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Solar-driven methane-to-ethanol conversion by “intramolecular junction” with both high activity and selectivity 被引量:1
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作者 Qijun Tang Wenguang Tu Zhigang Zou 《Chinese Journal of Structural Chemistry》 2025年第6期6-7,共2页
Methane(CH4),the predominant component of natural gas and shale gas,is regarded as a promising carbon feedstock for chemical synthesis[1].However,considering the extreme stability of CH4 molecules,it's quite chall... Methane(CH4),the predominant component of natural gas and shale gas,is regarded as a promising carbon feedstock for chemical synthesis[1].However,considering the extreme stability of CH4 molecules,it's quite challenging in simultaneously achieving high activity and selectivity for target products under mild conditions,especially when synthesizing high-value C2t chemicals such as ethanol[2].The conversion of methane to ethanol by photocatalysis is promising for achieving transformation under ambient temperature and pressure conditions.Currently,the apparent quantum efficiency(AQE)of solar-driven methane-to-ethanol conversion is generally below 0.5%[3,4].Furthermore,the stability of photocatalysts remains inadequate,offering substantial potential for further improvement. 展开更多
关键词 natural gas shale gasis target products carbon feedstock chemical synthesis howeverconsidering intramolecular junction solar driven methane ethanol conversion
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Hydrothermal conversion from hydrogarnet to hydroandradite based on alumina recovery from red mud
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作者 Hong-fei WU Xiao-lin PAN +3 位作者 Ji-long LIU Feng QIU Tun HE Hai-yan YU 《Transactions of Nonferrous Metals Society of China》 2026年第1期309-322,共14页
To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM ... To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM methods,and a novel hydrothermal process based on the conversion principle was finally proposed.The crystal structure simulation shows that the HA with varied silicon saturation coefficients is more stable than HG,and the HA with a high iron substitution coefficient is more difficult to be converted from HG.The(110)plane of Fe_(2)O_(3) is easier to combine with HG to form HA,and the binding energy is 81.93 kJ/mol.The effects of raw material ratio,solution concentration and hydrothermal parameters on the conversion from HG to HA were revealed,and the optimal conditions for the alumina recovery were obtained.The recovery efficiencies of alumina and Na_(2)O from the RM are 63.06%and 97.34%,respectively,and the Na_(2)O content in the treated RM is only 0.13%. 展开更多
关键词 HYdROGaRNET hydroandradite structural stability hydrothermal conversion red mud
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Design and experimental validation of a low-impact wing locking/release mechanism based on energy conversion strategy
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作者 Yanbing Wang Honghao Yue +5 位作者 Jun Wu Xueting Pan Fei Yang Yong Zhao Jicheng Liu Xue Bai 《Defence Technology(防务技术)》 2026年第1期241-256,共16页
Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or ... Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or attitude instability,seriously compromising mission reliability.To address this engineering challenge,this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy.Through establishing a DOF constraint framework system,this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process,reveals the generation mechanism of impact loads,and conducts research on low-impact design based on energy conversion strategy.Building on this foundation,a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed,which increases frictional contact time and reduces the energy release rate,thereby achieving low-impact characteristics.The mechanism's performance was validated through physical prototype development and systematic functional testing(including unlocking force,synchronization,and impact tests).Experimental results demonstrate:(1)Under 14 kN preload condition,the maximum unlocking force was only 92.54 N,showing a linear relationship with preload that satisfies the"strong-connection/weak-unlock"design requirement;(2)Wing separation was completed within 46 ms,with synchronization time difference among three separation mechanisms stably controlled within 12-14 ms,proving rapid and reliable operation;(3)The unlocking impact acceleration ranged between 26 and 73 g,below the 100 g design limit,confirming the effectiveness of the energy conversion strategy.The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies.The synergistic optimization mechanism of"structural load reduction and performance improvement"provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering. 展开更多
关键词 Hypersonic vehicle Energy conversion strategy Low-impact Wing separation Locking/release mechanism
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Kinetic simulation of hydrocarbon generation and its application to in-situ conversion of shale oil
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作者 ZHANG Bin YU Cong +3 位作者 CUI Jingwei MI Jingkui LI Huadong HE Fei 《Petroleum Exploration and Development》 2019年第6期1288-1296,共9页
The kinetic parameters of hydrocarbon generation are determined through experimental simulation and mathematical calculation using four typical samples selected from the Cretaceous Nenjiang Formation in the northwest ... The kinetic parameters of hydrocarbon generation are determined through experimental simulation and mathematical calculation using four typical samples selected from the Cretaceous Nenjiang Formation in the northwest of Songliao Basin,Chang 7 Member of Triassic Yanchang Formation in the southwest of Ordos Basin,Paleogene in the southwest of Qaidam Basin,and Lucaogou Formation of Jimusar Sag in the east of Junggar Basin.The results show that activation energy of hydrocarbon generation of organic matter is closely related to maturity and mainly ranges between 197 kJ/mol and 227 kJ/mol.On this basis,the temperature required for organic matter in shale to convert into oil was calculated.The ideal heating temperature is between 270℃and 300℃,and the conversation rate can reach 90%after 50-300 days of heating at constant temperature.When the temperature rises at a constant rate,the temperature corresponding to the major hydrocarbon generation period ranges from 225 to 350℃at the temperature rise rate of 1-150℃/month.In order to obtain higher economic benefits,it is suggested to adopt higher temperature rise rate(60-150℃/month).The more reliable kinetic parameters obtained can provide a basis for designing more reasonable scheme of in-situ heating conversion. 展开更多
关键词 HYdROCaRBON GENERaTION kinetics shale oil activation energy IN-SITU conversion Permian Lucaogou FORMaTION Triassic Yanchang FORMaTION Chang 7 Member Cretaceous Nenjiang FORMaTION HYdROCaRBON GENERaTION simulation
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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2 被引量:1
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作者 Qing He Zhen Wang +5 位作者 Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen 《Neural Regeneration Research》 SCIE CAS 2025年第6期1801-1815,共15页
Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders.... Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain. 展开更多
关键词 aQUaPORIN-4 ascl1 aSTROCYTE cortex dlx2 gap junction glia-to-neuron conversion neural regeneration Neurod1 REPROGRaMMING
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Conversion treatment for advanced intrahepatic cholangiocarcinoma:Opportunities and challenges 被引量:2
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作者 Jun-Jie Liu Mi Zhou +2 位作者 Tong Yuan Zhi-Yong Huang Zun-Yi Zhang 《World Journal of Gastroenterology》 2025年第15期24-41,共18页
The prevalence of intrahepatic cholangiocarcinoma(ICC)is increasing globally.Despite advancements in comprehending this intricate malignancy and formulating novel therapeutic approaches over the past few decades,the p... The prevalence of intrahepatic cholangiocarcinoma(ICC)is increasing globally.Despite advancements in comprehending this intricate malignancy and formulating novel therapeutic approaches over the past few decades,the prognosis for ICC remains poor.Owing to the high degree of malignancy and insidious onset of ICC,numerous cases are detected at intermediate or advanced stages of the disease,hence eliminating the chance for surgical intervention.Moreover,because of the highly invasive characteristics of ICC,recurrence and metastasis postresection are prevalent,leading to a 5-year survival rate of only 20%-35%following surgery.In the past decade,different methods of treatment have been investigated,including transarterial chemoembolization,transarterial radioembolization,radiotherapy,systemic therapy,and combination therapies.For certain patients with advanced ICC,conversion treatment may be utilized to facilitate surgical resection and manage disease progression.This review summarizes the definition of downstaging conversion treatment and presents the clinical experience and evidence concerning conversion treatment for advanced ICC. 展开更多
关键词 Intrahepatic cholangiocarcinoma conversion treatment dOWNSTaGING Combination therapy Chemotherapy IMMUNOTHERaPY Locoregional therapies
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Nanostructured energy materials for electrochemical energy conversion and storage: A review 被引量:40
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作者 Xueqiang Zhang Xinbing Cheng Qiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期967-984,共18页
Nanostructured materials have received tremendous interest due to their unique mechanical/electrical properties and overall behavior contributed by the complex synergy of bulk and interfacial properties for efficient ... Nanostructured materials have received tremendous interest due to their unique mechanical/electrical properties and overall behavior contributed by the complex synergy of bulk and interfacial properties for efficient and effective energy conversion and storage. The booming development of nanotechnology affords emerging but effective tools in designing advanced energy material. We reviewed the significant progress and dominated nanostructured energy materials in electrochemical energy conversion and storage devices, including lithium ion batteries, lithium-sulfur batteries, lithium-oxygen batteries, lithium metal batteries, and supercapacitors. The use of nanostructured electrocatalyst for effective electrocatalysis in oxygen reduction and oxygen evolution reactions for fuel cells and metal-air batteries was also included. The challenges in the undesirable side reactions between electrolytes and electrode due to high electrode/electrolyte contact area, low volumetric energy density of electrode owing to low tap density, and uniform production of complex energy materials in working devices should be overcome to fully demonstrate the advanced energy nanostructures for electrochemical energy conversion and storage. The energy chemistry at the interfaces of nanostructured electrode/electrolyte is highly expected to guide the rational design and full demonstration of energy materials in a working device. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 Energy materials Lithium ion batteries Lithium sulfur batteries Lithium oxygen batteries Lithium metal SUPERCaPaCITORS Oxygen reduction reaction Oxygen evolution reaction ELECTROCaTaLYSIS Nanostructures Energy conversion and storage
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Editorial for special issue on high -entropy and multicomponent-doped materials for energy applications: Innovations in energy conversion and storage
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作者 Konrad Świerczek Kun Zheng +2 位作者 Liuting Zhang Yihan Ling Mingjiong Zhou 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2593-2597,共5页
Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy... Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy Applications:Innovations in Energy Conversion and Storage.”This collection highlights the latest research developments in the preparation,optimizing properties,and exploring potential applications of high-entropy materials(HEMs)and other com-pounds with increased configurational entropy. 展开更多
关键词 energy applications innovations configurational entropy energy storage high entropy materials energy conversion energy conversion storage multicomponent doped materials
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Conversion of Unresectable to Resectable Liver Metastases from Colorectal Carcinoma Using Hepatic Arterial Chronomodulated Chemotherapy: A Case Report and Short Literature Review
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作者 Evgeny Y. Parnes Maria S. Sayapina +5 位作者 Alexey A. Tryakin Mohamed Bouchahda Pasquale F. Innominato Jean-Francois Morere Francis A. Levi Rene Adam 《Surgical Science》 2018年第10期358-366,共9页
Background: The regional chronomodulated hepatic arterial infusion chemotherapy (HAIC) is an effective regimen for the treatment of patients with unresectable liver metastases from colorectal cancer, especially for th... Background: The regional chronomodulated hepatic arterial infusion chemotherapy (HAIC) is an effective regimen for the treatment of patients with unresectable liver metastases from colorectal cancer, especially for the conversion into resectability. Aim: To demonstrate that chronomodulated HAI triplet chemotherapy according to OPTILIV protocol is well tolerated and displayed high antitumor activity in this heavily-pretreated patient. Case Presentation: A 54 years old patient from Russia was treated for a tumor in the ascending colon presented with 13 hepatic metastases ranging from 0.3 to 2.7 cm in diameter. He underwent a laparoscopic right hemicolectomy, 12 cycles of FOLFIRINOX combined to bevacizumab for the last 5 cycles, resulting in a partial response according to CT scan. It was decided to perform a two-stage hepatectomy at Paul Brousse hospital: left partial hepatectomy allowed the excision of 9 lesions. Radio frequency ablation was performed in 2 nodular lesions. Afterwards, the patient received 5 cycles of chronomodulated triplet chemotherapy into the hepatic artery, according to the OPTILIV protocol design, yet without cetuximab, because of the KRAS mutation in the liver metastases, with a partial re-sponse. The patient could then undergo the second stage of the planned right hepatectomy, which turned out to be an R0 resection followed by receiving three courses of chronomodulated HAIC. Disease progression was documented after 3 months. Chronomodulated FOLFIRI chemotherapy was re-started intravenously, in combination with Aflibercept and it was associated with further disease progression. The genetic analysis of our patient’s cancer revealed a high level of MSI. The patient was included in the Phase 2 CheckMate-142 trial and received nivolumab 3 mg/kg every 2 weeks within 3 months. Treatment was discontinued due to ineffectiveness. Then the patient underwent radiotherapy geared towards reduction of pain. Afterwards, the patient died from the disease progression 2 years after the beginning of treatment. Conclusion: In this article, the authors report a clinical case with chronomodulated HAIC as rescue therapy in a heavily pretreated patient with metastatic colorectal cancer, allowing to achieve an objective response despite prior progression on FOLFIRINOX (the same triplet chemo by IV route). This strategy permitted to overcome drug resistance and to perform further complete resection of the liver me-tastases with prolonged patient survival. Thus, chronomodulated HAI is useful in patients with liver metastases from colorectal cancer and de-serves to be further assessed prospectively in clinical trials chemotherapy. 展开更多
关键词 The Regional Chronomodulated HEPaTIC aRTERIaL Infusion CHEMOTHERaPY Metastatic Colorectal Cancer conversion of UNRESECTaBLE to Resectable Liver METaSTaSES
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Low-coordination Cu_(3)motif for selective photocatalytic conversion of CO_(2)to ethanol
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作者 Yanping Qiu Lei Ge 《Chinese Journal of Structural Chemistry》 2025年第11期1-3,共3页
Photocatalytic CO_(2)reduction to multi-carbon(C^(2+))products using solar energy is a promising route to carbon neutrality[1].Among these products,ethanol has attracted significant attention due to its high energy de... Photocatalytic CO_(2)reduction to multi-carbon(C^(2+))products using solar energy is a promising route to carbon neutrality[1].Among these products,ethanol has attracted significant attention due to its high energy density and convenient storage.However,achieving high selectivity for ethanol remains challenging because the reaction involves complex multi-electron transfer processes,and the ethanol pathway shares the same intermediate with the ethylene pathway,while the ethylene pathway has a thermodynamic advantage[2].This phenomenon makes it difficult to precisely control C-C coupling selectivity. 展开更多
关键词 solar energy low coordination CU photocatalytic conversion ETHaNOL multi carbon products CO carbon neutrality
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Quadruple therapy with immunotherapy and chemotherapy as firstline conversion treatment for unresectable advanced gastric adenocarcinoma: A case report
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作者 Xiao-Yu Du Ren-Jie Xia +9 位作者 Li-Wen Shen Jian-Guo Ma Wei-Qing Yao Wei Xu Zhi-Peng Lin Liang-Bin Ma Guo-Qiang Niu Rui-Fang Fan Shu-Mei Xu Long Yan 《World Journal of Gastrointestinal Oncology》 2025年第4期503-514,共12页
BACKGROUND The treatment of gastric cancer remains highly challenging,particularly in cases of unresectable locally advanced or metastatic disease.Although chemotherapy and immunotherapy have shown some efficacy in su... BACKGROUND The treatment of gastric cancer remains highly challenging,particularly in cases of unresectable locally advanced or metastatic disease.Although chemotherapy and immunotherapy have shown some efficacy in such patients,significant limitations persist in extending survival and enhancing safety.To address these challenges,we designed an innovative first-line quadruple conversion therapy regimen that integrates a programmed cell death protein 1(PD-1)inhibitor with chemotherapy,and we successfully implemented this therapy regimen in the treatment of a patient with unresectable locally advanced gastric adenocarcinoma.CASE SUMMARY We report the case of a 55-year-old male who was diagnosed with unresectable locally advanced gastric adenocarcinoma and presented with intermittent epigastric pain and multiple lymph node metastases in the abdominal cavity,with the metastasis being notably large in size.The tumor tissue was negative for human epidermal growth factor receptor 2 by immunohistochemistry.Considering the patient's status,the multidisciplinary team decided to administer sintilimab in combination with albumin-bound paclitaxel(nab-paclitaxel),S-1,and oxaliplatin as a quadruple drug conversion therapy.After 4 cycles of conversion therapy,the patient's epigastric pain was significantly alleviated,his stool color normalized,the volume of the primary tumor and lymph node metastases was markedly reduced,and the tumor marker levels decreased to within the normal range.The patient subsequently underwent laparoscopic total gastrectomy with abdominal lymph node dissection,and postoperative pathological biopsy revealed a pathological complete response and R0 resection,after which the patient recovered to an excellent physical status.CONCLUSION To the best of our knowledge,this is the first reported case of unresectable locally advanced gastric adenocar-cinoma successfully treated with quadruple therapy with a PD-1 inhibitor and chemotherapy as a first-line conversion regimen.This first-line conversion therapy with the quadruple regimen may be effective and safe for unresectable locally advanced gastric adenocarcinoma. 展开更多
关键词 Unresectable locally advanced gastric adenocarcinoma conversion therapy IMMUNOTHERaPY Programmed cell death protein 1 inhibitors Sintilimab Case report
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Livelihood transition and traditional knowledge conversion towards sustainable rural development in mountainous regions: A Case of Hoang Lien National Park, Vietnam
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作者 Rebecca H.CHUNG LE Minh-Tu 《Journal of Mountain Science》 2025年第10期3790-3804,共15页
The study offers a conceptual framework illuminating sustainable rural development by a continuous cycling interplay among five interdependent systems,physical,social,economic,knowledge,and creative.The framework is a... The study offers a conceptual framework illuminating sustainable rural development by a continuous cycling interplay among five interdependent systems,physical,social,economic,knowledge,and creative.The framework is applied to analyze the livelihood transition in the economic system and conversion of traditional knowledge in the creative system for farm households engaged in large cardamom cultivation in Northern mountainous region in Vietnam.This study used a probit model to examine a data set comprising 300 households and confirmed that factors within the social and physical systems(such as labor,access to information,social networks,land use,and transportation infrastructure)determined livelihood transition to tourism employment within the economic system.In addition,the conversion of traditional knowledge in the creative system was found to be contingent upon non-farm employment and credit capital in the economic system,as well as traditional knowledge and knowledge exchange in the knowledge system.This study demonstrates how the sustainable development of rural agriculture can be achieved by converting traditional knowledge and transferring livelihood,contributing to attain Sustainable Development Goals 2(Zero Hunger)and SDG 12(Responsible Consumption and Production). 展开更多
关键词 Large cardamom cultivation Livelihood transition Mountainous regions Sustainable development Goals Sustainable rural development Tourism employment Traditional knowledge conversion
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Method to Increase Micro-controller A/D Conversion Speed
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作者 唐鹤权 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期128-131,共4页
The speed and cost of A/D conversion are conflict to each other. As micro-controller speed is increasing and its internal function is improving, full utilization of its internal resource can dramatically increase A/D ... The speed and cost of A/D conversion are conflict to each other. As micro-controller speed is increasing and its internal function is improving, full utilization of its internal resource can dramatically increase A/D conversion speed and without compromising conversion quality. MSP430F11x1 series micro-controller is exploited to increase A/D conversion speed. 展开更多
关键词 Micro-controller a/d conversion Speed and cost.
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Diamond related materials for energy storage and conversion applications
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作者 YU Si-yu WANG Xi-yan YANG Nian-jun 《新型炭材料(中英文)》 北大核心 2025年第4期973-992,共20页
Diamond combines many unique properties,including high stability,strong optical dispersion,excellent mechanical strength,and outstanding thermal conductivity.Its structure,surface groups,and electrical conductivity ar... Diamond combines many unique properties,including high stability,strong optical dispersion,excellent mechanical strength,and outstanding thermal conductivity.Its structure,surface groups,and electrical conductivity are also tunable,increasing its functional versatility.These make diamond and its related materials,such as its composites,highly promising for various applications in energy fields.This review summarizes recent advances and key achievements in energy storage and conversion,covering electrochemical energy storage(e.g.,batteries and supercapacitors),electrocatalytic energy conversion(e.g.,CO_(2)and nitrogen reduction reactions),and solar energy conversion(e.g.,photo-(electro)chemical CO_(2)and nitrogen reduction reactions,and solar cells).Current challenges and prospects related to the synthesis of diamond materials and the technologies for their energy applications are outlined and discussed. 展开更多
关键词 diamond related materials Electrochemical energy storage Electrocatalytic energy conversion Solar energy conversion Future energy application directions
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Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand 被引量:5
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作者 Yun-kai Ji Chang-ling Liu +4 位作者 Zhun Zhang Qing-guo Meng Le-le Liu Yong-chao Zhang Neng-you Wu 《China Geology》 2022年第2期276-284,共9页
Understanding the pore water conversion characteristics during hydrate formation in porous media is important to study the accumulation mechanism of marine gas hydrate.In this study,low-field NMR was used to study the... Understanding the pore water conversion characteristics during hydrate formation in porous media is important to study the accumulation mechanism of marine gas hydrate.In this study,low-field NMR was used to study the pore water conversion characteristics during methane hydrate formation in unsaturated sand samples.Results show that the signal intensity of T_(2) distribution isn’t affected by sediment type and pore pressure,but is affected by temperature.The increase in the pressure of hydrogen-containing gas can cause the increase in the signal intensity of T_(2) distribution.The heterogeneity of pore structure is aggravated due to the hydrate formation in porous media.The water conversion rate fluctuates during the hydrate formation.The sand size affects the water conversion ratio and rate by affecting the specific surface of sand in unsaturated porous media.For the fine sand sample,the large specific surface causes a large gas-water contact area resulting in a higher water conversion rate,but causes a large water-sand contact area resulting in a low water conversion ratio(C_(w)=96.2%).The clay can reduce the water conversion rate and ratio,especially montmorillonite(C_(w)=95.8%).The crystal layer of montmorillonite affects the pore water conversion characteristics by hindering the conversion of interlayer water. 展开更多
关键词 Porous media Unsaturated sand Methane hydrates Low-field NMR Pore water conversion Hydrate formation NGHs exploration trial engineering Oil and gas exploration engineering Shenhu area South China Sea
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Corrigendum to‘Tuning the nucleation kinetics of phosphate chemical conversion coating on Mg-Gd-Y-Zr magnesium alloy:The effect of pretreatment and organic additive’[Journal of Magnesium and Alloys 13(2025)207–218]
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作者 Siyu Sun Peng Zhou +5 位作者 Yan Chen JinTao Xiao Jingli Sun Yong Yuan Tao Zhang Fuhui Wang 《Journal of Magnesium and Alloys》 2025年第5期2433-2434,共2页
The authors regret that due to negligence,the picture was misplaced in the original manuscript,resulting in Fig.6d being incorrectly included.The correct version of Fig.6d is provided below for reference.This error do... The authors regret that due to negligence,the picture was misplaced in the original manuscript,resulting in Fig.6d being incorrectly included.The correct version of Fig.6d is provided below for reference.This error does not affect the conclusions of the study,and we apologize for any confusion it may have caused. 展开更多
关键词 nucleation kinetics fig d PRETREaTMENT phosphate chemical conversion coating organic additive magnesium alloy
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Origin of Magnetic Fields of Stellar Objects in the Universe Based on the 5D Projection Theory
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作者 Peter C. W. Fung K. W. Wong 《Journal of Modern Physics》 2017年第4期668-746,共79页
Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D p... Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D projection. The origin of such rotation is the balance of the angular momenta of stars and that of positive and negative charged e-trino pairs, within a 3D &otimes;1D?void of the stellar object, the existence of which is based on conservation/parity laws in physics if one starts with homogeneous 5D universe. While the in-phase e-trino pairs are proposed to be responsible for the generation of angular momentum, the anti-phase but oppositely charge pairs necessarily produce currents. In the 5D to 4D projection, one space variable in the 5D manifold was compacted to zero in most other 5D theories (including theories of Kaluza-Klein and Einstein [3] [4]). We have demonstrated, using the Fermat’s Last Theorem [5], that for validity of gauge invariance at the 4D-5D boundary, the 4th space variable in the 5D manifold is mapped into two current rings at both magnetic poles as required by Perelman entropy mapping;these loops are the origin of the dipolar magnetic field. One conclusion we draw is that there is no gravitational singularity, and hence no black holes in the universe, a result strongly supported by the recent discovery of many stars with masses well greater than 100 solar mass [6] [7] [8], without trace of phenomena observed (such as strong gamma and X ray emissions), which are supposed to be associated with black holes. We analyze the properties of such loop currents on the 4D-5D boundary, where Maxwell equations are valid. We derive explicit expressions for the dipolar fields over the whole temperature range. We then compare our prediction with measured surface magnetic fields of many stars. Since there is coupling in distribution between the in-phase and anti-phase pairs of e-trinos, the generated mag-netic field is directly related to the angular momentum, leading to the result that the magnetic field can be expressible in terms of only the mechanical variables (mass M, radius R, rotation period P)of a star, as if Maxwell equations are “hidden”. An explanation for the occurrence of this “un-expected result” is provided in Section (7.6). Therefore we provide satisfactory answers to a number of “mysteries” of magnetism in astrophysics such as the “Magnetic Bode’s Relation/Law” [9] and the experimental finding that B-P graph in the log-log plot is linear. Moreover, we have developed a new method for studying the relations among the data (M, R, P) during stellar evolution. Ten groups of stellar objects, effectively over 2000 samples are used in various parts of the analysis. We also explain the emergence of huge magnetic field in very old stars like White Dwarfs in terms of formation of 2D Semion state on stellar surface and release of magnetic flux as magnetic storms upon changing the 2D state back to 3D structure. Moreover, we provide an explanation, on the ground of the 5D theory, for the detection of extremely weak fields in Venus and Mars and the asymmetric distribution of magnetic field on the Martian surface. We predict the equatorial fields B of the newly discovered Trappist-1 star and the 6 nearest planets. The log B?&minus;?log P graph for the 6 planets is linear and they satisfy the Magnetic Bode’s relation. Based on the above analysis, we have discovered several new laws of stellar magnetism, which are summarized in Section (7.6). 展开更多
关键词 5d Projection Theory Fermat’s Last Theorem Perelman’s Mappings Self-Rotation dipolar MaGNETIC FIELd of Stars LaWS of STELLaR Magnetism LaWS of STELLaR angular Momentum MaGNETIC Bode’s Law NON-EXISTENCE of Gravitational Singularity Semion State of atoms in STELLaR Surface MaGNETIC Storm Planetary MaGNETIC FIELd Maxwell Equations at 4d-5d Boundary MaGNETIC Fields of the Trappist-1 System
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Advancements and Innovations in Low-Temperature Hydrogen Electrochemical Conversion Devices Driven by 3D Printing Technology
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作者 Min Wang Xiuyue Wang +6 位作者 Enyang Sun Zhenye Kang Fan Gong Bin Hou Gaoqiang Yang Mingbo Wu Feng‑Yuan Zhang 《Nano-Micro Letters》 2026年第2期599-630,共32页
3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make i... 3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically,proton exchange membrane fuel cells,proton exchange membrane electrolyzer cells,anion exchange membrane electrolyzer cells,and alkaline electrolyzers—which demand finely structured components such as catalyst layers,gas diffusion layers,electrodes,porous transport layers,and bipolar plates.This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components.It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures.Finally,the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in nextgeneration low-temperature hydrogen energy systems. 展开更多
关键词 3d printing HYdROGEN Proton exchange membrane fuel cells Water electrolyzers
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Space solar cells with down-conversion quantum dots
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作者 CHEN Zijian ZHONG Yanhua +3 位作者 SI Meng WANG Jiayi LI Heng LI Wenhua 《Optoelectronics Letters》 2025年第7期413-418,共6页
Quantum dots(QDs)can modulate the solar spectrum through the down-conversion mechanism to better match the spectral response of solar cells.Following previous work,this paper first tested the response of QD solar cell... Quantum dots(QDs)can modulate the solar spectrum through the down-conversion mechanism to better match the spectral response of solar cells.Following previous work,this paper first tested the response of QD solar cells to specific monochromatic light,and found that QDs can effectively improve the photoelectric conversion efficiency(PCE)in the ultraviolet(UV)band by comparison.Then the photoelectric properties of the QD solar cells are tested under the air-mass 1.5(AM1.5)and air-mass 0(AM0)spectra.The experimental results show that because the absorption band of QDs is in the UV region,the space solar cells in the AM0 spectrum can obtain better PCE after coating QDs.The research results show the technical route of space solar cells with down-conversion mechanism,and put forward an important direction for the application of space solar photovoltaic(PV)technology,and have a good application prospect. 展开更多
关键词 photoelectric conversion efficiency photoelectric properties qd solar cells solar cellsfollowing down conversion quantum dots photoelectric conversion efficiency pce modulate solar spectrum quantum dots qds can
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Photocatalytic,electrocatalytic and photoelectrocatalytic conversion of methane to alcohol
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作者 Yu Huang Lei Zou +1 位作者 Yuan-Biao Huang Rong Cao 《Chinese Journal of Catalysis》 2025年第3期207-229,共23页
The conversion of the greenhouse gas methane to value-added chemicals such as alcohols is a promising technology to mitigate environmental issue and the energy crisis.Especially,the sustainable photocatalytic,electroc... The conversion of the greenhouse gas methane to value-added chemicals such as alcohols is a promising technology to mitigate environmental issue and the energy crisis.Especially,the sustainable photocatalytic,electrocatalytic and photoelectrocatalytic conversion of methane at ambient conditions is regarded as an alternative technology to replace with thermocatalysis.In this review,we summarize recent advances in photocatalytic,electrocatalytic and photoelectrocatalytic conversion of methane into alcohols.We firstly introduce the general principles of photocatalysis,electrocatalysis and photoelectrocatalysis.Then,we discuss the mechanism for selective activation of C-H bond and following oxygenation over metal,inorganic semiconductor,organic semiconductor,and heterojunction composite systems in the photocatalytic,electrocatalytic and photoelectrocatalytic methane oxidation in detail.Later,we present insights into the construction of effective photocatalyst,electrocatalyst and photoelectrocatalyst for methane conversion into alcohols from the perspective of band structures and active sites.Finally,the challenges and outlook for future designs of photocatalytic,electrocatalytic and photoelectrocatalytic methane oxidation systems are also proposed. 展开更多
关键词 Photocatalysis ELECTROCaTaLYSIS PHOTOELECTROCaTaLYSIS Methane conversion aLCOHOL
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