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Configuring single-layer MXene nanosheet onto natural wood fiber via C-Ti-C covalent bonds for high-stability Li-S batteries
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作者 Yangyang Chen Yu Liao +5 位作者 Ying Wu Lei Li Zhen Zhang Sha Luo Yiqiang Wu Yan Qing 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期701-711,I0016,共12页
Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness.However,the low conductivity and ... Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness.However,the low conductivity and polysulfide shuttling effect of S cathodes severely hamper the practical performance of LSBs.Herein,in situ-generated single layer MXene nanosheet/hierarchical porous carbonized wood fiber(MX/PCWF)composites are prepared via a nonhazardous eutectic activation strategy coupled with pyrolysis-induced gas diffusion.The unique architecture,wherein single layer MXene nanosheets are constructed on carbonized wood fiber walls,ensures rapid polysulfide conversion and continuous electron transfer for redox reactions.The C-Ti-C bonds formed between MXene and PCWF can considerably expedite the conversion of polysulfides,effectively suppressing the shuttle effect.An impressive capacity of 1301.1 m A h g^(-1)at 0.5 C accompanied by remarkable stability is attained with the MX/PCWF host,as evidenced by the capacity maintenance of 722.6 m A h g^(-1)after 500 cycles.Notably,the MX/PCWF/S cathode can still deliver a high capacity of 886.8 m A h g^(-1)at a high S loading of 5.6 mg cm^(-2).The construction of two-dimensional MXenes on natural wood fiber walls offers a competitive edge over S-based cathode materials and demonstrates a novel strategy for developing high-performance batteries. 展开更多
关键词 Lithium-sulfur batteries S cathodes MXene nanosheets Wood fiber C-Ti-C bonds
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Design method of extractant for liquid-liquid extraction based on elements and chemical bonds
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作者 Yuwen Wei Chunling Zhang +4 位作者 Yue Zhang Lili Wang Li Xia Xiaoyan Sun Shuguang Xiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期193-202,共10页
In the petrochemical industry process, the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a common and e... In the petrochemical industry process, the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a common and effective separation method, and selecting an extraction agent is the key to extraction technology research. In this paper, a design method of extractants based on elements and chemical bonds was proposed. A knowledge-based molecular design method was adopted to pre-select elements and chemical bond groups. The molecules were automatically synthesized according to specific combination rules to avoid the problem of “combination explosion” of molecules. The target properties of the extractant were set, and the extractant meeting the requirements was selected by predicting the correlation physical properties of the generated molecules. Based on the separation performance of the extractant in liquid-liquid extraction and the relative importance of each index, the fuzzy comprehensive evaluation membership function was established, the analytic hierarchy process determined the mass ratio of each index, and the consistency test results were passed. The results of case study based on quantum chemical analysis demonstrated that effective determination of extractants for the analysis of benzene-cyclohexane systems. The results unanimously prove that the method has important theoretical significance and application value. 展开更多
关键词 Molecular design Element and chemical bonds Molecular simulation THERMODYNAMICS Solvent extraction
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Modulating Co-Co bonds average length in Co_(0.85)Se_(1-x)S_(x) to enhance conversion reaction for potassium storage
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作者 Daming Chen Yuchun Liu +5 位作者 Pan Feng Xiao Tao Zhiquan Huang Xiyu Zhang Min Zhou Jian Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期111-121,共11页
While alloying transition metal chalcogenides(TMCs)with other chalcogen elements can effectively improve their conductivity and electrochemical properties,the optimal alloying content is still uncertain.In this study,... While alloying transition metal chalcogenides(TMCs)with other chalcogen elements can effectively improve their conductivity and electrochemical properties,the optimal alloying content is still uncertain.In this study,we study the influence of dopant concentration on the chemical bonds in TMC and reveal the associated stepwise conversion reaction mechanism for potassium ion storage.According to density function theory calculations,appropriate S-doping in Co0.85Se(Co_(0.85)Se_(1-x)S_(x))can reduce the average length of Co-Co bonds because of the electronegativity variation,which is thermodynamically favourable to the phase transition reactions.The optimal Se/S ratio(x=0.12)for the conductivity has been obtained from experimental results.When assembled as an anode in potassium-ion batteries(PIBs),the sample with optimized Se/S ratio exhibits extraordinary electrochemical performance.The rate performance(229.2 mA h g^(-1)at 10 A g^(-1))is superior to the state-of-the-art results.When assembled with Prussian blue(PB)as a cathode,the pouch cell exhibits excellent performance,demonstrating its great potential for applications.Moreover,the stepwise K+storage mechanism caused by the coexistence of S and Se is revealed by in-situ X-ray diffraction and ex-situ transmission electron microscopy techniques.Hence,this work not only provides an effective strategy to enhance the electrochemical performance of transition metal chalcogenides but also reveals the underlying mechanism for the construction of advanced electrode materials. 展开更多
关键词 Co_(0.85)Se_(1-x)S_(x) Co-Co bonds Phase transition reactions Optimal Se/s Potassium ion batteries
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Interfacial coordination bonds accelerate charge separation for unprecedented hydrogen evolution over S-scheme heterojunction
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作者 Chunxue Li Hao Lu +4 位作者 Guixiang Ding Tianyi Ma Shiyong Liu Li Zhang Guangfu Liao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期174-184,共11页
Inspired by natural photosynthesis,fabricating high-performance S-scheme heterojunction is regarded as a successful tactic to address energy and environmental issues.Herein,NH_(2)-MIL-125(Ti)/Zn_(0.5)Cd_(0.5)S/NiS(NMT... Inspired by natural photosynthesis,fabricating high-performance S-scheme heterojunction is regarded as a successful tactic to address energy and environmental issues.Herein,NH_(2)-MIL-125(Ti)/Zn_(0.5)Cd_(0.5)S/NiS(NMT/ZCS/NiS)S-scheme heterojunction with interfacial coordination bonds is successfully synthesized through in-situ solvothermal strategy.Notably,the optimal NMT/ZCS/NiS S-scheme heterojunction exhibits comparable photocatalytic H_(2)evolution(PHE)rate of about 14876.7μmol h^(−1)g^(−1)with apparent quantum yield of 24.2%at 420 nm,which is significantly higher than that of recently reported MOFs-based photocatalysts.The interfacial coordination bonds(Zn–N,Cd–N,and Ni–N bonds)accelerate the separation and transfer of photogenerated charges,and the NiS as cocatalyst can provide more catalytically active sites,which synergistically improve the photocatalytic performance.Moreover,theoretical calculation results display that the construction of NMT/ZCS/NiS S-scheme heterojunction also optimize the binding energy of active site-adsorbed hydrogen atoms to enable fast adsorption and desorption.Photoassisted Kelvin probe force microscopy,in-situ irradiation X-ray photoelectron spectroscopy,femtosecond transient absorption spectroscopy,and theoretical calculations provide sufficient evidence of the S-scheme charge migration mechanism.This work offers unique viewpoints for simultaneously accelerating the charge dynamics and optimizing the binding strength between the active sites and hydrogen adsorbates over S-scheme heterojunction. 展开更多
关键词 Interfacial coordination bond S-schemeheterojunction Photocatalytic H_(2)evolution Charge dynamics Free energy barrier
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Genetic Analysis of Two Novel GPI Variants Disrupting H Bonds and Localization Characteristics of 55 Gene Variants Associated with Glucose-6-phosphate Isomerase Deficiency
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作者 Bi-xin XI Si-ying LIU +3 位作者 Yu-ting XU De-dong ZHANG Qun HU Ai-guo LIU 《Current Medical Science》 SCIE CAS 2024年第2期426-434,共9页
Objective:Glucose-6-phosphate isomerase(GPI)deficiency is a rare hereditary nonspherocytic hemolytic anemia caused by GPI gene variants.This disorder exhibits wide heterogeneity in its clinical manifestations and mole... Objective:Glucose-6-phosphate isomerase(GPI)deficiency is a rare hereditary nonspherocytic hemolytic anemia caused by GPI gene variants.This disorder exhibits wide heterogeneity in its clinical manifestations and molecular characteristics,often posing challenges for precise diagnoses using conventional methods.To this end,this study aimed to identify the novel variants responsible for GPI deficiency in a Chinese family.Methods:The clinical manifestations of the patient were summarized and analyzed for GPI deficiency phenotype diagnosis.Novel compound heterozygous variants of the GPI gene,c.174C>A(p.Asn58Lys)and c.1538G>T(p.Trp513Leu),were identified using whole-exome and Sanger sequencing.The AlphaFold program and Chimera software were used to analyze the effects of compound heterozygous variants on GPI structure.Results:By characterizing 53 GPI missense/nonsense variants from previous literature and two novel missense variants identified in this study,we found that most variants were located in exons 3,4,12,and 18,with a few localized in exons 8,9,and 14.This study identified novel compound heterozygous variants associated with GPI deficiency.These pathogenic variants disrupt hydrogen bonds formed by highly conserved GPI amino acids.Conclusion:Early family-based sequencing analyses,especially for patients with congenital anemia,can help increase diagnostic accuracy for GPI deficiency,improve child healthcare,and enable genetic counseling. 展开更多
关键词 glucose-6-phosphate isomerase deficiency whole-exome sequencing compound heterozygous variants genetic characterization hydrogen bond
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KVPO_(4)F/carbon nanocomposite with highly accessible active sites and robust chemical bonds for advanced potassium-ion batteries 被引量:2
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作者 Jianzhi Xu Liping Duan +3 位作者 Jiaying Liao Haowei Tang Jun Lin Xiaosi Zhou 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第5期1469-1478,共10页
KVPO_(4)F(KVPF)has been extensively investigated as the potential cathode material for potassium-ion batteries(PIBs)owing to its high theoretical capacity,superior operating voltage,and three-dimensional Kt conduction... KVPO_(4)F(KVPF)has been extensively investigated as the potential cathode material for potassium-ion batteries(PIBs)owing to its high theoretical capacity,superior operating voltage,and three-dimensional Kt conduction pathway.Nevertheless,the electrochemical behavior of KVPF is limited by the inherent poor electronic conductivity of the phosphate framework and unstable electrode/electrolyte interface.To address the above issues,this work proposes an infiltration-calcination method to confine the in-situ grown KVPF into the mesoporous carbon CMK-3(denoted KVPF@CMK-3).The assembled KVPF@CMK-3 nanocomposite features three-dimensional interconnected carbon channels,which not only offer abundant active sites and significantly accelerate K t/electron transport,but also prevent the growth of KVPF nanoparticle agglomerates,hence stabilizing the structure of the material.Additionally,V–F–C bonds are created at the interface of KVPF and CMK-3,which reduce the loss of F and stabilize the electrode interface.Thus,when tested as a cathode material for PIBs,the KVPF@CMK-3 nanocomposite delivers superior reversible capacitiy(103.2 mAh g^(-1) at 0.2 C),outstanding rate performance(90.1 mAh g^(-1) at 20 C),and steady cycling performance(92.2 mAh g^(-1) at 10 C and with the retention of 88.2%after 500 cycles).Moreover,its potassium storage mechanism is further examined by ex-situ XRD and ex-situ XPS techniques.The above synthetic strategy demonstrates the potential of KVPF@CMK-3 to be applied as the cathode for PIBs. 展开更多
关键词 Potassium-ion batteries CATHODE KVPO_(4)F CMK-3 V–F–C bond
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Estimating heat capacities of liquid organic compounds based on elements and chemical bonds contribution 被引量:1
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作者 Li Xia Yule Pan +4 位作者 Tingting Zhao Xiaoyan Sun Shaohui Tao Yushi Chen Shuguang Xiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期30-38,共9页
Molecular property depends on the property, the number of the elements, and the interaction between elements(such as chemical bonds). Based on the above-mentioned idea, two methods to estimate the isobaric heat capaci... Molecular property depends on the property, the number of the elements, and the interaction between elements(such as chemical bonds). Based on the above-mentioned idea, two methods to estimate the isobaric heat capacity of liquids organic compounds were developed. Ten elements groups and 32 chemical bond groups were defined by considering the structure of organic compounds. The group contribution values and correlation parameters were regressed by the ridge regression method with the experiment data of 1137 compounds. The heat capacity can be calculated by summating the contributions of the elements and chemical bond groups. The two methods were compared with existing group contribution methods, such as Chickos, Zabransky-Ruzicka, and Zdenka Kolska. The results show that those new estimation methods' overall average relative deviations were 5.81% and 5.71%, which were lower than the other three methods. Those methods were more straightforward in compound splitting.Those new methods can be used to estimate the liquid heat capacity of silicon-containing compounds,which the other three methods cannot estimate. The new methods are more accessible, broader, and more accurate. Therefore, this research has important scientific significance and vast application prospects. 展开更多
关键词 Thermodynamic Properties MODEL PREDICTION Elements and Chemical bonds
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Ni-catalyzed carbon–carbon bonds cleavage of mixed polyolefin plastics waste 被引量:1
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作者 Xiaoqin Si Jiali Chen +8 位作者 Zhengwei Wang Yue Hu Zhiwen Ren Rui Lu Lu Liu Jing Zhang Liwei Pan Rui Cai Fang Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期562-569,I0014,共9页
The inert carbon–carbon(C–C) bonds cleavage is a main bottleneck in the chemical upcycling of recalcitrant polyolefin plastics waste. Here we develop an efficient strategy to catalyze the complete cleavage of C–C b... The inert carbon–carbon(C–C) bonds cleavage is a main bottleneck in the chemical upcycling of recalcitrant polyolefin plastics waste. Here we develop an efficient strategy to catalyze the complete cleavage of C–C bonds in mixed polyolefin plastics over non-noble metal catalysts under mild conditions. The nickelbased catalyst involving Ni_(2)Al_(3) phase enables the direct transformation of mixed polyolefin plastics into natural gas, and the gas carbon yield reaches up to 89.6%. Reaction pathway investigation reveals that natural gas comes from the stepwise catalytic cleavage of C–C bonds in polypropylene, and the catalyst prefers catalytic cleavage of terminal C–C bond in the side-chain with the low energy barrier.Additionally, our developed approach is evaluated by the technical economic analysis for an economically competitive production process. 展开更多
关键词 Ni-based catalyst Mixed polyolefin plastics C–C bonds cleavage
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Functional zirconium phosphate nanosheets enabled transfer hydrogenolysis of aromatic ether bonds over a low usage of Ru nanocatalysts
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作者 Jinliang Song Yayun Pang +2 位作者 Chenglei Xiao Huizhen Liu Buxing Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期373-380,I0009,共9页
Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high activity.Herei... Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high activity.Herein,we designed porous zirconium phosphate nanosheet-supported Ru nanocatalysts(Ru/ZrPsheet)as the heterogeneous catalyst by a process combining ball milling and molten-salt(KNO_(3)).Very interestingly,the fabricated Ru/ZrPsheetshowed good catalytic performance on the transfer hydrogenolysis of various types of aromatic ether bonds contained in lignin,i.e.,4-O-5,a-O-4,β-O-4,and aryl-O-CH3,over a low Ru usage(<0.5 mol%)without using any acidic/basic additive.Detailed investigations indicated that the properties of Ru and the support were indispensable.The excellent activity of Ru/ZZrPsheetoriginated from the strong acidity and basicity of ZrPsheetand the higher electron density of metallic Ru0as well as the nanosheet structure of ZrPsheet. 展开更多
关键词 Valorization of lignin Aromatic ether bonds Transfer hydrogenolysis synergistic cooperation Zirconium phosphate nanosheets
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A Self-Healing and Nonflammable Cross-Linked Network Polymer Electrolyte with the Combination of Hydrogen Bonds and Dynamic Disulfide Bonds for Lithium Metal Batteries
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作者 Kai Chen Yuxue Sun +2 位作者 Xiaorong Zhang Jun Liu Haiming Xie 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期106-113,共8页
The self-healing solid polymer electrolytes(SHSPEs)can spontaneously eliminate mechanical damages or micro-cracks generated during the assembly or operation of lithium-ion batteries(LIBs),significantly improving cycli... The self-healing solid polymer electrolytes(SHSPEs)can spontaneously eliminate mechanical damages or micro-cracks generated during the assembly or operation of lithium-ion batteries(LIBs),significantly improving cycling performance and extending service life of LIBs.Here,we report a novel cross-linked network SHSPE(PDDP)containing hydrogen bonds and dynamic disulfide bonds with excellent self-healing properties and nonflammability.The combination of hydrogen bonding between urea groups and the metathesis reaction of dynamic disulfide bonds endows PDDP with rapid self-healing capacity at 28°C without external stimulation.Furthermore,the addition of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(EMIMTFSI)improves the ionic conductivity(1.13×10^(−4)S cm^(−1)at 28°C)and non-flammability of PDDP.The assembled Li/PDDP/LiFePO_(4)cell exhibits excellent cycling performance with a discharge capacity of 137 mA h g^(−1)after 300 cycles at 0.2 C.More importantly,the self-healed PDDP can recover almost the same ionic conductivity and cycling performance as the original PDDP. 展开更多
关键词 cross-linked network dynamic disulfide bonds lithium-ion batteries NONFLAMMABLE self-healing solid polymer electrolytes
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Improving the Heat Resistance ofβ-1,4 Glucanase by Introducing Disulfide Bonds
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作者 Guodong WANG Junqing WANG 《Agricultural Biotechnology》 CAS 2023年第2期32-37,共6页
Each possible pair of residues inβ-1,4 glucanase for disulfide formation was assessed using online websites,and four pairs L28C-S256C,Q41C-P278C,S122C-N163C and A184C-A215C were selected.Accordingly,four recombinant ... Each possible pair of residues inβ-1,4 glucanase for disulfide formation was assessed using online websites,and four pairs L28C-S256C,Q41C-P278C,S122C-N163C and A184C-A215C were selected.Accordingly,four recombinant plasmids pET28a(+)EccslH28,pET28a(+)EccslH41,pET28a(+)EccslH122 and pET28a(+)EccslH184 were prepared and transformed into E.coli to express the recombinant enzymes.Then analysis on enzymatic properties showed that T50 of the recombinant enzymes was increased from 10 min for EccslHt2 to 90 min for EccslH28 and 40 min for EccslH41 at 70℃,while their optimum pH value and pH stability were not affected,which proved that the introduction of disulfide bond improved the thermal stability ofβ-1,4 glucanase. 展开更多
关键词 β-1 4-Glucanase Disulfide bond Thermal stability Plasmid construction
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Mineral cleavage nature and surface energy: Anisotropic surface broken bonds consideration 被引量:18
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作者 高志勇 孙伟 胡岳华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第9期2930-2937,共8页
The population of surface broken bonds of some typical sulfide, oxide and salt-type minerals which may belong to cubic, tetragonal, hexagonal, or orthorhombic system, were calculated. In terms of the calculation resul... The population of surface broken bonds of some typical sulfide, oxide and salt-type minerals which may belong to cubic, tetragonal, hexagonal, or orthorhombic system, were calculated. In terms of the calculation results, the cleavage natures of these minerals were analyzed, and the relationship between surface broken bonds density and surface energy was also established. The results show that the surface broken bonds properties could be used to predict the cleavage nature of most of minerals, and the predicted cleavage planes agree well with those reported in previous literature. Moreover, this work explored a rule that, surface broken bonds density is directly related to surface energy with determination coefficient(R2) of over 0.8, indicating that the former is a dominant factor to determine the latter. Therefore, anisotropic surface broken bonds density can be used to predict the stability of mineral surface and the reactivity of surface atoms. 展开更多
关键词 surface broken bonds CLEAVAGE surface energy pyrite SPHALERITE CASSITERITE rutile HEMATITE
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Dilute Aqueous-Aprotic Electrolyte Towards Robust Zn-Ion Hybrid Supercapacitor with High Operation Voltage and Long Lifespan 被引量:2
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作者 Shuilin Wu Yibing Yang +6 位作者 Mingzi Sun Tian Zhang Shaozhuan Huang Daohong Zhang Bolong Huang Pengfei Wang Wenjun Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期1-12,共12页
With the merits of the high energy density of batteries and power density of supercapacitors,the aqueous Zn-ion hybrid supercapacitors emerge as a promising candidate for applications where both rapid energy delivery ... With the merits of the high energy density of batteries and power density of supercapacitors,the aqueous Zn-ion hybrid supercapacitors emerge as a promising candidate for applications where both rapid energy delivery and moderate energy storage are required.However,the narrow electrochemical window of aqueous electrolytes induces severe side reactions on the Zn metal anode and shortens its lifespan.It also limits the operation voltage and energy density of the Zn-ion hybrid supercapacitors.Using'water in salt'electrolytes can effectively broaden their electrochemical windows,but this is at the expense of high cost,low ionic conductivity,and narrow temperature compatibility,compromising the electrochemical performance of the Zn-ion hybrid supercapacitors.Thus,designing a new electrolyte to balance these factors towards high-performance Zn-ion hybrid supercapacitors is urgent and necessary.We developed a dilute water/acetonitrile electrolyte(0.5 m Zn(CF_(3)SO_(3))_(2)+1 m LiTFSI-H_(2)O/AN)for Zn-ion hybrid supercapacitors,which simultaneously exhibited expanded electrochemical window,decent ionic conductivity,and broad temperature compatibility.In this electrolyte,the hydration shells and hydrogen bonds are significantly modulated by the acetonitrile and TFSI-anions.As a result,a Zn-ion hybrid supercapacitor with such an electrolyte demonstrates a high operating voltage up to 2.2 V and long lifespan beyond 120,000 cycles. 展开更多
关键词 Zn-ion supercapacitors Zn metal anode Electrolyte engineering Hydrogen bonds Solvation structures
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基于离散元法的耕层残膜拉伸性能研究
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作者 申世龙 张佳喜 +4 位作者 蒋永新 王毅超 刘旋峰 李金明 董文浩 《农业机械学报》 EI CAS CSCD 北大核心 2024年第7期132-141,共10页
由于耕层残膜回收机关键农机部件设计优化过程中缺乏准确的残膜离散元模型参数,在一定程度上制约了耕层残膜回收机残膜受力机理分析与机构优化改进。本文以棉田耕层残膜为研究对象,对耕层残膜含量和极限拉伸力进行测定,得到不同耕层深... 由于耕层残膜回收机关键农机部件设计优化过程中缺乏准确的残膜离散元模型参数,在一定程度上制约了耕层残膜回收机残膜受力机理分析与机构优化改进。本文以棉田耕层残膜为研究对象,对耕层残膜含量和极限拉伸力进行测定,得到不同耕层深度、不同厚度的残膜含量和极限拉伸力。根据测定结果,利用EDEM软件选用Hertz-Mindlin with Bonding接触模型对耕层残膜进行离散元模型参数标定,选用单位面积法向刚度、单位面积切向刚度、临界法向应力、临界切向应力、粘结半径、接触半径为试验因素。通过Plackett-Burman试验,确定影响Bond键的主要参数有单位面积法向刚度、临界法向应力和粘结半径。通过最陡爬坡试验和Box-Behnken试验,最终确定最优的Bonding模型显著参数单位面积法向刚度、临界法向应力、粘结半径分别为2.36×10^(5) N/m^(3)、6.47×10^(4) Pa、0.004 mm,对参数进行了仿真试验验证,误差为5.88%,满足要求。通过对比物理试验与仿真试验的拉伸过程耕层残膜状态与拉伸曲线,表明了耕层残膜模型合理性,为后期耕层残膜回收机仿真与膜土分离机理研究提供了理论支撑。 展开更多
关键词 棉田耕层残膜 极限拉伸力 离散元模型 Bonding模型 拉伸仿真试验
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Machine learning with active pharmaceutical ingredient/polymer interaction mechanism:Prediction for complex phase behaviors of pharmaceuticals and formulations 被引量:2
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作者 Kai Ge Yiping Huang Yuanhui Ji 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期263-272,共10页
The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceu... The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceutical formulations.In this work,a developed machine-learning model efficiently predicts the solubility of APIs in polymers by learning the phase equilibrium principle and using a few molecular descriptors.Under the few-shot learning framework,thermodynamic theory(perturbed-chain statistical associating fluid theory)was used for data augmentation,and computational chemistry was applied for molecular descriptors'screening.The results showed that the developed machine-learning model can predict the API-polymer phase diagram accurately,broaden the solubility data of APIs in polymers,and reproduce the relationship between API solubility and the interaction mechanisms between API and polymer successfully,which provided efficient guidance for the development of pharmaceutical formulations. 展开更多
关键词 Multi-task machine learning Density functional theory Hydrogen bond interaction MISCIBILITY SOLUBILITY
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Accelerating Oxygen Electrocatalysis Kinetics on Metal-Organic Frameworks via Bond Length Optimization 被引量:2
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作者 Fan He Yingnan Liu +10 位作者 Xiaoxuan Yang Yaqi Chen Cheng‑Chieh Yang Chung‑Li Dong Qinggang He Bin Yang Zhongjian Li Yongbo Kuang Lecheng Lei Liming Dai Yang Hou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期279-290,共12页
Metal-organic frameworks(MOFs)have been developed as an ideal platform for exploration of the relationship between intrinsic structure and catalytic activity,but the limited catalytic activity and stability has hamper... Metal-organic frameworks(MOFs)have been developed as an ideal platform for exploration of the relationship between intrinsic structure and catalytic activity,but the limited catalytic activity and stability has hampered their practical use in water splitting.Herein,we develop a bond length adjustment strategy for optimizing naphthalene-based MOFs that synthesized by acid etching Co-naphthalenedicarboxylic acid-based MOFs(donated as AE-CoNDA)to serve as efficient catalyst for water splitting.AE-CoNDA exhibits a low overpotential of 260 mV to reach 10 mA cm^(−2)and a small Tafel slope of 62 mV dec^(−1)with excellent stability over 100 h.After integrated AE-CoNDA onto BiVO_(4),photocurrent density of 4.3 mA cm^(−2)is achieved at 1.23 V.Experimental investigations demonstrate that the stretched Co-O bond length was found to optimize the orbitals hybridization of Co 3d and O 2p,which accounts for the fast kinetics and high activity.Theoretical calculations reveal that the stretched Co-O bond length strengthens the adsorption of oxygen-contained intermediates at the Co active sites for highly efficient water splitting. 展开更多
关键词 Metal-organic frameworks Bond length adjustment Spin state transition Orbitals hybridization Water splitting
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高压辊磨对超微细粒嵌布磁铁矿破碎和预选的影响
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作者 彭畅 周文波 +3 位作者 王永刚 朱照强 彭宇 程义桓 《烧结球团》 北大核心 2024年第2期74-82,106,共10页
针对某超微细粒嵌布贫磁铁矿开发难度大、原矿入磨品位偏低、磨矿能源消耗高的问题,本文进行高压辊磨—预选工艺试验,通过对比两种破碎产品的粒度特征、相对可磨度、Bond球磨功指数、预选指标,并结合破碎产品的表面形貌和内部微裂纹,研... 针对某超微细粒嵌布贫磁铁矿开发难度大、原矿入磨品位偏低、磨矿能源消耗高的问题,本文进行高压辊磨—预选工艺试验,通过对比两种破碎产品的粒度特征、相对可磨度、Bond球磨功指数、预选指标,并结合破碎产品的表面形貌和内部微裂纹,研究高压辊磨所产生的微裂纹对于磨矿和分选的影响。结果表明:相对于常规破碎,辊压产品中<0.074 mm粒级质量分数增加了14.69个百分点,>2 mm的粗粒级质量分数降低了8.59个百分点;在160 kA/m预选磁场强度下,辊压产品的铁品位为31.96%,提高了1.46个百分点;磁性铁的回收率高达99.45%,提高了1.17个百分点,抛尾率提高了5.03个百分点。相对可磨度试验结果表明,当磨矿细度达到<0.03 mm粒级质量分数为85%时,辊压产品的耗时相对于常规破碎缩短了42.13%。辊压产品的Bond球磨功指数(目标粒度<0.15 mm)降低了27.90%。偏光显微镜和SEM扫描电镜结果表明,辊压产品结构疏松多孔、微裂纹发育充分,能产生大量的晶界裂纹,解离更充分。 展开更多
关键词 高压辊磨 超微细粒 嵌布 磁铁矿 预选 可磨性 Bond球磨功指数
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Failure characterization of fully grouted rock bolts under triaxial testing 被引量:1
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作者 Hadi Nourizadeh Ali Mirzaghorbanali +3 位作者 Mehdi Serati Elamin Mutaz Kevin McDougall Naj Aziz 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期778-789,共12页
Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic st... Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic stress conditions.Under these conditions,it is assumed that the intermediate principal stress(σ_(2))equals the minimum principal stress(σ_(3)).This assumption overlooks the potential variations in magnitudes of in situ stress conditions along all three directions near an underground opening where a rock bolt is installed.In this study,a series of push tests was meticulously conducted under triaxial conditions.These tests involved applying non-uniform confining stresses(σ_(2)≠σ_(3))to cubic specimens,aiming to unveil the previously overlooked influence of intermediate principal stresses on the strength properties of rock bolts.The results show that as the confining stresses increase from zero to higher levels,the pre-failure behavior changes from linear to nonlinear forms,resulting in an increase in initial stiffness from 2.08 kN/mm to 32.51 kN/mm.The load-displacement curves further illuminate distinct post-failure behavior at elevated levels of confining stresses,characterized by enhanced stiffness.Notably,the peak load capacity ranged from 27.9 kN to 46.5 kN as confining stresses advanced from σ_(2)=σ_(3)=0 to σ_(2)=20 MPa and σ_(3)=10 MPa.Additionally,the outcomes highlight an influence of confining stress on the lateral deformation of samples.Lower levels of confinement prompt overall dilation in lateral deformation,while higher confinements maintain a state of shrinkage.Furthermore,diverse failure modes have been identified,intricately tied to the arrangement of confining stresses.Lower confinements tend to induce a splitting mode of failure,whereas higher loads bring about a shift towards a pure interfacial shear-off and shear-crushed failure mechanism. 展开更多
关键词 Rock bolts Bolt-grout interface Bond strength Push test Triaxial tests
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Numerical and experimental investigation on hydraulic-electric rock fragmentation of heterogeneous granite 被引量:1
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作者 Xiaohua Zhu Ling He +3 位作者 Weiji Liu Yunxu Luo Youjian Zhang Wuji Tang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期15-29,共15页
Hydraulic-electric rock fragmentation(HERF)plays a significant role in improving the efficiency of high voltage pulse rock breaking.However,the underlying mechanism of HERF remains unclear.In this study,considering th... Hydraulic-electric rock fragmentation(HERF)plays a significant role in improving the efficiency of high voltage pulse rock breaking.However,the underlying mechanism of HERF remains unclear.In this study,considering the heterogeneity of the rock,microscopic thermodynamic properties,and shockwave time domain waveforms,based on the shockwave model,digital imaging technology and the discrete element method,the cyclic loading numerical simulations of HERF is achieved by coupling electrical,thermal,and solid mechanics under different formation temperatures,confining pressure,initial peak voltage,electrode bit diameter,and loading times.Meanwhile,the HERF discharge system is conducive to the laboratory experiments with various electrical parameters and the resulting broken pits are numerically reconstructed to obtain the geometric parameters.The results show that,the completely broken area consists of powdery rock debris.In the pre-broken zone,the mineral cementation of the rock determines the transition of type CⅠcracks to type CⅡand type CⅢcracks.Furthermore,the peak pressure of the shockwave increased with initial peak voltage but decreased with electrode bit diameter,while the wave front time reduced.Moreover,increasing well depth,formation temperature and confining pressure augment and inhibit HERF,but once confining pressure surpassed the threshold of 60 MPa for 152.40,215.90,and 228.60 mm electrode bits,and 40 MPa for 309.88 mm electrode bits,HERF is promoted.Additionally,for the same kind of rock,the volume and width of the broken pit increase with higher initial peak voltage and rock fissures will promote HERF.Eventually,the electrode drill bit with a 215.90 mm diameter is more suitable for drilling pink granite.This research contributes to a better microscopic understanding of HERF and provides valuable insights for electrode bit selection,as well as the optimization of circuit parameters for HERF technology. 展开更多
关键词 Hydraulic-electric rock fragmentation SHOCKWAVE Thermodynamics MICROCRACKS Weak Linear Parallel Bond Model
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基于活塞压载试验预测高压辊磨机静压功指数的方法
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作者 吴俊杰 马阳 +4 位作者 崔少文 刘恩建 郭小飞 代淑娟 李丽匣 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期1272-1280,共9页
以Bond第三粉碎理论为基础,提出将静压功指数作为评价矿石高压辊磨机料层粉碎比能耗的指标。研究活塞压载试验中不同施载压力对矿石粒度、比能耗和破碎比的影响,确定不同矿石活塞压载试验的适宜条件。通过试验测定3种矿石的高压辊磨机... 以Bond第三粉碎理论为基础,提出将静压功指数作为评价矿石高压辊磨机料层粉碎比能耗的指标。研究活塞压载试验中不同施载压力对矿石粒度、比能耗和破碎比的影响,确定不同矿石活塞压载试验的适宜条件。通过试验测定3种矿石的高压辊磨机静压功指数,并将其与高压辊磨机生产实践中粉碎同种矿石的净输入功率进行对比。研究结果表明:在活塞压载条件试验中,随着压力的增加,金矿、磁铁矿和钒钛磁铁矿这3种矿石粉碎产品细粒级质量分数增高、粒度分布更加均匀,三者粉碎效果的差异逐渐减小;在加载压力为80 MPa、加载速度为0.2 mm/s的情况下,金矿、磁铁矿和钒钛磁铁矿这3种矿石的高压辊磨机静压功指数分别为1.36、1.44和1.42 kW·h/t,试验所得高压辊磨机静压功指数与工业生产实际中净比能耗的相对误差绝对值在5.26%以内。试验结果可为高压辊磨机静压功指数的预测及设备选型提供理论基础。 展开更多
关键词 高压辊磨机 Bond粉碎理论 活塞压载试验 静压功指数 预测模型
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