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Modeling and analysis of a novel oxygen production approach with full-spectrum solar energy for the lunar human base
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作者 Wei Zhu Maobin Hu 《中国科学技术大学学报》 北大核心 2025年第2期2-17,1,I0001,共18页
Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temper... Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temperature carbon dioxide electrolysis,utilizing the full solar spectrum.The optimal oxygen production rates under different solid oxide electrolysis cell inlet temperatures T_(e),ultraviolet(UV)separation wavelengths λ_(2),infrared(IR)separation wavelengths,and photovoltaic cell materials were explored.The results indicate that the inlet temperature of the solid oxide electrolysis cell should be as high as possible so that more carbon dioxide can be converted into carbon monoxide and oxygen.Furthermore,when the ultraviolet separation wavelength is approximately 385 nm,the proportion of solar energy allocated to the photoreaction and electrolysis cell is optimal,and the oxygen production rate is highest at 2.754×10^(-4) mol/s.Moreover,the infrared separation wavelength should be increased as much as possible within the allowable range to increase the amount of solar radiation allocated to the electrolysis cell to improve the rate of oxygen generation.In addition,copper indium gallium selenide(CIGS)has a relatively large separation wavelength,which can result in a high oxygen production rate of 3.560×10^(-4) mol/s.The proposed integrated oxygen production method can provide a feasible solution for supplying oxygen to a lunar human base. 展开更多
关键词 lunar oxygen production full-spectrum solar energy photovoltaic and photon-enhanced thermionic emission electrolysis of carbon dioxide photothermal synergistic reaction solid oxide electrolysis cell
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Production and trade trend of oils and oilseeds in BRICS countries
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作者 ZHANG Hong 《中国油脂》 CAS CSCD 北大核心 2024年第8期1-10,共10页
In order to promote agricultural production and trade cooperation among BRICS countries,and ensure the security and stability of the oils and oilseeds industrial and supply chains in China and the world,the production... In order to promote agricultural production and trade cooperation among BRICS countries,and ensure the security and stability of the oils and oilseeds industrial and supply chains in China and the world,the production,consumption,trade trend,and cooperation potential of oils and oilseeds in BRICS countries were expounded,and relevant policy recommendations were put forward.Most of the BRICS countries are major agricultural producers,and they are also important agricultural product consumption markets in the world.In 2023/2024,the production and consumption of oilseeds in BRICS countries account for nearly half of the world's total;the production of vegetable oils exceeds a quarter of the world's total,and the consumption of vegetable oils accounts for 40%of the world's total.In 2023/2024,the import and export volume of oilseeds exceeds half of the world's total;vegetable oil imports account for 40%of the world's total,and exports account for about one tenth of the world's total.China's imports of oilseeds and oils from BRICS countries account for 68%and 29%of its global imports in 2023,respectively.BRICS countries are rich in agricultural land resources,have great potential for oils and oilseeds production,obvious complementary advantages in trade structure,and huge space for future cooperation.It is suggested that Brazil should be included in the"Belt and Road"co-construction category to promote the continuous deepening of agricultural cooperation between China and Brazil.It is suggested to explore regional agricultural trade agreements among BRICS countries,promote currency settlement and exchange among BRICS countries,and enhance the facilitation and stability of BRICS trade.It is suggested that China should increase its investment in BRICS countries and export advanced technology and management experience to benefit local agricultural development and achieve a mutually beneficial and win-win situation. 展开更多
关键词 BRICS countries oils and oilseeds production and consumption trade trend agricultural potential
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In-situ photodeposition of co-catalyst Ni_(2)P on CdS for photocatalytic conversion of ethanol for synergistic hydrogen production
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作者 LIU Yiming MIAO Jingjing +2 位作者 ZHANG Wanggang WEI Aili WANG Jian 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第11期1629-1640,共12页
In this study,Ni_(2)P/CdS composites were constructed by depositing non-precious metal co-catalyst Ni_(2)P on a one-dimensional network of CdS using a simple in-situ photodeposition method.The prepared photocatalysts ... In this study,Ni_(2)P/CdS composites were constructed by depositing non-precious metal co-catalyst Ni_(2)P on a one-dimensional network of CdS using a simple in-situ photodeposition method.The prepared photocatalysts promoted the decomposition of ethanol into high-value-added products while generating hydrogen.The composite photoanodes loaded with the Ni_(2)P co-catalysts showed significantly higher ethanol conversion and hydrogen production in the visible light region,which was almost three times higher than that of pure CdS.The main products of photocatalytic ethanol production are acetaldehyde(AA)and 2,3-butanediol(2,3-BDA).Compared with CdS,the selectivity of the composite photocatalysts for converting ethanol to acetaldehyde was significantly improved(62% to 78%).Characterization of the prepared photocatalysts confirmed that the loading of Ni_(2)P co-catalysts on CdS not only broadened the optical region of the catalysts for trapping light but also effectively promoted the separation and transfer of charge carriers,which significantly improved the photocatalytic efficiency of ethanol conversion and hydrogen production in the catalysts.It has been proven through Electron Paramagnetic Resonance testing that loading a Ni_(2)P co-catalyst on CdS is beneficial for the adsorption of hydroxyethyl radicals(*CH(OH)CH_(3)),thereby further improving the selectivity of acetaldehyde.This study plays an important role in the rational design of composite catalyst structures and the introduction of co-catalysts to improve catalyst performance,promote green chemistry,advocate a low-carbon society,and promote sustainable development. 展开更多
关键词 photocatalysis Ni_(2)P/CdS ethanol conversion hydrogen production
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Raney Ni as a high-performance catalyst for the hydrolysis of ammonia borane to produce hydrogen
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作者 YANG Tianxuan WU Meixia +6 位作者 WANG Junli CHEN Ning TANG Changqiang LI Jiang SHANG Jianpeng GUO Yong LI Zuopeng 《燃料化学学报(中英文)》 北大核心 2025年第4期555-564,共10页
Ammonia borane(AB)has received much attention as an environmentally friendly,non-toxic,room temperature stable hydrogen storage material with high hydrogen content of 19.6%.However,its hydrolysis for hydrogen producti... Ammonia borane(AB)has received much attention as an environmentally friendly,non-toxic,room temperature stable hydrogen storage material with high hydrogen content of 19.6%.However,its hydrolysis for hydrogen production at room-temperature is kinetically slow and requires precious metal catalysts.In this work,it is found that the prepared Raney Ni W-r treated with high concentration of NaOH(6.25 mol/L)at 110℃exhibited excellent catalytic performance for AB hydrolysis at room temperature.The Raney Ni W-r can promote the AB complete hydrolysis within 60 s under basic condition at small sized trials,even higher than that of the 20%Pt/C catalyst.Its apparent activation energy at room temperature is only 26.6 kJ/mol and the turnover frequency(TOF)value is as high as 51.42 min-1.Owing to its high density and magnetic properties,the catalyst is very easy for magnetic separation.Furthermore,possible mechanism of the hydrolytic reaction of AB based on experimental results is proposed.As a well-established industrial catalyst,Raney Ni has been prepared on a large scale at low cost.This study provides a promising pathway for the large-scale preparation of low-cost and recyclable catalysts for AB hydrolysis. 展开更多
关键词 ammonia borane HYDROLYSIS Raney Ni hydrogen production
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第8期I0028-I0028,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects. 展开更多
关键词 Food Science Animal Products
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Current status of sea cucumber aquaculture and the research progress on skincare benefits in China
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作者 Chujie Zhao Liqing Wu +3 位作者 Qiuxing He Zheng Yang Lvyangguang Ye Lihong Yuan 《日用化学工业(中英文)》 北大核心 2025年第2期225-234,共10页
The sea cucumber is a highly esteemed source of nourishment,recognized as one of the“Eight Treasures of the Sea.”The bioactive compounds derived from sea cucumbers exhibit diverse physiological activities,including ... The sea cucumber is a highly esteemed source of nourishment,recognized as one of the“Eight Treasures of the Sea.”The bioactive compounds derived from sea cucumbers exhibit diverse physiological activities,including anti-tumor,antioxidant,anti-coagulation,anti-viral,anti-fatigue,immune enhancement,cognitive improvement,and metabolic regulation.Notably,within the skincare sector,these compounds demonstrate significant anti-aging,moisturizing,whitening,wrinkle reduction,repair and inhibition of melanin production properties.This article assesses the current state of sea cucumber aquaculture in China and the utilization of its bioactive ingredients in skincare formulations.The objective is to furnish additional raw materials and semi-finished products for China’s skincare and pharmaceutical industries,to advance the integration of sea cucumber bioactive components within these sectors,and to invigorate the rapid development of the tropical sea cucumber breeding industry. 展开更多
关键词 sea cucumber active ingredients skin care products BREEDING tropical sea cucumber
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第11期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects. 展开更多
关键词 animal origin foods EGGS animal offals food materials MEAT MILK food science animal products issn e issn edible insects
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Detonation product analysis and the paradoxical performance mechanism of TKX-50:High detonation velocity with low metal acceleration
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作者 Kaiyuan Tan Yaqi Zhao +10 位作者 Qin Liu Lixiao Hao Yushi Wen Chunliang Ji Sha Yang Haoxu Wang Luchuan Jia Jiahui Liu Zhuoping Duan Yong Han Fenglei Huang 《Defence Technology(防务技术)》 2025年第4期255-266,共12页
This study investigates the paradoxical detonation behavior of TKX-50,a nitrogen-rich energetic material,exhibiting higher detonation velocities but lower metal acceleration ability compared to HMX.Through experimenta... This study investigates the paradoxical detonation behavior of TKX-50,a nitrogen-rich energetic material,exhibiting higher detonation velocities but lower metal acceleration ability compared to HMX.Through experimental measurements and theoretical calculations,we propose a novel three-factor competition mechanism to explain this phenomenon.TKX-50-based PBX formulations achieved detonation velocities up to 9100 m/s,surpassing HMX-based counterparts.However,cylinder expansion tests revealed a 15%reduction in metal acceleration ability.Thermochemical measurements showed lower detonation heat for TKX-50(4900 J/g)versus HMX(5645 J/g).Our mechanism involves:(1)compositional effects prevailing at high pressures;(2)Energy release becoming essential as pressure drops;(3)Pressure-dependent product composition evolution functioning at low pressure.VLW code calculations unveiled a"crossover"in Hugoniot curves,lending support to this mechanism.This study furnishes a new framework for comprehending the performance of nitrogen-rich energetic materials,with significant implications for the design and optimization of future high-energy density materials. 展开更多
关键词 TKX-50 Nitrogen-rich explosives Detonation velocity Metal acceleration Detonation product
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Microstructure and mechanical properties of welds of AZ31B magnesium alloy produced by different gas tungsten arc welding variants
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作者 S.Srinivasan R.Ravi Bharath +1 位作者 A.Atrens P.Bala Srinivasan 《Defence Technology(防务技术)》 2025年第2期98-110,共13页
This work aimed to(i)understand conventional and pulse gas tungsten arc welding(GTAW)of AZ31B,and(ii)explore high frequency welding(100 Hz-1500 Hz).GTA welding with alternating current(AC)and direct current electrode ... This work aimed to(i)understand conventional and pulse gas tungsten arc welding(GTAW)of AZ31B,and(ii)explore high frequency welding(100 Hz-1500 Hz).GTA welding with alternating current(AC)and direct current electrode positive(DCEP)polarities yielded crack-free partial penetration welds for6 mm thick AZ31B alloy sheet.Welding under direct current electrode negative(DCEN)polarity with identical parameters as that for AC and DCEP resulted in full penetration welds that had microcracks.Defect-free full-penetration welds could be accomplished with pulse GTA welding using DCEN polarity at a pulse frequency of 1 Hz with a pulse duration ratio of 1:1.The resultant DCEN P 1:1 weld metal had a microstructure finer than the conventional DCEN weld.Welds produced with pulse duration ratios of 1:2and 1:4 lacked penetration but had a much finer microstructures because of the lower heat input.The arc constriction by the high frequency pulsing in the Activ Arc■-High frequency(AA-HF)mode welding was responsible for deeper penetration.Welds produced under DCEN pulsing and AA-HF conditions had hardness higher than conventional DCEN,DCEP and AC GTA welds,attributed to the finer microstructure.AA-HF GTA welding produced defect free deeper penetration welds with good microstructural features/mechanical properties and also gave an advantage of 50%enhanced productivity when welded at1500 Hz. 展开更多
关键词 AZ31B alloy Pulse GTAW High frequency Microstructure Mechanical properties PRODUCTIVITY
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第10期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第20期I0021-I0021,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第12期I0022-I0022,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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基于UPLC-Q-TOF/MS同步检测液态乳中4-甲基咪唑、糠氨酸和羧甲基赖氨酸
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作者 徐文龙 谢一嘉 +5 位作者 潘洋 廖丽娟 黄敏 杨寅玺 吴永泰 李冰 《中国乳品工业》 北大核心 2025年第7期67-73,共7页
乳品加工中美拉德反应的有害产物会对人体健康造成潜在威胁。建立高效、准确的美拉德反应有害产物检测方法对于乳制品品质控制具有重要意义。文章建立了一种超高效液相色谱-超高分辨率四极杆飞行时间质谱(UPLC-Q-TOF/MS)测定乳制品中4-... 乳品加工中美拉德反应的有害产物会对人体健康造成潜在威胁。建立高效、准确的美拉德反应有害产物检测方法对于乳制品品质控制具有重要意义。文章建立了一种超高效液相色谱-超高分辨率四极杆飞行时间质谱(UPLC-Q-TOF/MS)测定乳制品中4-甲基咪唑(4-methylimidazole,4-MEI)、糠氨酸和羧甲基赖氨酸(Nε-(carboxymethyl)lysine,CML)含量的同步检测方法。结果表明,牛奶最佳盐酸水解条件为温度110℃,时间6 h,HCl浓度10.6 mol/L。方法学验证表明,3种目标分析物在相应浓度范围内线性良好(R^(2)>0.99),检出限和定量限在1~3 ng/mL和3~10 ng/mL范围内。平均回收率范围为69.50%~79.01%,相对标准偏差(RSD)均小于5%。利用该方法检测市售的6种液态乳制品,结果显示高温灭菌乳4-MEI含量最高,超高温瞬时杀菌乳糠氨酸含量最高,巴氏杀菌乳CML含量最高。综上,该方法适用于液态乳制品中4-MEI、糠氨酸和CML的同步快速检测。 展开更多
关键词 乳制品 同步检测 4-甲基咪唑 糠氨酸 羧甲基赖氨酸
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Robust microwave catalytic decomposition of H_(2)S into H_(2) and S at low temperature over Mo_(2)C@CeO_(2) catalysts
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作者 SUN Hongyang CHEN Jun +2 位作者 TU Cong ZHOU Jicheng XU Wentao 《燃料化学学报(中英文)》 北大核心 2025年第9期1399-1415,I0027,I0028,共19页
The new technology of direct decomposition of H_(2)S into high value-added H_(2) and S,as an alternative to the Claus process in industry,is an ideal route that can not only deal with toxic and abundant H_(2)S waste g... The new technology of direct decomposition of H_(2)S into high value-added H_(2) and S,as an alternative to the Claus process in industry,is an ideal route that can not only deal with toxic and abundant H_(2)S waste gas but also recover clean energy H_(2),which has significant socio-economic and ecological advantages.However,the highly effective decomposition of H_(2)S at low temperatures is still a great challenge,because of the stringent thermodynamic equilibrium constraints(only 20% even at high temperature of 1010℃).Conventional microwave catalysts exhibit unsatisfactory performance at low temperatures(below 600℃).Herein,Mo_(2)C@CeO_(2) catalysts with a core-shell structure were successfully developed for robust microwave catalytic decomposition of H_(2)S at low temperatures.Two carbon precursors,para-phenylenediamine(Mo_(2)C-p)and meta-phenylenediamine(Mo_(2)C-m),were employed to tailor Mo_(2)C configurations.Remarkably,the H_(2)S conversion of Mo_(2)C-p@CeO_(2) catalyst at a low temperature of 550℃ is as high as 92.1%,which is much higher than the H_(2)S equilibrium conversion under the conventional thermal conditions(2.6% at 550℃).To our knowledge,this represents the most active catalyst for microwave catalytic decomposition of H_(2)S at low temperature of 550℃.Notably,Mo_(2)C-p demonstrated superior intrinsic activity(84%)compared to Mo_(2)C-m(6.4%),with XPS analysis revealing that its enhanced performance stems from a higher concentration of Mo_(2+)active sites.This work presents a substitute approach for the efficient utilization of H_(2)S waste gas and opens up a novel avenue for the rational design of microwave catalysts for microwave catalytic reaction at low-temperature. 展开更多
关键词 direct decomposition of H_(2)S microwave catalysis low temperature microwave selective catalytic effect Mo_(x)C@CeO_(2) H_(2)production
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集成化学链制氢的CO_(2)零排放SOFC/GT/ORC混合动力系统性能
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作者 佟勇婧 王军 +6 位作者 池立勋 程思昱 段立强 张汉飞 王秋实 王浩博 黄龑 《热力发电》 北大核心 2025年第5期44-53,共10页
提出一种新型集成化学链制氢的CO_(2)零排放固体氧化物燃料电池/燃气轮机/有机朗肯循环混合动力系统,在实现高效发电的同时,高效分离捕集CO_(2)。系统以甲烷为燃料,通过化学链反应产生氢气进入燃料电池,避免了电池内部积碳现象发生,电... 提出一种新型集成化学链制氢的CO_(2)零排放固体氧化物燃料电池/燃气轮机/有机朗肯循环混合动力系统,在实现高效发电的同时,高效分离捕集CO_(2)。系统以甲烷为燃料,通过化学链反应产生氢气进入燃料电池,避免了电池内部积碳现象发生,电池阳极出口回路至化学链,燃料反应器出口与电池阴极出口气体进入燃气轮机做功,排气余热被有机朗肯循环系统回收利用,进一步提高系统效率;并建立了系统模型并进行热力学性能分析,得到系统性能随燃料流量、燃料利用率、电池工作温度及系统工作压力的变化规律。结果表明:系统综合能源利用效率可达74.10%以上,电效率可达62.42%以上,?效率达到57.73%;敏感性分析表明,系统工作压力达到7×10^(5)Pa时,系统性能达到最优。 展开更多
关键词 固体氧化物燃料电池 化学链制氢 分布式发电系统 热力学性能
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CoFe_(2)O_(4)@MoS_(2)活化PMS降解环丙沙星的产物及毒性分析 被引量:1
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作者 王杰 马梦杰 +1 位作者 谢鹏飞 章慧娟 《中国环境科学》 北大核心 2025年第5期2865-2874,共10页
利用实验室制备的CoFe_(2)O_(4)@MoS_(2)活化过一硫酸氢盐(PMS)降解水中的环丙沙星(CIP),SEM及XRD的表征结果证明了CoFe_(2)O_(4)@MoS_(2)的成功制备.降解结果表明,CoFe_(2)O_(4)@MoS_(2)/PMS体系中CIP的去除率在120min达到74.38%,高于... 利用实验室制备的CoFe_(2)O_(4)@MoS_(2)活化过一硫酸氢盐(PMS)降解水中的环丙沙星(CIP),SEM及XRD的表征结果证明了CoFe_(2)O_(4)@MoS_(2)的成功制备.降解结果表明,CoFe_(2)O_(4)@MoS_(2)/PMS体系中CIP的去除率在120min达到74.38%,高于单独的CoFe_(2)O_(4)@MoS_(2)以及PMS体系之和,证实了CoFe_(2)O_(4)@MoS_(2)对PMS的活化能力.淬灭实验结果表明CoFe_(2)O_(4)@MoS_(2)/PMS体系中的主要的氧化活性物种为OH、SO_(4)^(-)以及^(1)O_(2),且SO_(4)^(-)和^(1)O_(2)对CIP的降解起主要作用.通过密度泛函理论并结合HPLC分析,得到8种可能的中间产物并提出了CIP可能的两种降解路径.T.E.S.T程序对降解产物的环境风险的评价预测结果显示,和母体相比,大部分产物的急性毒性降低、致突变性减弱、生物累积性和发育毒性降低,生态毒性明显降低.此外,4次循环后CoFe_(2)O_(4)@MoS_(2)/PMS体系对CIP的去除率仍能达到60.04%,且XRD结果显示反应前后催化剂的晶体结构变化不明显,说明了催化剂的高效稳定性. 展开更多
关键词 Cofe_(2)O_(4)@MoS_(2) 活化过一硫酸氢盐(PMS) 环丙沙星 降解产物 毒性分析
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基于UPLC-QTOF-MS/MS的四种土壤中三氟嘧磺草胺及其五种转化物的不确定度分析
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作者 谢雨君 彭晓民 +4 位作者 龚玄彧 吕孜 单洁 欧阳柳荟 周雯雯 《生物灾害科学》 2025年第2期229-234,共6页
【目的】聚焦三氟嘧磺草胺这一受广泛关注的广谱选择性除草剂,旨在系统研究其在不同土壤类型中的环境行为,精确评估测定过程中的不确定度来源,为三氟嘧磺草胺的精准测定提供技术支撑,提升农药残留分析的可靠性。【方法】运用超高效液相... 【目的】聚焦三氟嘧磺草胺这一受广泛关注的广谱选择性除草剂,旨在系统研究其在不同土壤类型中的环境行为,精确评估测定过程中的不确定度来源,为三氟嘧磺草胺的精准测定提供技术支撑,提升农药残留分析的可靠性。【方法】运用超高效液相色谱-四极杆飞行时间串联质谱(UPLC-QTOF-MS/MS)技术,测定水稻土、红壤、黄壤和紫色土四种土壤类型中三氟嘧磺草胺及其五种转化物的残留量;依据《测量不确定度评定与表示》标准,对标准溶液配制、样品前处理、加标回收率及仪器检测等环节进行不确定度量化分析。【结果】成功测定出四种土壤类型中三氟嘧磺草胺及其五种转化物的残留量;量化分析得出当目标化合物残留量为0.0019~0.9954μg/kg时,其扩展不确定度为0.1309~0.2409μg/kg;明确主要影响因素依次为加标回收率(贡献率28%)、样品前处理(贡献率24%)和标准溶液配制(贡献率20%)。【结论】实现了对三氟嘧磺草胺在不同土壤中残留量及测定不确定度的系统分析,为该除草剂残留量的精确测定提供了关键技术支持,有力提升了农药残留分析的可靠性。 展开更多
关键词 不确定度 超高效液相色谱-四极杆飞行时间串联质谱(UPLC-QTof-MS/MS) 三氟嘧磺草胺 土壤 转化物
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基于MALDI-TOF核酸质谱的11种牛源病毒检测方法的建立
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作者 帅江冰 张泽林 +6 位作者 宋士琦 韩笑 曾若雪 陈吴健 郭悠然 郭惠民 张晓峰 《中国预防兽医学报》 北大核心 2025年第1期39-47,共9页
为建立能高效同步鉴定牛腺病毒3型(BAV-3)、牛细小病毒1、2和3型(BPV-1、BPV-2、BPV-3)、牛病毒性腹泻病毒(BVDV)、狂犬病毒(RV)、呼肠孤病毒3型(REO-3)、牛副流感病毒3型(BPIV-3)、蓝舌病毒(BTV)、牛呼吸道合胞体病毒(BRSV)以及牛多瘤... 为建立能高效同步鉴定牛腺病毒3型(BAV-3)、牛细小病毒1、2和3型(BPV-1、BPV-2、BPV-3)、牛病毒性腹泻病毒(BVDV)、狂犬病毒(RV)、呼肠孤病毒3型(REO-3)、牛副流感病毒3型(BPIV-3)、蓝舌病毒(BTV)、牛呼吸道合胞体病毒(BRSV)以及牛多瘤病毒(BPyV)等牛源病毒的基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)高通量多目标检测技术,本研究根据上述11种病原基因组的高保守区,分别设计多重PCR引物及对应的单碱基延伸探针,采用方阵法优化反应体系后初步建立牛源病毒的MALDI-TOF核酸质谱检测体系。利用该方法以靶标病毒质粒标准品混合物及非靶标病毒核酸为模板进行特异性试验,利用50拷贝/µL、25拷贝/µL、12.5拷贝/µL、6.3拷贝/µL、3.1拷贝/µL、1.6拷贝/µL靶标病毒核酸质粒标准品进行敏感性试验,利用106拷贝/µL、104拷贝/µL、102拷贝/µL靶标病毒核酸重组质粒标准品于同一时间和不同时间进行了稳定性试验。特异性试验结果显示,该方法仅对11种靶标病毒产生阳性信号峰,而与其他病原体无交叉反应,表明该方法特异性较强。敏感性试验结果通过probit模型进行概率回归检测,结果显示每种病毒最低检测限在8.69拷贝/µL~38.04拷贝/µL(99%概率),表明该方法敏感性较高。重复性试验结果显示,体系中每种靶标在高、中、低质粒浓度时的批内及批间重复性试验结果的符合率均达100%,表明该方法的稳定性较高。利用该MALDI-TOF核酸质谱检测体系对血液类生物制品及临床样品进行检测,同时采用各病毒的荧光定量PCR(qPCR)检测,结果显示130份样品中总计检出58份阳性,其中包括43份BPV-3、33份BPV-2、16份BPyV、6份BVDV阳性,总阳性率分别为44.0%、33.1%、25.4%、12.3%和4.6%,与各病毒qPCR结果的符合率均达100%。本研究基于MALDI-TOF核酸质谱技术首次建立了11种牛病毒的多重检测方法,为牛源病毒的快速检测及相关生物制品安全控制提供了一种新的检测技术。 展开更多
关键词 MALDI-Tof核酸质谱 牛血液制品 病毒
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MALDI-TOF MS 在乳制品快速检测中的研究进展
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作者 黄宝莹 李沅镁 +2 位作者 严家俊 张娟 周臣清 《中国乳品工业》 北大核心 2025年第4期62-66,共5页
基质辅助激光解析电离飞行时间质谱(MALDI-TOF MS)作为一种高灵敏、高速质谱分析技术,在乳制品快速检测中应用广泛。文章深入介绍了MALDI-TOF MS技术原理、发展历程、分类、优点和局限性,详细阐述了其在乳制品领域的应用进展,展望了MALD... 基质辅助激光解析电离飞行时间质谱(MALDI-TOF MS)作为一种高灵敏、高速质谱分析技术,在乳制品快速检测中应用广泛。文章深入介绍了MALDI-TOF MS技术原理、发展历程、分类、优点和局限性,详细阐述了其在乳制品领域的应用进展,展望了MALDI-TOF MS技术在乳制品领域未来的发展趋势,为乳制品质量控制和快速检测提供了全面视角,有助于推动该技术在乳制品领域的广泛应用和进一步发展。 展开更多
关键词 基质辅助激光解析电离飞行时间质谱 乳制品 快速检测 应用
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基于改进COF-YOLO v8n的油茶果静态与动态检测计数方法 被引量:16
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作者 王金鹏 何萌 +1 位作者 甄乾广 周宏平 《农业机械学报》 EI CAS CSCD 北大核心 2024年第4期193-203,共11页
针对自然环境下油茶果存在严重遮挡、近景色、小目标等现象,使用YOLO网络存在检测精度低、漏检现象严重等问题,提出对YOLO v8n网络进行改进。首先使用MPDIOU作为YOLO v8n的损失函数,有效解决因为果实重叠导致的漏检问题;其次调整网络,... 针对自然环境下油茶果存在严重遮挡、近景色、小目标等现象,使用YOLO网络存在检测精度低、漏检现象严重等问题,提出对YOLO v8n网络进行改进。首先使用MPDIOU作为YOLO v8n的损失函数,有效解决因为果实重叠导致的漏检问题;其次调整网络,向其中加入小目标检测层,使网络能够关注小目标油茶以及被树叶遮挡的油茶;最后使用SCConv作为特征提取网络,既能兼顾检测精度又能兼顾检测速度。改进COF-YOLO v8n网络精确率、召回率、平均精度均值分别达到97.7%、97%、99%,比未改进的YOLO v8n分别提高3.2、4.8、2.4个百分点,其中严重遮挡情况下油茶检测精确率、召回率、平均精度均值分别达到95.9%、95%、98.5%,分别比YOLO v8n提高4.0、9.1、4.6个百分点。因此改进后COF-YOLO v8n网络能够明显提高油茶在严重遮挡、近景色、小目标均存在情况下的识别精度,减小油茶的漏检。此外,模型能够实现动、静态输入条件下油茶果计数。动态计数借鉴DeepSORT算法的多目标跟踪思想,将改进后COF-YOLO v8n的识别输出作为DeepSORT的输入,实现油茶果实的追踪计数。所得改进模型具有很好的鲁棒性,且模型简单可以嵌入到边缘设备中,不仅可用于指导自动化采收,还可用于果园产量估计,为果园物流分配提供可靠借鉴。 展开更多
关键词 油茶果 机器视觉 Cof-YOLO v8n 计数 产量估计
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