons transferred between the H atom and the surface O atom.This work provides theoretical insights into the Ca ion adsorption on talc surface,which can help deeply understand the talc flotation using CMC as depression. 展开更多
关键词 Ca ion Talc surface Adsorption DFT H_(2)O Bridge
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Knowledge of“Guidelines for the prevention of intravascular catheter-related infections(2011)”:A survey of intensive care unit nursing staffs in China 被引量:2
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作者 Shaolin chen Jun Yao +6 位作者 jianhua chen Lijuan Liu Aifeng Miu Yulan Jiang Jie Zhu Siyuan Tang Yuxiang chen 《International Journal of Nursing Sciences》 2015年第4期383-388,共6页
Aims and objectives:To evaluate intensive care unit(ICU)nurses'knowledge of the updated guidelines for the prevention of intravascular catheter-related infections;to identify the factors that affect the nurses'... Aims and objectives:To evaluate intensive care unit(ICU)nurses'knowledge of the updated guidelines for the prevention of intravascular catheter-related infections;to identify the factors that affect the nurses'knowledge and to explore the barriers to adherence to evidence-based guidelines in clinical practice in China.Methods:Cross-sectional surveys were carried out in Chinese ICUs from January 2013 to March 2014.The nurses'demographic information,knowledge of the guidelines,and barriers to adherence were assessed by a validated questionnaire and then analyzed statistically.Results:The questionnaires were completed by 455 ICU nurses from 4 provinces of China.The mean score was 8.17 of 20,and higher scores were significantly associated with province,years of experience,and years of ICU experience.Forty-nine(10.7%)nurses had not heard of the guidelines,whereas 231(50.7%)nurses heard of the guidelines but did not receive training for them.Trained nurses'scores were higher than untrained nurses'scores.The three main barriers to compliance with the guidelines were an unfamiliarity with them,an excessive workload due to a shortage of nurses,and a lack of training.Conclusions:ICU nurses'knowledge of the updated guidelines is quite low,which could be a potential risk factor for patient safety.Multidisciplinary interventions and continuous. 展开更多
关键词 GUIDELINES Evidence-based guidelines Intravascular catheter-related infections Nurses'knowledge Intensive care unit PREVENTION
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Quantifying growth and breakage of agglomerates in fluid-particle flow using discrete particle method 被引量:1
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作者 Lingfeng Zhou Junwu Wang +11 位作者 Wei Ge Shiwen Liu jianhua chen Ji xu Limin Wang Feiguo chen Ning Yang Rongtao Zhou Lin Zhang Qi Chang Philippe Ricoux Alvaro Fernandez 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期914-921,共8页
The cohesive solids in liquid flows are featured by the dynamic growth and breakage of agglomerates, and the difficulties in the development, design and optimization of these systems are related to this significant fe... The cohesive solids in liquid flows are featured by the dynamic growth and breakage of agglomerates, and the difficulties in the development, design and optimization of these systems are related to this significant feature.In this paper, discrete particle method is used to simulate a solid–liquid flow system including millions of cohesive particles, the growth rate and breakage rate of agglomerates are then systematically investigated. It was found that the most probable size of the agglomerates is determined by the balance of growth and breakage of the agglomerates the cross point of the lines of growth rate and breakage rate as a function of the particle numbers in an agglomerate, marks the most stable agglomerate size. The finding here provides a feasible way to quantify the dynamic behaviors of growth and breakage of agglomerates, and therefore offers the possibility of quantifying the effects of agglomerates on the hydrodynamics of fluid flows with cohesive particles. 展开更多
关键词 AGGLOMERATE Growth and breakage Quantification Discrete particle method
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Mineral Prospectivity Mapping Method Integrating Multi-Sources Geology Spatial Data Sets and Case-Based Reasoning 被引量:1
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作者 Binbin He jianhua chen +1 位作者 Cuihua chen Yue Liu 《Journal of Geographic Information System》 2012年第2期77-85,共9页
Extracting and synthesizing information from existing and massive amounts of geology spatial data sets is of great scientific significance and has considerable value in its applications. To make mineral exploration le... Extracting and synthesizing information from existing and massive amounts of geology spatial data sets is of great scientific significance and has considerable value in its applications. To make mineral exploration less expensive, more efficient, and more accurate, it is important to move beyond traditional concepts and establish a rapid, efficient, and intelligent method of predicting the existence and location of minerals. This paper describes a case-based reasoning (CBR) method for mineral prospectivity mapping that takes spatial features of geology data into account and offers an intelligent approach. This method include a metallogenic case representation that combines spatial and attribute features, metallogenic case-based storage organization, and a metallogenic case similarity retrieval model. The experiments were performed in the eastern Kunlun Mountains, China using CBR and weights-of-evidence (WOE), respectively. The results show that the prediction accuracy of the CBR is higher than that of the WOE. 展开更多
关键词 Mineral Prospectivity Mapping Case-Based Reasoning METALLOGENIC CASE Representation METALLOGENIC CASE Retrieval Eastern KUNLUN MOUNTAINS
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Value of partial hepatectomy for the treatment of hilar cholangiocarcinoma: a Meta-analysis study 被引量:1
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作者 Ming Yang Yanhong Zhang +2 位作者 Miaohang Cui jianhua chen JinLong Liu 《Oncology and Translational Medicine》 2019年第6期268-277,共10页
Objective To discuss the value of partial hepatectomy in patients with hilar cholangiocarcinoma.Methods English articles related to hilar cholangiocarcinoma were screened from January 1,1990 to May 12,2019 in the Pub ... Objective To discuss the value of partial hepatectomy in patients with hilar cholangiocarcinoma.Methods English articles related to hilar cholangiocarcinoma were screened from January 1,1990 to May 12,2019 in the Pub Med,MEDLINE,EMBASE,and Cochrane Library databases.Information on postoperative radical cure,survival,morbidity,and mortality after surgery were extracted from articles that met the inclusion criteria for the meta-analysis.Results Twenty-two articles that met the inclusion criteria were classified into 4 study groups: the hepatectomy radical cure group(19 articles),the hepatectomy survival group(16 articles),the hepatectomy morbidity group(9 articles),and the hepatectomy mortality group(17 articles).We found that the rate of radical cure after partial hepatectomy(odds ratio [OR] 0.32,95% confidence interval [CI] 0.20-0.51) and the survival rate(hazard ratio [HR] 0.67,95% CI 0.58-0.79) were significantly higher than after simple bile duct resection,but that morbidity(OR 1.99,95% CI 1.37-2.90) and mortality(OR 2.71,95% CI 1.47-4.98) in patients within the partial hepatectomy group were also higher than in the simple bile duct resection group,taking into account the significant heterogeneity in the articles pertaining to the hepatectomy radical cure group(I^2=68.3%,P=0.000),a sub-group analysis was subsequently conducted.Its results showed that when the branches of the secondary bile ducts were not involved during hilar cholangiocarcinoma,then a bile duct resection had a similar radical cure outcome as combined partial hepatectomy(OR 0.94,95% CI 0.54-1.65).Conclusion Partial hepatectomy can increase the proportion of radical cure in patients with hilar cholangiocarcinoma and extend the survival time after surgery.However,the morbidity and mortality after surgery are higher than those in simple bile duct resections.Therefore,simple bile duct resection is still a relevant and efficient tool in the treatment of Bismuth-Corlette Type Ⅰ and Ⅱ hilar cholangiocarcinomas. 展开更多
关键词 hilar cholangiocarcinoma partial hepatectomy PROGNOSIS META-ANALYSIS
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