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The effect of Ti and Zr content on the structure,mechanics and energy-release characteristics of Ti—Zr—Ta alloys
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作者 Jia-yu Meng Jing-zhi He +4 位作者 Bin Zhang Jin Chen Shun Li Dun Niu Yu Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期343-350,共8页
Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-elem... Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-element Ti-Zr-Ta alloys with good casting performance were studied.The microstructure of the Ti_(x)ZrTa alloys gradually change from BCC+HCP to single BCC structure with the increase of Ti.While the Ti_(2)Zr_(y)Ta alloys was still uniform and single BCC structure with the increase of Zr.The evolution of microstructure and composition then greatly affect the mechanical properties and energy-release characteristics of Ti-Zr-Ta alloys.The synergistic effect of dual phase structure increases the fracture strain of Ti_(x)ZrTa(x=0.2,0.5)with the Ti content decreases,while the fracture strain of Ti_(x)ZrTa(x=2.0,3.0,4.0)gradually increase with the Ti content increases caused by the annihilation of the obstacles for dislocation movement.And as Zr content increases,the fracture strain of Ti_(2)Zr_(y)Ta alloys decrease,then the oxidation reaction rate and fragmentation degree gradually increase.The higher oxidation rate and the lager exposed oxidation area jointly leads the higher releasing energy efficiency of Ti_(x)ZrTa alloys with low Ti content and Ti_(2)Zr_(y)Ta alloys with high Zr content. 展开更多
关键词 Energetic structural materials Ti-Zr-Ta Multi-element alloy Energy release characteristics
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Nutrient Release Characteristics of Vinyl Chloride-Vinyl acetate Copolymers Coated SlowRelease Nitrogen Fertilizer and Its Effect on Soil Mineral Nitrogen
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作者 马洪波 许仙菊 +3 位作者 宁运旺 汪吉东 张辉 张永春 《Agricultural Science & Technology》 CAS 2014年第3期412-416,421,共6页
[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetat... [Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited. 展开更多
关键词 Water immersion method Pot experiment method Vinyl chloride-vinyl acetate copolymer Nutrient release characteristics Soil mineral nitrogen
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Study on energy release characteristics of reactive material casings under explosive loading 被引量:6
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作者 Ning Du Wei Xiong +3 位作者 Tao Wang Xian-feng Zhang Hai-hua Chen Meng-ting Tan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1791-1803,共13页
Reactive Materials(RMs),a new material with structural and energy release characteristics under shockinduced chemical reactions,are promising in extensive applications in national defense and military fields.They can ... Reactive Materials(RMs),a new material with structural and energy release characteristics under shockinduced chemical reactions,are promising in extensive applications in national defense and military fields.They can increase the lethality of warheads due to their dual functionality.This paper focuses on the energy release characteristics of RM casings prepared by alloy melting and casting process under explosive loading.Explosion experiments of RM and conventional 2A12 aluminum alloy casings were conducted in free field to capture the explosive fireballs,temperature distribution,peak overpressure of the air shock wave and the fracture morphology of fragments of reactive material(RM)warhead casings by using high-speed camera,infrared thermal imager temperature and peak overpressure testing and scanning electron microscope.Results showed that an increase of both the fireball temperature and air shock wave were observed in all RM casings compared to conventional 2A12 aluminum ally casings.The RM casings can improve the peak overpressure of the air shock wave under explosion loading,though the results are different with different charge ratios.According to the energy release characteristics of the RM,increasing the thickness of RM casings will increase the peak overpressure of the near-field air shock wave,while reducing the thickness will increase the peak overpressure of the far-field air shock wave. 展开更多
关键词 Reactive materials Explosive loading Shock-induced chemical reaction Energy release characteristics FRAGMENTATION
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Energy release characteristics of PTFE/Al/TiH_2 reactive jet with different TiH_2 content
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作者 Chunlan Jiang Jingbo Zhang +2 位作者 Rong Hu Liang Mao Ming Li 《Defence Technology(防务技术)》 SCIE EI CAS 2024年第9期168-176,共9页
Titanium hydride(TiH_(2)), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types ... Titanium hydride(TiH_(2)), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH_(2) reactive liners with different TiH_(2) content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH_(2) reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time,pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH_(2) jet initially increase and then decrease with increasing TiH_(2) content. When the TiH_(2) content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH_(2) content increased from 0% to 30%. Finally,combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH_(2) on energy release of the reactive jet is expounded. 展开更多
关键词 PTFE/Al/TiH_2 Reactive materials Shaped charge Impact energy release characteristics
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Gas release characteristics during carbonization of iron coke hot briquette and influence of heating rate
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作者 Zi-yu Wang Dong Han +5 位作者 Zheng-gen Liu Man-sheng Chu Yong-jie Zhang Li-feng Zhang Ji-wei Bao Ming-yu Wang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2023年第11期2163-2172,共10页
The release characteristics of CH_(4),H_(2),CO and CO_(2) from iron coke hot briquette(ICHB)during carbonization were studied.The results show that compared with briquette without iron ore,Fe_(3)O_(4) can inhibit the ... The release characteristics of CH_(4),H_(2),CO and CO_(2) from iron coke hot briquette(ICHB)during carbonization were studied.The results show that compared with briquette without iron ore,Fe_(3)O_(4) can inhibit the release rate of H2 and promote the production of CO and CO_(2).In addition,when the heating rate increases from 3 to 7℃/min,the release rates of CH4 and H2 increase,while the release rates of CO and CO_(2) first increase and then decrease.The carbonization process of ICHB was segmented,and corresponding kinetic analysis was carried out.The results show that the activation energy of StageⅡand StageⅣis higher in the carbonization process of ICHB,and the active pyrolysis of coal and the reduction of iron ore occur in these two stages.In addition,the effect of heating rate on the kinetic parameters of ICHB carbonization process was investigated.It was found that when the heating rate increased,the reaction activation energy of StageⅣdecreased first and then increased,which was consistent with the release law of CO and CO_(2).The analysis showed that the increase in heating rate leads to more reactions at higher temperatures,resulting in an increase in the release rate of some gases.In addition,thermal hysteresis can also cause some processes to fail to fully react at the end of heating.It is also found that the apparent activation energy and preexponential factor have kinetic compensation effect during the car-bonization of ICHB. 展开更多
关键词 Iron coke hot briquette CARBONIZATION Gas release characteristic Heating rate Kinetics
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Study on Characteristics of Decomposition and Nutrients Release of Two Kinds of Green Manure Crops 被引量:2
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作者 董浩 朱国梁 +2 位作者 夏光利 毕军 曹卫东 《Agricultural Science & Technology》 CAS 2016年第8期1875-1878,共4页
With nylon mesh bags, the decomposition and nutrients release characteristics of two kinds of green manure crops, February orchid (Orychophragmus violaceus) and Hair Vetch (Vicia villosa Roth), were investigated i... With nylon mesh bags, the decomposition and nutrients release characteristics of two kinds of green manure crops, February orchid (Orychophragmus violaceus) and Hair Vetch (Vicia villosa Roth), were investigated in this study. The results showed that these two kinds of green manure crops were decomposed rapidly in the first 14 days, and then decomposed slowly. After 80 days of incubation, the decomposition rates of February orchid and Hair Vetch were 66.92% and 63.12%, respectively. Different nutrients had different release rates from the green manures. Nitrogen (N) and potassium (K) were released rapidly in the initial 7 days, and phosphorus (P) was released steadily in the 80 days of incubation. In the two kinds of green manures, the release rates all ranked as K's〉N's〉P's. The release rates of nutrients, especially P (P〈0.05), of February orchid were higher than those of Hair Vetch. 展开更多
关键词 February orchid Hair Vetch Decomposition characteristics Nutrient release characteristics
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Initial carbon release characteristics, mechanisms and denitrification performance of a novel slow release carbon source 被引量:10
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作者 Congyu Li Haiyan Wang +6 位作者 Guokai Yan Weiyang Dong Zhaosheng Chu Huan Wang Yang Chang Yu Ling Yanjie Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第8期32-45,共14页
External carbon source addition is one of the effective methods for the treatment of wastewater with low carbon to nitrogen ratio(C/N). Compared with fast-release liquid carbon sources, slow-release solid carbon sourc... External carbon source addition is one of the effective methods for the treatment of wastewater with low carbon to nitrogen ratio(C/N). Compared with fast-release liquid carbon sources, slow-release solid carbon sources are more suitable for the denitrification process. A novel slow-release solid carbon source(corncob-polyvinyl alcohol sodium alginatepoly-caprolactone, i.e. CPSP) was prepared using corn cob(CC) and poly-caprolactone with polyvinyl alcohol sodium alginate as hybrid scaffold. The physical properties and carbon release characteristics of CPSP and three other carbon sources were compared. CPSP had stable framework and good carbon release performance, which followed the second order release equation. The formic acid, acetic acid, propionic acid and butyric acid released from CPSP accounted for 8.27% ± 1.66 %, 56.48% ± 3.71 %, 18.46% ± 2.69% and 16.79% ± 3.02% of the total released acids respectively. The start-up period of CPSP was shorter than that of the other carbon sources in denitrification experiment, and no COD pollution was observed in the start-up phase(25–72 h) and stable phase(73–240 hr). The composition and structure of the dissolved organic compounds released by CPSP and other carbon sources were analyzed by UV-Vis absorption spectroscopy and three-dimensional fluorescence spectroscopy,which indicated that CPSP was more suitable for denitrification than the other studied carbon sources. 展开更多
关键词 Novel slow-release carbon source Carbon release characteristics DENITRIFICATION Dissolved organic matter Corn cob
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The Production of Organic-Inorganic Compound Film-Coated Urea and the Characteristics of Its Nutrient Release 被引量:6
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作者 ZOU Hong-tao, WANG Yao-sheng, SONG Hao-wen, HAN Yan-yu, YU Na, ZHANG Yu-ling, DANG Xiu-li, HUANG Yi and ZHANG Yu-long College of Land and Environmental Sciences, Shenyang Agricultural University/Liaoning Key Laboratory of Agricultural Resources and Environment/Northeast Key Laboratory of Soil and Environment, Ministry of Agriculture, Shenyang 110161, P.R.China 《Agricultural Sciences in China》 CSCD 2009年第6期703-708,共6页
The effect of different concentrations of natural macromolecular compound on the characteristics of nutrient release in the membrane materials of organic-inorganic compound film-coated urea was discussed, and the opti... The effect of different concentrations of natural macromolecular compound on the characteristics of nutrient release in the membrane materials of organic-inorganic compound film-coated urea was discussed, and the optimal concentrations for better nutrient release was proposed. The characteristics of nutrient release of film-coated urea were evaluated by soil column leaching experiment. Organic-inorganic compound film-coated urea showed good characteristics of nutrient release, which could be well simulated by Logistic curve. The two parameters in this curve, a and r, can be used to present nutrient release of film-coated urea, and followed the order of B 〉 C 〉 A and C 〈 B 〈 A, respectively, indicating that the release was stronger with the increasing concentration of natural macromolecular compound in the membrane, which implied better controllability of nutrient release. The concentration of 5% of natural macromolecular compound showed better characteristic of nutrient release and can be utilized as a membrane material combined with inorganic mineral powders to develop film-coated slow-release fertilizer. 展开更多
关键词 organic-inorganic compound film-coated urea nutrient release characteristics
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Influence of quick release valve on braking performance and coupler force of heavy haul train 被引量:1
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作者 Wei Wei Yuan Zhang +1 位作者 Jun Zhang Xubao Zhao 《Railway Engineering Science》 2023年第2期153-161,共9页
We establish a simulation model based on the theory of air flow to analyze the accelerated release effect of the quick release valve inside the air brake control valve.In addition, the combined simulation system of tr... We establish a simulation model based on the theory of air flow to analyze the accelerated release effect of the quick release valve inside the air brake control valve.In addition, the combined simulation system of train air brake system and longitudinal train dynamics is used to analyze how the parameters of the quick release valve in the 120/120–1 brake control valve affect the propagation characteristics of the train brake pipe pressure wave, the release action range of the accelerated brake, and the longitudinal coupler force for a 20,000-ton heavy haul train on the section of the Datong–Qinhuangdao Railway. The results show that the quick release valve can effectively accelerate the rising speed of the train brake pipe pressure during the initial release, as the accelerated release effect is evident before the train brake pipe pressure reaches582 k Pa. The quick release valve can effectively accelerate the release of the rear cars, reducing the longitudinal coupler force impact due to time delay of the release process. The quick release valve can effectively reduce the tensile coupler force in the train by as much as 20% in certain cases. 展开更多
关键词 Brake system release characteristics Quick release valve Coupler force Heavy haul train
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Relationships between Potential Risk of Hazardous Material Releases and Socio-Economic Demographic Characteristics Using Geospatial Analysis
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作者 Seong Nam Hwang Venu Srivastav Kannegalla 《Journal of Geoscience and Environment Protection》 2021年第7期62-85,共24页
The problem investigated in this research is about the potential risk of technological hazards, which poses a perilous threat to humankind and the environment. Rapid urbanization has been increasing the population den... The problem investigated in this research is about the potential risk of technological hazards, which poses a perilous threat to humankind and the environment. Rapid urbanization has been increasing the population density in an area, elevating the risk of exposure to technological disasters. Therefore, it is necessary to detect the areas with higher chemical risk to spread awareness about the potential risk zones and reduce actual damage and casualties resulting from the hazardous substance events. The basic design of the study utilizes geospatial analysis to map the TRI (Toxics Release Inventory) facilities in the communities of Texas to establish a relationship between potential </span><span style="font-family:Verdana;">hazardous material release zones and the human population at risk. The</span><span style="font-family:Verdana;"> study identified the vulnerable counties as well as investigated how those risk areas are related to race/ethnicity, income and education. The research would contribute to the policymakers acting on the hazard situation and keep them better prepared for</span><span style="color:red;"> </span><span style="font-family:Verdana;">chemical hazards. In addition, it would help the residents and emergency managers to better understand the circumstance to mitigate the consequences as well as increase their awareness to be ready for the uncertainties in the hotspots involved in high risk of the hazards. 展开更多
关键词 Environmental Hazard Risk GIS DISASTER Hazard Mitigation Emergency Management Toxics release Inventory (TRI) Facilities and Socioeconomic Demographic characteristics
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Effects of different types of slow-and controlled-release fertilizers on rice yield 被引量:4
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作者 WU Qiong WANG Yu-hui +6 位作者 DING Yan-feng TAO Wei-ke GAO Shen LI Quan-xin LI Wei-wei LIU Zheng-hui LI Gang-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第6期1503-1514,共12页
This experiment explored the effects of single application of seven types of slow-and controlled-release fertilizers on rice yield and various population characteristics.Based on a study of the nitrogen(N)release char... This experiment explored the effects of single application of seven types of slow-and controlled-release fertilizers on rice yield and various population characteristics.Based on a study of the nitrogen(N)release characteristics of these fertilizers,pot experiments were conducted in 2018 and 2019 with split fertilization(CK,urea applied split equally at basal and panicle initiation stages,respectively)as control,which assessed the effects on SPAD value,yield and yield components,dynamic changes of rice tillers and dry matter accumulation.The results showed that the N release characteristics of different types of slow-and controlled-release fertilizers were significantly different.Polymer-coated urea(PCU)showed a controlledrelease mode and provided sustained release throughout the whole growth stages.Sulfur-coated urea(SCU)exhibited a slow-release mode,providing insufficient release at the middle and late stages.Urease inhibitor urea(AHA)and ureaformaldehyde(UF)yielded a rapid-release mode,with an explosive N release at the early stage and no release at the middle and late stages.These results showed that PCU delayed the peak seedling stage.Compared with CK,dry matter accumulation and SPAD showed no significant differences,and due to the continuous release of N throughout the growth stages,rice yield,spikelets per panicle,seed setting rate,and 1000-grain weight were all increased.Owing to the lack of N supply at the late stage and the low number of spikelets,SCU led to a reduction of rice yield,which is nevertheless not statistically significant.AHA and UF were susceptible to environmental factors and had varying effects on rice yield.The results of this experiment indicated that given a fixed amount of N applied in a pot,the stronger the N supply capacity and the longer the effective duration time of the fertilizer,the higher the dry matter accumulation at the late growth stage,and the higher the rice yield. 展开更多
关键词 slow-and controlled-release fertilizers fertilizer types rice yield fertilizer release characteristics
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General Situation of Green Manure Germplasm Resources in China and Research Progress on Decomposition Characteristics and Fertility Improvement of Green Manures 被引量:2
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作者 Zhongyi LI Hongqin TANG Caihui WEI 《Agricultural Biotechnology》 CAS 2018年第4期147-152,共6页
As a kind of biological fertilizer sources, green manure can improve soil fertility and the quality of agricultural products. This paper introduced the germplasm resource of green manures in the major provinces in Chi... As a kind of biological fertilizer sources, green manure can improve soil fertility and the quality of agricultural products. This paper introduced the germplasm resource of green manures in the major provinces in China, mainly summarized the characteristics of decomposition and nutrients release of returning green manures to soils, as well as the influence on soil fertility and succeeding crops, with the aim to provide references for rational utilization of green manures and the scientific management of farmland nutrients. 展开更多
关键词 Green manure Decomposition characteristics Nutrients release characteristics Fertility improvement
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Analysis of NO_X Emission Characteristics of Pulverized Coal Combustion in Different Atmosphere
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作者 刘汉涛 尉庆国 苏铁熊 《Journal of Measurement Science and Instrumentation》 CAS 2011年第2期201-204,共4页
Researches on the NOx emission characteristics of HT (Huangtai coal), LC(Laicheng) coal are carried out in different atmosphere. The results show that the NOx emission time is postponed in O2/N2 atmosphere mixed w... Researches on the NOx emission characteristics of HT (Huangtai coal), LC(Laicheng) coal are carried out in different atmosphere. The results show that the NOx emission time is postponed in O2/N2 atmosphere mixed with CO. The releasing times of volatile nitrogen and char nitrogen approach, the amount of NOx reduces. In high 02 concentration atmosphere mixed with CO2, the nitrogen releasing times cane ahead of time, NOx congregate in the beginning of the combustion. On the contrary, nitrogen releases separately, and the amount of NOx reduces greatly. 展开更多
关键词 fuel nitrogen releasing characteristics pulverized coal NOx
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