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Spatial-temporal characteristics of the coupling coordination of social security and economic development in China during 2002–2018 被引量:3
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作者 Qiong li Yang Zhao +1 位作者 songlin li Lanlan Zhang 《Regional Sustainability》 2021年第2期116-129,共14页
Clarifying the relationship between social security and economic development is helpful to realize the sustainable social security system and the stable function of sustainable economic development.In this paper,the e... Clarifying the relationship between social security and economic development is helpful to realize the sustainable social security system and the stable function of sustainable economic development.In this paper,the entropy method,coupling coordination degree,standard deviation ellipse model,and spatial autocorrelation were used to study the spatial-temporal characteristics of coupling coordination of social security and economic development in China from 2002 to 2018.The results indicate that the relationship between social security and economic development in China has been gradually strengthened in the process of mutual adaptation and common development.The benign interaction between the two was unstable,though the coupling coordination degree gradually transitioned to the primary coupling coordination type.Besides,from a spatial perspective,first,the coupling coordination degree of social security and economic development in China contracted in the east-west and north-south directions,and the coupling coordination clustered in the central region in this period;second,the coupling coordination degree generally presented a positive spatial autocorrelation,and regions with similar coupling coordination degrees were in a state of agglomeration;finally,the hot spots clumped together to form a continuous area in the eastern coastal area while the cold spots expanded toward the northwest and northeast.Furthermore,the random distribution areas exhibited a trend of contraction. 展开更多
关键词 Social security Economic development Coupling coordination degree Gravity center Moran index
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Different Frequency Synchronization Theory and Its Frequency Measurement Practice Teaching Innovation Based on Lissajous Figure Method 被引量:1
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作者 Xin Geng songlin li +2 位作者 Guangming Huang Baoqiang Du Jianhua Chen 《Journal of Beijing Institute of Technology》 EI CAS 2018年第2期198-205,共8页
According to the requirement of multi-parameter time and frequency measurement without frequency normalization,a different frequency synchronization theory is proposed based on Lissajous figure method and the variatio... According to the requirement of multi-parameter time and frequency measurement without frequency normalization,a different frequency synchronization theory is proposed based on Lissajous figure method and the variation lawof Lissajous figure which are used in practice teaching of frequency measurement. The theory can achieve high-precision transmission and comparison of time and frequency and precise locking and tracking of phase and frequency,improve the level of scientific research on time and frequency for postgraduate,and promote practice teaching innovation of time frequency measurement for undergraduate. Utilizing the ratio of horizontal and vertical inflection point of the Lissajous figure,the nominal frequency of the measured signal is precisely calculated.The frequency deviation between the measured frequency and its nominal frequency can be obtained by combining the turning cycle of the Lissajous figure. By observing the phase relationship between the frequency standard signal and the measured signal,the accurate measurement of the frequency is implemented. Experimental results showthat the direct measurement and comparison better than the 10-11 order of magnitude with common frequency source can be finished between any signal frequencies.The frequency measurement method based on the theory has the advantage of simple operation,quick measurement speed,small error,lownoise and high measurement precision. It plays an important role in time synchronization,communications,metrology,scientific research,educational technology practice and equipment and other fields. 展开更多
关键词 Lissajous figure different frequency synchronization frequency measurement
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物理化学全线上教学的策略与实践 被引量:22
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作者 冯霞 刘俊吉 +6 位作者 李松林 孙艳 朱荣娇 朱莉娜 陈丽 王玉新 张小涛 《大学化学》 CAS 2020年第5期92-97,共6页
受新型冠状病毒肺炎疫情影响,学校的教学活动都转到线上进行。本文以天津大学“物理化学”课程为例,介绍了全线上教学的策略、过程设计与实施效果。通过进一步丰富线上教学资源、完善教学手段、实行全过程精细化管理,使得物理化学这门... 受新型冠状病毒肺炎疫情影响,学校的教学活动都转到线上进行。本文以天津大学“物理化学”课程为例,介绍了全线上教学的策略、过程设计与实施效果。通过进一步丰富线上教学资源、完善教学手段、实行全过程精细化管理,使得物理化学这门原本不太适合完全线上学习的课程,取得了满意的教学效果。学习过程中,学生的主体地位和教师的主导作用得以完美体现,获得的教学经验对于未来课程教学有很好的借鉴意义。 展开更多
关键词 新型冠状病毒肺炎疫情 全线上教学 物理化学 以学生为中心
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预乳化半连续法聚丙烯酸酯核壳乳液的制备与性能 被引量:6
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作者 韦双颖 张红 +6 位作者 桂成胜 张彦华 毕晓柯 余华 张宇 李松林 王亚宁 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第5期35-40,共6页
以甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为主单体,丙烯酸(AA)和丙烯酸羟丙酯(HPMA)为功能性单体,采用预乳化、半连续法种子乳液聚合方法合成了一种硬核软壳聚丙烯酸酯乳液。文中研究了核壳质量比、核和壳中软硬单体BA/MMA质量比对乳液... 以甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为主单体,丙烯酸(AA)和丙烯酸羟丙酯(HPMA)为功能性单体,采用预乳化、半连续法种子乳液聚合方法合成了一种硬核软壳聚丙烯酸酯乳液。文中研究了核壳质量比、核和壳中软硬单体BA/MMA质量比对乳液及涂膜性能的影响。通过激光粒度仪、透射电镜、差示扫描量热分析、动态力学分析等手段对乳液粒径及表面形貌、涂膜的玻璃化转变温度、力学性能进行了分析,并对漆膜的硬度、附着力、吸水率等进行了检测,结果表明,核壳质量比为5∶5、核中m(BA)∶m(MMA)为0∶50、壳中m(BA)∶m(MMA)为24∶26时,储存模量可达到3500 MPa,漆膜硬度为2H,附着力为1;乳胶粒有明显的核壳结构,粒径在100 nm左右。 展开更多
关键词 预乳化 半连续法 核壳结构 聚丙烯酸酯乳液
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Fault zone structures of northern and southern portions of the main central fault generated by the 2008 Wenchuan earthquake using fault zone trapped waves 被引量:15
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作者 songlin li Xiaoling Lai +1 位作者 Zhixiang Yao Qing Yang 《Earthquake Science》 CSCD 2009年第4期417-424,共8页
The rupture process of the May 12, 2008 Ms8.0 Wenchuan earthquake was very complex. To study the rupture zones generated by this earthquake, four dense temporary seismic arrays across the two surface breaking traces o... The rupture process of the May 12, 2008 Ms8.0 Wenchuan earthquake was very complex. To study the rupture zones generated by this earthquake, four dense temporary seismic arrays across the two surface breaking traces of the main-shock were deployed in July and recorded a great amount of aftershocks. This paper focuses on the data interpretation of two arrays across the central main fault, the northern array line 1 and southern array line 3. The fault zone trapped waves recorded by the two arrays were used to study the structure of the central main fault and the difference between the northern and southern portions. The results show that the widths of the rupture zone are about 170-200 m and 200-230 m for northern and southern portions respectively. And the corresponding dip angles are 80° and 70°. The seismic velocity inside the fracture zone is about one half of the host rock. By comparison, the northern portion of the rupture zone is slightly narrower and steeper than the southern portion. Besides these differences, one more interesting and important difference is the positions of the rupture zone with respect to surface breaking traces. At the northern portion, the rupture zone is centered at the surface breaking trace, while at the southern portion it is not but is shifted to the northwest. This difference reflects the difference of rupture behaviors between two portions of the central main fault. The width of the rupture zone is smaller than that of MS.1 Kunlun earthquake though these two earthquakes have almost the same magnitudes. Multiple ruptures may be one factor to cause the narrower rupture zone. 展开更多
关键词 Wenchuan earthquake seismic rupture zone fault zone trapped waves
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Facile fabrication of MoP nanodots embedded in porous carbon as excellent anode material for potassium-ion batteries 被引量:5
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作者 Zhanheng Yan Zhongyuan Huang +5 位作者 Haihui Zhou Xinxin Yang songlin li Wenlong Zhang Fei Wang Yafei Kuang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期571-578,共8页
Molybdenum phosphide(MoP),owing to its abundant reserve and high theoretical capacity,is regarded as a promising anode material for potassium-ion batteries.However,it still suffers from the problems of acute volume ex... Molybdenum phosphide(MoP),owing to its abundant reserve and high theoretical capacity,is regarded as a promising anode material for potassium-ion batteries.However,it still suffers from the problems of acute volume expansion and weak diffusion kinetics.This study reports a simple method to synthesize a composite of molybdenum phosphide and porous carbon(MoP@PC)through simple mixing and annealing treatment.In the MoP@PC,lots of MoP nanodots with an average diameter of about 4 nm uniformly embedded in the petal-like porous carbon.The MoP@PC shows reversible capacities of 330 mAh g^(-1) at100 mA g^(-1) after 100 cycles,and ultra-long cycling stability with a capacity of 240 mAh g^(-1) after 1000 cycles at 1 A g^(-1) and 161 mAh g^(-1) after 1000 cycles at 5 A g^(-1).The structure of MoP@PC after charging-discharging cycles is also investigated by high resolution transmission electron microscope(HRTEM)and the result shows that MoP can still maintain the nanodot morphology without any agglomeration after 1000 cycles at 5 A g^(-1).The storage mechanism of potassium ions was studied as well,which reveals that MoP and potassium ion have a conversion reaction. 展开更多
关键词 MOP NANODOT Anode Potassium-ion batteries
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3D hierarchical microspheres constructed by ultrathin MoS2-C nanosheets as high-performance anode material for sodium-ion batteries 被引量:3
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作者 Wenlong Zhang Haihui Zhou +6 位作者 Zhongyuan Huang songlin li Chuqing Wang Huanxin li Zhanheng Yan Teng Hou Yafei Kuang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第10期307-315,共9页
MoS2/C composites are considered to have great application potential in sodium-ion batteries(SIBs).It is a challenging and meaningful subject that developing high-performance anode materials via combining MoS2 and car... MoS2/C composites are considered to have great application potential in sodium-ion batteries(SIBs).It is a challenging and meaningful subject that developing high-performance anode materials via combining MoS2 and carbon effectively to give free rein to their advantages in sodium ion storage.In this work,a novel MoS2-C material was designed by using cellulose nanocrystals(CNCs)as low-cost and green carbon source.3 D hierarchical microspheres(200-250 nm)constructed by ultrathin MoS2-C nanosheets were synthesized by synchronizing the pre-carbonization of CNCs with the formation of MoS2 in hydrothermal reaction and subsequent pyrolysis process.It is found that the ultrathin MoS2-C nanosheets were composed of CNCs-derived short-range ordered carbon and few-layered MoS2.Benefiting from the unique structure and robust combination of MoS2 and CNCs-derived carbon,the ultrathin MoS2-C nanosheets composite was proved to have excellent cycling stability and superior rate performance in sodium-ion half-cell test and have high first reversible specific capacity of 397.9 m Ah/g in full-cell test.This work provides a significant and effective pathway to prepare MoS2-C materials with excellent electrochemical performance for the application in large-scale energy storage systems. 展开更多
关键词 Cellulose nanocrystals MoS2-C nanosheets Hierarchical microspheres Anode material Sodium-ion batteries
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基于内控视角下的军队院校资产处置工作思考 被引量:1
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作者 董文柱 李松林 邹晶 《社会科学前沿》 2019年第1期57-61,共5页
健全有效的内部控制体系是完善军队院校资产处置流程,提高资产管理效益的前提。通过分析军队院校资产处置的特点,从COSO内部控制框架的控制环境、风险评估、控制活动、信息系统与沟通、监督等内部控制五要素分析军队院校资产处置中存在... 健全有效的内部控制体系是完善军队院校资产处置流程,提高资产管理效益的前提。通过分析军队院校资产处置的特点,从COSO内部控制框架的控制环境、风险评估、控制活动、信息系统与沟通、监督等内部控制五要素分析军队院校资产处置中存在的问题,并提出相应的对策措施。 展开更多
关键词 内部控制 军队院校 资产处置
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基于计算机代数系统的常用航线在不同投影下的可视化
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作者 李松林 边少锋 +1 位作者 李厚朴 刘佳奇 《测绘科学技术》 2018年第3期196-202,共7页
等角航线、大圆航线与大椭圆航线作为航海与航空领域常用的航线,在不同地图投影下的表现不同,而通过航线方程难以直观地分析其三者在不同类型投影下的不同表现。计算机代数系统不仅具有强大的符号运算功能,而且具有很强的图像可视化功能... 等角航线、大圆航线与大椭圆航线作为航海与航空领域常用的航线,在不同地图投影下的表现不同,而通过航线方程难以直观地分析其三者在不同类型投影下的不同表现。计算机代数系统不仅具有强大的符号运算功能,而且具有很强的图像可视化功能,在地图投影展绘、投影变形的计算与分析、不同投影间的变换等方面的应用具有传统数学方法无法比拟的优势。因此借助常用的计算机代数系统Mathematica软件,分别基于地球球体模型与椭球体模型,在不同类型的地图投影下,展绘出等角航线、大圆航线和大椭圆航线,为航行人员提供精确直观的航线地图,为航空航海领域的航线规划相关研究和教学工作提供有力支撑。 展开更多
关键词 等角航线 大圆航线 大椭圆航线 计算机代数系统
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Effect of chicken haemoglobin powder on growth, feed utilization, immunity and haematological index of largemouth bass (Micropterus salmoides) 被引量:5
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作者 Guitao Ding songlin li +1 位作者 An Wanga Naisong Chen 《Aquaculture and Fisheries》 2020年第4期187-192,共6页
A 12-week feeding trial was conducted to evaluate the effects of replacing fish meal by chicken haemoglobin powder in largemouth bass diets.Four isonitrogenous(48%)and isolipidic(12%)diets were formulated to replace 0... A 12-week feeding trial was conducted to evaluate the effects of replacing fish meal by chicken haemoglobin powder in largemouth bass diets.Four isonitrogenous(48%)and isolipidic(12%)diets were formulated to replace 0%(control),9.80%,19.61%and 29.41%of fish meal with chicken haemoglobin powder.Each diet was fed to triplicate groups of fish(initial weight:49.50±0.07 g)twice daily.The fish specific growth rate was significantly reduced when diet replacement level was up to 19.61%,which may be related to the feed intake and apparent digestibility coefficient of protein and amino acids.Meanwhile,the feed efficiency ratio and protein efficiency ratio were not significantly decreased until the replacement level up to 29.41%.The activity of CCP was significantly reduced when 19.61%of fish meal was replaced.Meanwhile,the activity of lysozyme and serum protein content was significantly altered in fish fed with the diets up to 29.41%replacement.Additionally,the red blood cell count and haemoglobin content was significantly decreased when the replacement level was up to 19.61%.In overall,the diet with 9.80%of chicken haemoglobin powder was more suitable for largemouth bass. 展开更多
关键词 Chicken haemoglobin meal GROWTH Feed utilization Non-specific immunity Largemouth bass
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Crustal P-and S-Wave Velocity Structure of the North China Craton at 36°N from Active-Source Seismic Data and Its Tectonic Implications 被引量:1
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作者 Xiaofeng Tian Walter DMooney +3 位作者 Xiaoguo Deng songlin li Baofeng liu Hanqi liu 《Journal of Earth Science》 SCIE CAS CSCD 2022年第3期642-663,共22页
We present crustal models for seismic P-waves(Vp),S-waves(Vs)and the Vp/Vs ratio across the southern North China Craton along latitude 36°N.Our results are based on inverse and forward modeling of long-range wide... We present crustal models for seismic P-waves(Vp),S-waves(Vs)and the Vp/Vs ratio across the southern North China Craton along latitude 36°N.Our results are based on inverse and forward modeling of long-range wide-angle reflection/refraction data.The crust of the southern Ordos Block has high lower crustal velocity(7.0 km/s)and a Moho depth of~42 km.In contrast,thick sediments and a lower average velocity(compared with the Ordos block)found underneath the Shanxi Graben are likely to be the products of rifting that has occurred since the Cenozoic.Steep Moho dips,exposed basement rock and higher average crustal velocity beneath the Lüliang Mountain and the Taihang Mountain are characteristic of an orogenic belt.The Tanlu fault and the Liaocheng-Lankao fault show sharp crustal velocity variations and a Moho offset.This seismic profile sampled the entire region of the Eastern North China Craton where the cratonic root has been destroyed and the unique crustal structure is correlated with the substantially modified lithosphere.Our crustal seismic velocity model shows a strong correspondence between surface geology,local tectonics and the deep crustal structure. 展开更多
关键词 North China Craton crustal velocity structure craton destructure TECTONICS wideangle reflection/refraction
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Variation of lipids and fatty acids composition in the tissues of wild devil stinger(Inimicus japonicas)during sexual maturation
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作者 songlin li Wen Wen +2 位作者 Xu Gong Xuxiong Huang Naisong Chen 《Aquaculture and Fisheries》 2018年第3期115-121,共7页
The present study was conducted to characterize the lipid and fatty acid profiles in different tissues(gonad,liver and muscle)of the wild-caught devil stinger during sexual maturation.Wild-caught devil stinger were di... The present study was conducted to characterize the lipid and fatty acid profiles in different tissues(gonad,liver and muscle)of the wild-caught devil stinger during sexual maturation.Wild-caught devil stinger were divided into six groups according to gonad development and gender.Total lipid content was up to 40%dry weight in liver and was significantly higher than in other tissues(ovary,testis and muscle)in both male and female stinger during sexual maturation.During maturation,total lipid content in the female stinger liver decreased,but in males significantly increased in all tissues.Higher proportions of neutral lipids(NL)were observed in the stinger liver,while polar lipids(PL)were mainly quantified in the gonad and muscle of both male and female stinger.The PL content of the ovary significantly decreased with sexual maturation,but NL were significantly increased.The fatty acids composition of the stinger broodstocks were tissue-and lipid class-specific.In the stinger gonad high-unsaturated fatty acids(HUFA),such as ARA,DHA and EPA,are selectively transferred and conserved,indicating the crucial role of these fatty acids during sexual maturation of this fish species. 展开更多
关键词 LIPIDS Fatty acids composition Gonad development Devil stinger
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Statistically designed enzymatic hydrolysis of an icariin/b-cyclodextrin inclusion complex optimized for production of icaritin 被引量:3
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作者 Xin Jin Zhenhai Zhang +2 位作者 E.Suna songlin li Xiaobin Jia 《Acta Pharmaceutica Sinica B》 SCIE CAS 2012年第1期83-89,共7页
This study focuses on the preparation and enzymic hydrolysis of an icariin/bcyclodextrin inclusion complex to efficiently generate icaritin.The physical characteristics of the inclusion complex were evaluated by diffe... This study focuses on the preparation and enzymic hydrolysis of an icariin/bcyclodextrin inclusion complex to efficiently generate icaritin.The physical characteristics of the inclusion complex were evaluated by differential scanning calorimetry(DSC).Enzymatic hydrolysis was optimized for the conversion of icariin/b-cyclodextrin complex to icaritin by Box–Behnken statistical design.The inclusion complex formulation increased the solubility of icariin approximately 17-fold,from 29.2 to 513.5 mg/mL at 60℃.The optimum conditions were predicted by Box–Behnken statistical design as follows:60℃,pH 7.0,the ratio of enzyme/substrate(1:1.1)and reaction time 7 h.Under the optimal conditions the conversion of icariin was 97.91%and the reaction time was decreased by 68%compared with that without b-CD inclusion.Product analysis by melting point,ESI-MS,UV,IR,1H NMR and 13C NMR confirmed the authenticity of icaritin with a purity of 99.3%and a yield of 473 mg of icaritin from 1.1 g icariin. 展开更多
关键词 Icariin/b-CD inclusion complex SNAILASE Enzymatic hydrolysis Box–Behnken statistical design ICARITIN
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Study on Traditional Chinese Medicine theory of lung being connected with large intestine 被引量:4
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作者 Ping liu Ping Wang +3 位作者 Daizhi Tian Junfeng liu Gang Chen songlin li 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第3期482-487,共6页
OBJECTIVE:The theory of lung being connected with large intestine,which is a major topic in Traditional Chinese Medicine(TCM),has guided clinical practice for thousands of years in China.METHODS:In this study,we analy... OBJECTIVE:The theory of lung being connected with large intestine,which is a major topic in Traditional Chinese Medicine(TCM),has guided clinical practice for thousands of years in China.METHODS:In this study,we analyzed the history,main contents,clinical application,and material basis of the theory,to attempt to improve the potential clinical significance of "lung being connected with large intestine" in China.RESULTS:The lung being connected with large intestine was first described in "Huang Di Nei Jing",and formed one of the basic theories of TCM.For thousands of years,the majority of TCM practitioners explored this theory continuously,leading to its development and use as an important theory in the guidance of TCM clinics In the last decade,researchers in the field of integrated TCM and Western medicine have studied clinical applications and biomedical mechanisms with experimental methods to explore the implications of the theory.CONCLUSION:With the further development of science and technology,research concerning the theory of lung being connected with large intestine will be greatly stimulated and contribute to the modernization of TCM. 展开更多
关键词 Lung being connected with large intestine Traditional Chinese Medicine Clinical application
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Effect of MWCNTs Additive on Desorption Properties of Zn(BH_4)_2 Composite Prepared by Mechanical Alloying
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作者 Baogang Yang songlin li +2 位作者 Hang Wang Jintao Xiang Qiumin Yang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2013年第8期715-719,共5页
In this study, the effect of multi-walled carbon nanotubes (MWCNTs) additive on the dehydriding properties of the Zn(BH4)2/NaCl composite prepared by high energy ball milling were investigated. X-ray diffraction ... In this study, the effect of multi-walled carbon nanotubes (MWCNTs) additive on the dehydriding properties of the Zn(BH4)2/NaCl composite prepared by high energy ball milling were investigated. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) results demonstrated that Zn(BH4)2 was produced from mechanochemical reaction between ZnCl2 and NaBH4. Compared with the undoped sample, 10 wt% MWCNTs effectively lowered the decomposition temperature of Zn(BH4)2 by 15 ℃. The complex released 3.6 wt% hydrogen within 250 s at 100 ℃ and totally released 4.5 wt% hydrogen within 2500 s, indicating it has a considerable potential as a hydrogen storage material. 展开更多
关键词 Hydrogen storage material Metal borohydride Mechanical alloying Multi-wailed carbon nanotubes (MWCNTs)
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