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High-energy-density lithium manganese iron phosphate for lithium-ion batteries:Progresses,challenges,and prospects
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作者 Bokun Zhang Xiaoyun Wang +5 位作者 Shuai Wang Yan Li Libo Chen Handong Jiao Zhijing Yu Jiguo Tu 《Journal of Energy Chemistry》 2025年第1期1-17,共17页
The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion batteries.Lithium manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered... The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion batteries.Lithium manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy density.Although LiMn_(x)Fe_(1-x)PO_(4)has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap density.This review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMn_(x)Fe_(1-x)PO_(4)to analyze reaction processes accurately and guide material preparation.Later,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMn_(x)Fe_(1-x)PO_(4),including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology design.Finally,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are anticipated.More importantly,it is expected to provide key insights into the development of high-performance and stable LiMn_(x)Fe_(1-x)PO_(4)materials,to achieve practical energy storage requirements. 展开更多
关键词 Lithiummanganese iron phosphate High energydensity LITHIUM-IONBATTERIES Reactionmechanism Tap density
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Enhancing sustainability in phosphate ore processing:Performance of frying oil as alternative flotation collector for carbonate removal 被引量:2
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作者 Asmae El-bahi Yassine Taha +2 位作者 Yassine Ait-Khouia Abdellatif Elghali Mostafa Benzaazoua 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期557-571,共15页
Recycling waste frying oils for the synthesis of flotation reagents presents a promising avenue for sustainable waste management.Moreover,it offers a cost-effective solution for crafting a specialized collector design... Recycling waste frying oils for the synthesis of flotation reagents presents a promising avenue for sustainable waste management.Moreover,it offers a cost-effective solution for crafting a specialized collector designed to efficiently remove carbonates and enhance phosphate enrichment in froth flotation processes.This study focuses on the synthesis of an anionic collector using the saponification reaction of a frying oil sample,subsequently applied to the flotation of calcite and dolomite.To elucidate the adsorption mechanisms of the frying oil collector(FrOC)and sodium oleate,a reference collector,on fluorapatite,calcite,dolomite,and quartz surfaces,comprehensive experiments were conducted,including zeta potential measurements and Fourier transform infrared spectroscopy.Results revealed diverse adsorption affinities of the molecules towards these minerals.To assess the practical performance of the collector,flotation tests were conducted using a natural phosphate ore mixture,employing a BoxBehnken experimental design.Notably,under optimized conditions(pH 9,1000 g/t of FrOC,3.5 min of conditioning,and 6 min of flotation),FrOC exhibited excellent performance,with calcite and dolomite recoveries exceeding 80%,while apatite recovery in the concentrate fraction remained below 10%.This work exemplifies both circular economy practices and the distinctive approach to sustainable mineral processing. 展开更多
关键词 Frying oils recycling phosphate beneficiation Flotation separation Green surfactants SUSTAINABILITY
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Modified electronic structure and enhanced hydroxyl adsorption make quaternary Pt-based nanosheets efficient anode electrocatalysts for formic acid-/alcohol-air fuel cells 被引量:1
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作者 Fengling Zhao Qiang Yuan +2 位作者 Siyang Nie Liang Wu Xun Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期142-150,共9页
Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet challenging.Herein,using visible light,a class of quaternary Pt_(1)... Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet challenging.Herein,using visible light,a class of quaternary Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)ultrathin nanosheets is fabricated and used as high-performance anode electrocatalysts for formic acid-/alcohol-air fuel cells.The modified electronic structure of Pt,enhanced hydroxyl adsorption,and abundant exterior defects afford Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C high intrinsic anodic electrocatalytic activity to boost the power densities of direct formic acid-/methanol-/ethanol-/ethylene glycol-/glycerol-air fuel cells,and the corresponding peak power density of Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C is respectively 129.7,142.3,105.4,124.3,and 128.0 mW cm^(-2),considerably outperforming Pt/C.Operando in situ Fourier transform infrared reflection spectroscopy reveals that formic acid oxidation on Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C occurs via a CO_(2)-free direct pathway.Density functional theory calculations show that the presence of Ag,Bi,and Te in Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)suppresses CO^(*)formation while optimizing dehydrogenation steps and synergistic effect and modified Pt effectively enhance H_(2)O dissociation to improve electrocatalytic performance.This synthesis strategy can be extended to 43 other types of ultrathin multimetallic nanosheets(from ternary to octonary nanosheets),and efficiently capture precious metals(i.e.,Pd,Pt,Rh,Ru,Au,and Ag)from different water sources. 展开更多
关键词 Pt-based nanosheets Modifiedelectronic structure Enhanced hydroxyl adsorption Formicacidand alcohol oxidation Direct liquid fuel cells
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Effect of safety valve types on the gas venting behavior and thermal runaway hazard severity of large-format prismatic lithium iron phosphate batteries 被引量:2
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作者 Zhuangzhuang Jia Yuanyuan Min +5 位作者 Peng Qin Wenxin Mei Xiangdong Meng Kaiqiang Jin Jinhua Sun Qingsong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期195-207,I0006,共14页
The safety valve is an important component to ensure the safe operation of lithium-ion batteries(LIBs).However,the effect of safety valve type on the thermal runaway(TR)and gas venting behavior of LIBs,as well as the ... The safety valve is an important component to ensure the safe operation of lithium-ion batteries(LIBs).However,the effect of safety valve type on the thermal runaway(TR)and gas venting behavior of LIBs,as well as the TR hazard severity of LIBs,are not known.In this paper,the TR and gas venting behavior of three 100 A h lithium iron phosphate(LFP)batteries with different safety valves are investigated under overheating.Compared to previous studies,the main contribution of this work is in studying and evaluating the effect of gas venting behavior and TR hazard severity of LFP batteries with three safety valve types.Two significant results are obtained:(Ⅰ)the safety valve type dominates over gas venting pressure of battery during safety venting,the maximum gas venting pressure of LFP batteries with a round safety valve is 3320 Pa,which is one order of magnitude higher than other batteries with oval or cavity safety valve;(Ⅱ)the LFP battery with oval safety valve has the lowest TR hazard as shown by the TR hazard assessment model based on gray-fuzzy analytic hierarchy process.This study reveals the effect of safety valve type on TR and gas venting,providing a clear direction for the safety valve design. 展开更多
关键词 Lithium iron phosphate battery Safety valve Thermal runaway Gas venting behavior Thermal runaway hazard severity Gray-fuzzy analytic hierarchy process
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Microanalyses of the hydroxyl-poly-calcium sodium phosphate coatings produced by ion beam assisted deposition
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作者 LIUZhong-Yang WANGChang-Xing 《Nuclear Science and Techniques》 SCIE CAS CSCD 2002年第4期205-210,共6页
Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar^+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,... Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar^+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity.No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were presented for CO3^-2,The calcium to phosphorous ratio of these catings in different IBAD conditions varied from 0.46 to 3.36. 展开更多
关键词 钛合金 磷酸钙涂层 Ar^+离子束
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Differential roles of C-3 and C-6 phosphate monoesters in affecting potato starch properties
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作者 Li Ding Andreas Blennow Yuyue Zhong 《Grain & Oil Science and Technology》 CAS 2024年第2期79-86,共8页
The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphor... The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphorylated maize starches with a similar range of amylose content(AC)as controls.The starch property results showed that a higher SPC is associated with lower turbidity,storage and loss modulus after storage,and water solubility,but higher swelling power(SP)and pasting viscosities.These findings suggested that SPC inhibited molecular rearrangement during storage and starch leaching during heating,and enhanced swelling and viscosities due to increased hydration and water uptake caused by the repulsion effect of phosphate groups and a less ordered crystalline structure.Increased SPC also resulted in lower resistant starch(RS)content in a native granular state but higher RS after retrogradation.Pearson correlations further indicated that SPC/C3P/C6P were positively correlated with peak(r^(2)=0.925,0.873 and 0.930,respectively),trough(r^(2)=0.994,0.968 and 0.988,respectively),and final viscosities(r^(2)=0.981,0.968 and 0.971,respectively).Notably,SPC,mainly C3P,exhibited a significantly positive correlation with SP(r^(2)=0.859)and setback viscosity(r^(2)=0.867),whereas SPC,mainly C6P,showed a weak positive correlation with RS after retrogradation(r^(2)=0.746).However,SPC had no significant correlations with water solubility,turbidity and rheology properties,which were more correlated with AC.These findings are helpful for the food industry to select potato starches with desired properties based on their contents of SPC,C3P,or C6P. 展开更多
关键词 Starch phosphate monoesters C-3 phosphate monoesters C-6 phosphate monoesters Physicochemical properties In vitro digestibility
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Introducing hydroxyl groups to tailor the d-band center of Ir atom through side anchoring for boosted ORR and HER
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作者 Qing Lv Meiping Li +3 位作者 Xiaodong Li Xingru Yan Zhufeng Hou Changshui Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期144-151,I0005,共9页
Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of... Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of hydrogen-substituted graphdiyne(HsGDY),and coordinated with OH as an Ir atomic catalyst(Ir_(1)-N-HsGDY).The electron structures,especially the d-band center of Ir atom,are optimized by these specific coordination atoms.Thus,the as-synthesized Ir_(1)-N-HsGDY exhibits excellent electrocatalytic performances for oxygen reduction and hydrogen evolution reactions in both acidic and alkaline media.Benefiting from the unique structure of HsGDY,IrN_(2)(OH)_(3) has been developed and demonstrated to act as the active site in these electrochemical reactions.All those indicate the fresh role of the sp-N in graphdiyne in producing a new anchor way and contributing to promote the electrocatalytic activity,showing a new strategy to design novel electrochemical catalysts. 展开更多
关键词 Oxygen reduction reaction D-band center Graphdiyne hydroxyl group ELECTROCATALYSIS
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Surface-neutralization engineered NiCo-LDH/phosphate hetero-sheets toward robust oxygen evolution reaction
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作者 Shunfa Zhou Yuxuan Liu +4 位作者 Jing Li Zhao Liu Jiawei Shi Liyuan Fan Weiwei Cai 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1151-1158,共8页
Developing highly active oxygen evolution reaction(OER)electrocatalysts with robust durability is essential in producing high-purity hydrogen through water electrolysis.Layered double hydroxide(LDH)based catalysts hav... Developing highly active oxygen evolution reaction(OER)electrocatalysts with robust durability is essential in producing high-purity hydrogen through water electrolysis.Layered double hydroxide(LDH)based catalysts have demonstrated efficient catalytic performance toward the relatively sluggish OER.By considering the promotion effect of phosphate(Pi)on proton transfer,herein,a facile phosphate acid(PA)surface-neutralization strategy is developed to in-situ construct NiCo-LDH/NiCoPi hetero-sheets toward OER catalysis.OER activity of NiCoLDH is significantly boosted due to the proton promotion effect and the electronic modulation effect of NiCoPi.As a result,the facilely prepared NiCo-LDH/NiCoPi catalyst displays superior OER catalytic activity with a low overpotential of 300 mV to deliver 100 mA cm^(-2)OER and a Tafel slope of 73 mV dec^(-1).Furthermore,no visible activity decay is detected after a 200-h continuous OER operation.The present work,therefore,provides a promising strategy to exploit robust OER electrocatalysts for commercial water electrolysers. 展开更多
关键词 Oxygen evolution reaction phosphatE Layered double hydroxide Hetero-sheets Stability
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In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites
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作者 Peng Zhang Fukuan Li +6 位作者 Mingming He Silu Huo Xueli Zhang Benqiang Cen Dezhi Fang Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期126-137,共12页
Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.Howev... Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.However,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and rates.Herein,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally demonstrated.The resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron transfer.The LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing electrodes.The superior phosphate removal performance originates from abundant active centers formed by the coupling of electricfield and capture sites.Besides,the stability and selectivity toward phosphate capture were maintained well even under comprehensive conditions.Moreover,a series of kinetics and isotherms models were employed to validate the electrosorption process.This work demonstrates a deep understanding and promotes a new level of phosphate electrosorption. 展开更多
关键词 Electro-assisted adsorption ELECTROSORPTION phosphate removal Active centers MOF-derived carbon
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Internal Polarization Field Induced Hydroxyl Spillover Effect for Industrial Water Splitting Electrolyzers
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作者 Jingyi Xie Fuli Wang +3 位作者 Yanan Zhou Yiwen Dong Yongming Chai Bin Dong 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期438-449,共12页
The formation of multiple oxygen intermediates supporting efficient oxygen evolution reaction(OER)are affinitive with hydroxyl adsorption.However,ability of the catalyst to capture hydroxyl and maintain the continuous... The formation of multiple oxygen intermediates supporting efficient oxygen evolution reaction(OER)are affinitive with hydroxyl adsorption.However,ability of the catalyst to capture hydroxyl and maintain the continuous supply at active sits remains a tremendous challenge.Herein,an affordable Ni2P/FeP2 heterostructure is presented to form the internal polarization field(IPF),arising hydroxyl spillover(HOSo)during OER.Facilitated by IPF,the oriented HOSo from FeP2 to Ni2P can activate the Ni site with a new hydroxyl transmission channel and build the optimized reaction path of oxygen intermediates for lower adsorption energy,boosting the OER activity(242 mV vs.RHE at 100 mA cm-2)for least 100 h.More interestingly,for the anion exchange membrane water electrolyzer(AEMWE)with low concentration electrolyte,the advantage of HOSo effect is significantly amplified,delivering 1 A cm^(-2)at a low cell voltage of 1.88 V with excellent stability for over 50 h. 展开更多
关键词 hydroxyl spillover effect Internal polarization field HETEROSTRUCTURE Oxygen reduction reaction Anion exchange membrane water electrolysis
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Non-flammable long chain phosphate ester based electrolyte via competitive solventized structures for high-performance lithium metal batteries
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作者 Li Liao Zhiqiang Han +16 位作者 Xuanjie Feng Pan Luo Jialin Song Yin Shen Xiaoshuang Luo Xinpeng Li Xuanzhong Wen Bo Yu Junchen Chen Bingshu Guo Mingshan Wang Yun Huang Hongmei Zhang Mengmeng Yin Jiangtao Liu Yuanhua Lin Xing Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期156-165,I0004,共11页
Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.... Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes. 展开更多
关键词 Non-flammable electrolyte Long chain phosphate ester Solvation structure Lithium metal batteries Battery safety
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可“湿碰湿”水性羟基丙烯酸分散体的性能及其应用研究
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作者 王元有 吴涛 周磊 《化学研究与应用》 北大核心 2025年第5期1428-1432,共5页
本研究主要对比了自制分散体与市售分散体在相同测试环境下对双组分聚氨酯涂膜基本物理性能以及耐水、耐酸碱等其他化学性能的影响。通过实验分析,发现两种分散体制备的聚氨酯涂膜在物理性能上差异不大,但在耐水、耐酸碱等化学性能上存... 本研究主要对比了自制分散体与市售分散体在相同测试环境下对双组分聚氨酯涂膜基本物理性能以及耐水、耐酸碱等其他化学性能的影响。通过实验分析,发现两种分散体制备的聚氨酯涂膜在物理性能上差异不大,但在耐水、耐酸碱等化学性能上存在一定差异。此外,还研究了在相同施工条件下,不同分散体聚氨酯涂料配制后的施工性能,如表干时间等。实验结果表明,自制分散体在“湿碰湿”聚氨酯涂料中的应用具有较好的性能表现,为羟基丙烯酸分散体在涂料行业中的应用提供了重要的数据支撑。本研究的发现对于优化聚氨酯涂料配方、提高涂料性能以及降低生产成本具有一定的指导意义。 展开更多
关键词 分散体 羟基丙烯酸 聚氨酯涂料 “湿碰湿”
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TBP与LEV混合物对铜绿微囊藻和斜生栅藻的联合毒性效应
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作者 沈洪艳 刘爱真 +4 位作者 杨雷 孙新宇 白玉玮 宁静 孙昊宇 《水生态学杂志》 北大核心 2025年第3期13-21,共9页
以铜绿微囊藻和斜生栅藻为模式生物,采用单一毒性试验、直接均分射线法进行二元联合毒性试验,运用独立作用模型(IA模型)判别联合毒性作用模式及评估强度,探究典型有机磷阻燃剂磷酸三丁酯(TBP)与抗生素左氧氟沙星(LEV)混合暴露对2种藻的... 以铜绿微囊藻和斜生栅藻为模式生物,采用单一毒性试验、直接均分射线法进行二元联合毒性试验,运用独立作用模型(IA模型)判别联合毒性作用模式及评估强度,探究典型有机磷阻燃剂磷酸三丁酯(TBP)与抗生素左氧氟沙星(LEV)混合暴露对2种藻的毒性效应。结果表明,TBP对铜绿微囊藻和斜生栅藻的EC_(50)分别为2.0×10^(-6)和6.7×10^(-5) mol/L;LEV对铜绿微囊藻和斜生栅藻的EC_(50)分别为3.4×10^(-7)和4.3×10^(-6) mol/L。TBP与LEV对铜绿微囊藻的单一毒性均大于斜生栅藻。基于均分射线设计的二元联合实验结果表明,随LEV占比降低,联合毒性减弱,且对铜绿微囊藻的毒性效应大于斜生栅藻。不同TBP和LEV配比下的二元混合体系对2种藻的联合毒性作用模式均具有浓度依赖性,表现为低浓度协同、高浓度拮抗。联合毒性作用强度随TBP和LEV浓度配比变化而变化,LEV浓度占比与其联合毒性作用呈正相关,TBP浓度占比与联合毒性作用呈负相关。TBP和LEV单一及混合体系对藻类生长均呈现出毒物兴奋(Hormesis)效应,即低浓度促进、高浓度抑制。研究结果可为有机磷阻燃剂和抗生素共存时的水生毒性和环境风险评估提供数据支撑。 展开更多
关键词 磷酸三丁酯 左氧氟沙星 铜绿微囊藻 斜生栅藻 联合毒性 毒物兴奋效应
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纤维特性对磷酸镁基免蒸压加气混凝土性能的影响
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作者 陈畅 丁学成 +1 位作者 酒少武 陈延信 《材料导报》 北大核心 2025年第10期94-100,共7页
免蒸压加气混凝土(NAAC)存在强度低和易开裂的问题。本工作采用磷酸镁水泥(MPC)作为基体制备磷酸镁基免蒸压加气混凝土(MPC-NAAC),通过添加聚丙烯纤维和玻璃纤维对其进行增强,系统研究了纤维长度和掺量对其物理、力学和耐水性能的影响;... 免蒸压加气混凝土(NAAC)存在强度低和易开裂的问题。本工作采用磷酸镁水泥(MPC)作为基体制备磷酸镁基免蒸压加气混凝土(MPC-NAAC),通过添加聚丙烯纤维和玻璃纤维对其进行增强,系统研究了纤维长度和掺量对其物理、力学和耐水性能的影响;并采用X射线衍射仪和扫描电镜分析其微观结构,揭示了纤维的增强机理。研究结果表明:纤维可以在降低MPC-NAAC干密度的同时提高其抗压和抗折强度,聚丙烯纤维和玻璃纤维的最佳长度均为9 mm,最佳掺量均为0.1%。此时,聚丙烯纤维增强的MPC-NAAC抗压和抗折强度较对照组分别提高了5.95%和16.46%;玻璃纤维增强的MPC-NAAC抗压和抗折强度较对照组分别提高了12.70%和11.39%。此外,纤维与基体之间的作用是物理作用,聚丙烯纤维表现出拔出破坏机制,玻璃纤维表现出断裂破坏机制。 展开更多
关键词 磷酸镁水泥 纤维长度 纤维掺量 力学性能 微观结构
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基于神经网络的深部磷矿岩体可爆性分级模型研究
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作者 柴修伟 李成镇 +3 位作者 盛益明 徐玉萍 徐亮 金胜利 《爆破》 北大核心 2025年第1期71-80,共10页
目前钻爆法仍是深部磷矿开拓掘进和回采的最高效方法。而磷矿钻爆法施工掘进水平长年维持在70~80 m/月,严重制约了掘进效率,因此对深部磷矿工作面开展矿岩体可爆性分级工作至关重要。以湖北宜昌某地下磷矿为研究背景,在现场进行了岩体... 目前钻爆法仍是深部磷矿开拓掘进和回采的最高效方法。而磷矿钻爆法施工掘进水平长年维持在70~80 m/月,严重制约了掘进效率,因此对深部磷矿工作面开展矿岩体可爆性分级工作至关重要。以湖北宜昌某地下磷矿为研究背景,在现场进行了岩体的纵波波速测试,开展了岩石密度、单轴抗压强度和抗拉强度等物理力学性质的测量,得到了白云质条带磷块岩、致密条带磷块岩、泥质条带磷块岩和含碳泥质白云岩4种岩石的密度、单轴抗压强度、抗拉强度和岩体完整性系数4项参数。通过调用Matlab神经网络工具箱,将岩石密度、单轴抗压强度、抗拉强度、岩体完整性系数作为输入,以可爆性等级作为输出,采用随机函数法产生大量的训练样本,构建了基于BP神经网络的可爆性评价模型,实现了深部磷矿岩体可爆性分级。分级结果为白云质条带磷块岩和泥质条带磷块岩为中等可爆,致密条带磷块岩和含碳泥质白云岩为难爆。根据分级结果,可对采场爆破参数进行优化,增强爆破效果,降低炸药单耗及矿石大块率,提高深部磷矿开采的安全性及经济效益。 展开更多
关键词 深部磷矿 岩体可爆性分级 随机函数 神经网络模型
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黄河河口适宜生态沙量研究
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作者 于守兵 《泥沙研究》 北大核心 2025年第2期44-50,共7页
黄河入海泥沙在塑造和维持河口生物栖息地和提供近岸海域磷酸盐方面具有重要的生态意义。20世纪80年代中期以来,河口来沙量锐减,行河流路淤积造陆速率放缓,而不行河流路附近海岸缺乏泥沙补给而持续蚀退。湿地面积萎缩导致生物多样性减... 黄河入海泥沙在塑造和维持河口生物栖息地和提供近岸海域磷酸盐方面具有重要的生态意义。20世纪80年代中期以来,河口来沙量锐减,行河流路淤积造陆速率放缓,而不行河流路附近海岸缺乏泥沙补给而持续蚀退。湿地面积萎缩导致生物多样性减少和原有生态系统结构功能发生变化。输入河口的磷主要以吸附在泥沙上的颗粒态存在,来沙量减少成为近岸海域N/P升高的重要因素。20世纪50年代末至80年代初,近岸海域磷酸盐浓度约0.50μmol/L可作为适宜参考水平。小浪底调水调沙运用后的2003—2006年黄河河口平均来沙量为2.4亿t/a,磷酸盐浓度、浮游植物物种和细胞量、叶绿素含量超过或接近20世纪80年代初期水平,可作为适宜的生态沙量。在此条件下现代三角洲基本保持陆地面积动态平衡。 展开更多
关键词 黄河河口 泥沙 生态 陆地面积 磷酸盐
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大剂量地塞米松磷酸钠注射液致急性重度肝损伤1例分析
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作者 王丽 唐金玲 +3 位作者 李翠红 谭飞龙 游丽娜 赵方允 《中国药物警戒》 2025年第5期589-591,共3页
目的 探讨地塞米松磷酸钠注射液致急性重度肝损伤的不良反应,为临床安全用药提供参考。方法 对1例原发免疫性血小板减少患者使用大剂量地塞米松磷酸钠注射液后出现急性重度肝损伤的病例,结合相关文献进行分析。结果 根据患者的临床表现... 目的 探讨地塞米松磷酸钠注射液致急性重度肝损伤的不良反应,为临床安全用药提供参考。方法 对1例原发免疫性血小板减少患者使用大剂量地塞米松磷酸钠注射液后出现急性重度肝损伤的病例,结合相关文献进行分析。结果 根据患者的临床表现、实验室检查及用药时间关联性,大剂量地塞米松磷酸钠注射液致急性重度肝损伤为很可能,后停用地塞米松磷酸钠注射液,更换为醋酸泼尼松片减量使用,肝损伤逐渐好转。但目前对糖皮质激素引起肝损伤的机制尚不清楚,需进一步研究明确。结论 临床在使用地塞米松磷酸钠注射液时要加强其不良反应监护,特别是大剂量使用时,应警惕肝损伤的不良反应。 展开更多
关键词 地塞米松磷酸钠 注射液 糖皮质激素 剂量 药品不良反应 肝损伤
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生物炭基菌剂的制备及应用效果研究
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作者 刘月芹 马泉 +1 位作者 陈风 刘啸尘 《西安工程大学学报》 2025年第1期26-32,共7页
为了增强磷细菌菌剂的应用效果,通过添加不同量的玉米秸秆生物炭(corn stover biochar,CSB)与溶磷菌(phosphate-solubilizing bacteria,PSB)菌液制备溶磷菌生物炭基菌剂,以OD_(600)和有效活菌数为指标分析生物炭基菌剂的制备条件。通过... 为了增强磷细菌菌剂的应用效果,通过添加不同量的玉米秸秆生物炭(corn stover biochar,CSB)与溶磷菌(phosphate-solubilizing bacteria,PSB)菌液制备溶磷菌生物炭基菌剂,以OD_(600)和有效活菌数为指标分析生物炭基菌剂的制备条件。通过盆栽实验,考察生物炭基菌剂对小麦生长性能和土壤理化性质的影响。结果表明:当生物炭的添加量为0.16%时,制备的生物炭基菌剂的OD 600显著提高,有效活菌数高达8.37 CFU/pL,比CK1(无CSB)组提高了3.3倍。生物炭基菌剂T组(CSB+PSB)能有效促进小麦的生长,施加菌剂四周后,株高、叶绿素含量及根系活力比CK1组分别提高了(10.25±0.62)%、(67.69±4.21)%和(49.58±3.73)%。同时,生物炭基菌剂还有效改善了土壤性能,土壤速效氮、土壤速效磷、S-CAT以及脲酶酶活,比CK1组分别提高了(31.81±2.25)%、(50.71±4.58)%、(30.89±1.43)%和(44.26±3.84)%。单独施加生物炭的CK2(CSB)组的各项指标稍高于CK1组。添加定量的生物炭对小麦的生长及土壤性能的改善效果明显,但以生物炭为载体制备的溶磷菌生物炭基菌剂则能更有效地提高土壤肥力进而增强小麦的促生性能。 展开更多
关键词 生物炭 溶磷菌 生物炭基菌剂 土壤性能 促生性能
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水镁石基磷酸镁胶凝材料的碳排放概率评价方法
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作者 李悦 刘效龙 罗晓 《建材世界》 2025年第2期7-11,共5页
采用概率生命周期评价法,量化水镁石磷酸镁胶凝材料(BMPC)碳排放强度并分析其不确定性。结果表明,BMPC碳排放低于传统磷酸镁胶凝材料(MPC),以水镁石为镁质原料时其碳排放强度平均0.523 kg CO_(2)e/kg,当矿物掺合料的比例超过10%时可降至... 采用概率生命周期评价法,量化水镁石磷酸镁胶凝材料(BMPC)碳排放强度并分析其不确定性。结果表明,BMPC碳排放低于传统磷酸镁胶凝材料(MPC),以水镁石为镁质原料时其碳排放强度平均0.523 kg CO_(2)e/kg,当矿物掺合料的比例超过10%时可降至0.50 kg CO_(2)e/kg以下。此外,可溶性磷酸盐是影响BMPC碳排放的关键因素,且是主要的碳排放来源。 展开更多
关键词 碳排放 水镁石磷酸镁胶凝材料 概率生命周期评估 不确定性分析
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基于FTIR的环氧化植物油开环过程中指标监测研究
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作者 李文龙 叶子寒 +4 位作者 王琰 孙悦文 毕艳兰 彭丹 李军 《中国油脂》 北大核心 2025年第3期44-49,共6页
为满足工业化生产过程中对植物油基多元醇性能的在线快速检测,以环氧大豆油为原料,合成了57个不同羟基含量的植物油基多元醇[羟基值(KOH)94.1~229.4 mg/g、环氧值0~3.68%、聚合羟基值(KOH)85.1~207.5 mg/g],采用傅里叶红外光谱(FTIR)仪... 为满足工业化生产过程中对植物油基多元醇性能的在线快速检测,以环氧大豆油为原料,合成了57个不同羟基含量的植物油基多元醇[羟基值(KOH)94.1~229.4 mg/g、环氧值0~3.68%、聚合羟基值(KOH)85.1~207.5 mg/g],采用傅里叶红外光谱(FTIR)仪对样品进行扫描,以43个样品作为建模集,14个样品作为验证集,建立基于FTIR的不同植物油基多元醇的羟基值、环氧值和聚合羟基值的定量模型。考察了归一化、二阶导数、标准正态变量变换、多元散射校正、正交散射校正(OSC)光谱预处理方法对定量模型的影响,确定了最佳建模波段,并比较了主成分回归(PCR)、偏最小二乘法(PLS)和支持向量机回归(SVR)3种建模方法的建模效果。结果表明:使用OSC预处理方法得到的羟基值、环氧值和聚合羟基值PLS模型的校正集均方根误差,相比于原始数据PLS模型分别降低12.2%、12.2%和13.0%;羟基值、环氧值和聚合羟基值建模的最佳波段分别为500~4 000 cm^(-1)、800~900 cm^(-1)、1 000~1 200 cm^(-1);羟基值和聚合羟基值模型的最佳建模方法为PLS,环氧值模型的最佳建模方法为PLS和PCR,羟基值、环氧值和聚合羟基值最优模型的决定系数(R^(2))均达到0.98以上。综上,采用FTIR技术在线快速检测植物油基多元醇羟基值、环氧值和聚合羟基值的方法是可行的。 展开更多
关键词 FTIR 植物油基多元醇 羟基值 环氧值 聚合羟基值 化学计量学
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