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Stabilization of low-valence transition metal towards advanced catalytic effects on the hydrogen storage performance of magnesium hydride

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Journal of Magnesium and Alloys 2021年第2期9卷 647-657页

作者： Jian Zhang Shuai Yan Guanglin Xia Xiaojie Zhou Xianzheng Lu linping yu Xuebin yu Ping Peng Hunan Provincial Key Laboratory of Intelligent Manufacturing Technology for High-performance Mechanical Equipment Changsha University of Science and TechnologyChangsha 410114China Department of Materials Science Fudan UniversityShanghai 200433China School of Chemistry and Biological Engineering Changsha University of Science and TechnologyChangsha 410114China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Magnesium hydride(MgH_(2))has been widely regarded as a potential hydrogen storage material owing to its high gravimetric and volumetric capacity.Its sluggish kinetics and high activation energy barrier,however,severely limit its practical application.Transition metal oxides(TMOs)have been extensively used as catalysts to improve the hydrogen storage performance of MgH_(2),but the low-valence transition metal(TM)ions,resulting from the reduction of TMOs accompanied by the formation of inactive Mg O,have been demonstrated to be the most effective components.Herein,we theoretically and experimentally confirm that the doping of low-valence TMs into Mg O could effectively weaken the Mg-H bonds and decrease the energy required for hydrogen desorption from MgH_(2),leading to superior catalytic activity compared to both TMOs and Mg O.In particular,the apparent activation energy for the dehydrogenation of Mg(Nb)O-catalyzed MgH_(2)could be reduced to only 84.1 kJ mol^(-1),and the reversible capacity could reach around 7 wt.%after 5 cycles with a capacity retention of 96%.Detailed theoretical calculations confirm that the remarkable orbital hybridization between Mg(Nb)O and MgH_(2)promotes charge transfer from MgO to the MgH_(2)monomer,resulting in significantly weakened stability of MgH_(2),which could effectively enhance its hydrogen storage performance.

关键词： Magnesium hydride Hydrogen storage Dehydrogenation Catalysts First-principles calculations Solid-solution

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Corrigendum to“Cation-vacancy induced Li+intercalation pseudocapacitance at atomically thin heterointerface for high capacity and high power lithium-ion batteries”[J.Energy Chem.62(2021)281–288]

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Journal of Energy Chemistry 2022年第8期31卷 655-656页

作者： Ding yuan David Adekoya yuhai Dou yuhui Tian Hao Chen Zhenzhen Wu Jiadong Qin linping yu Jian Zhang Xianhu Liu Shi Xue Dou Shanqing Zhang Centre for Clean Environment and Energy School of Environment and ScienceGold Coast CampusGriffith UniversityGold Coast 4222Australia Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation Changsha University of Science and TechnologyChangsha 410114HunanChina National Engineering Research Centre for Advanced Polymer Processing Technology Zhengzhou UniversityZhengzhou 450002HenanChina Institute for Superconducting and Electronic Materials University of Wollongong AustraliaWollongong 2500Australia

The authors regret that the wrong image of Fig.1 was uploaded in the paper.The correct one should be:We confirm the discrepancy is restricted to the image of Fig.1 only,the underlying data is correct and unchanged.The... 详细信息

关键词： lithium capacitance unchanged

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Cation-vacancy induced Li+ intercalation pseudocapacitance at atomically thin heterointerface for high capacity and high power lithium-ion batteries

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Journal of Energy Chemistry 2021年第11期30卷 281-288,I0006页

It is challenging to create cation vacancies in electrode materials for enhancing the performance of rechargeable lithium ion batteries (LIBs). Herein, we utilized a strong alkaline etching method to successfully create Co vacancies at the interface of atomically thin Co_(3−x)O_(4)/graphene@CNT heterostructure for high-energy/power lithium storage. The creation of Co-vacancies in the sample was confirmed by high-resolution scanning transmission electron microscope (HRSTEM), X-ray photoelectron spectroscopy (XPS) and electron energy loss near-edge structures (ELNES). The obtained Co_(3−x)O_(4)/graphene@CNT delivers an ultra-high capacity of 1688.2 mAh g^(−1) at 0.2 C, excellent rate capability of 83.7% capacity retention at 1 C, and an ultralong life up to 1500 cycles with a reversible capacity of 1066.3 mAh g^(−1). Reaction kinetic study suggests a significant contribution from pseudocapacitive storage induced by the Co-vacancies at the Co_(3−x)O_(4)/graphene@CNT interface. Density functional theory confirms that the Co-vacancies could dramatically enhance the Li adsorption and provide an additional pathway with a lower energy barrier for Li diffusion, which results in an intercalation pseudocapacitive behavior and high-capacity/rate energy storage.

关键词： Cation vacancy Atomically thin Interface Pseudocapacitance Lithium-ion batteries

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中国高食味北方粳稻与南方半糯粳稻品种理化特性及食味品质的差异分析

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中国农业科学 2024年第3期57卷 469-483页

作者：朱大伟郑欣余静牟仁祥陈铭学邵雅芳章林平中国水稻研究所/农业农村部稻米及制品质量监督检验测试中心

【目的】明确我国优质北方粳稻和南方半糯性粳稻稻米理化特性与米饭感官食味品质的差异，为优质粳稻培育提供依据。【方法】以代表性高食味北方粳稻品种、南方半糯性粳稻品种为材料，以日本越光大米为对照，系统分析比较2种类型粳米外... 详细信息

【目的】明确我国优质北方粳稻和南方半糯性粳稻稻米理化特性与米饭感官食味品质的差异，为优质粳稻培育提供依据。【方法】以代表性高食味北方粳稻品种、南方半糯性粳稻品种为材料，以日本越光大米为对照，系统分析比较2种类型粳米外观品质、淀粉精细结构、蛋白组分、米粉糊化特性、米饭质地和感官食味品质的差异。【结果】虽然3个北方粳稻品种和3个南方半糯性粳稻品种具有较高的感官食味值，但在淀粉精细结构、蛋白组分、米粉糊化特性和米饭质地等指标上存在显著性差异。在米饭感官食味方面，3个高食味北方粳稻品种表现出较好的适口性（96—98分），3个南方半糯性粳稻品种表现出较好的冷饭质地（92—100分）。在理化特性方面，3个北方粳稻品种表现出较高的表观直链淀粉含量（17.6%—19.6%），较低的粗蛋白含量、醇溶蛋白和谷蛋白含量。3个南方半糯性粳稻品种表现出较低的直链淀粉含量（8.5%—10.5%），较高的谷蛋白及醇溶蛋白含量。在淀粉精细结构方面，3个南方半糯性粳稻品种的直链淀粉含量和直支比较低（均值低54.7%和55.6%），支链淀粉链长分布相似度高。此外，南粳46和宁香粳9号的直链淀粉短链与长链比高于五优稻4号和天隆优619（均值高43.2%）。因此，与北方粳稻相比，南方半糯性粳稻品种的米粉具有较高的糊化温度、峰值黏度、崩解值，较低的消减值，米饭具有较高的黏度、较小的硬度和弹性。【结论】高食味北方粳稻品种具有较低的糊化温度，适中的硬度和较好的弹性；而高食味南方半糯性粳稻品种表现出较高的崩解值，其米饭黏度较高，外观较好。

关键词：粳稻食味感官评价淀粉结构糊化特性

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电压源型风电比例影响区域电网频率调整研究

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电网与清洁能源 2024年第3期40卷 99-106页

作者：谢醉冰李欣陶佳鑫马龙涛王吉利曾林平张宇李雷国家电网有限公司西北分部陕西西安710048 西安理工大学电气工程学院陕西西安710054

随着新能源大比例接入新型电力系统中,区域电网的频率稳定性问题凸显。为了研究风电在区域电网中对新能源系统稳定运行能力的影响,针对电压源型风电占比对区域电网频率调整的影响开展研究。对风电频率需求相应特性和电压源型风电机组控... 详细信息

随着新能源大比例接入新型电力系统中,区域电网的频率稳定性问题凸显。为了研究风电在区域电网中对新能源系统稳定运行能力的影响,针对电压源型风电占比对区域电网频率调整的影响开展研究。对风电频率需求相应特性和电压源型风电机组控制进行分析,提出了在电压源型风电机组不同占比结构下的区域电网新能源场站容量分配评估方法。在Matlab/Simulink中对不同电压源型风电占比下的电网频率响应特性进行验证。结果表明,随着在混合风电场内配置一定比例的电压源型风电机组,可以有效地改善区域电网的频率稳定性。

关键词：高比例新能源风力发电电压源型风机一次调频

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于志强治疗肝硬化腹水药对经验浅析

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湖北中医杂志 2024年第3期46卷 29-32页

作者：袁娜朱林平天津中医药大学天津300193 天津中医药大学第二附属医院天津300250

腹水是肝硬化最常见并发症,属中医“臌胀”“单腹胀”“水肿”的范畴,主要特征有“腹部胀大如鼓、绷急苍黄、脉络显露”等,病机复杂,迁延难愈,常被认为是中医内科“风、痨、臌、膈”4大难病之一^([1])。现代研究表明肝功能减退及门静脉... 详细信息

腹水是肝硬化最常见并发症,属中医“臌胀”“单腹胀”“水肿”的范畴,主要特征有“腹部胀大如鼓、绷急苍黄、脉络显露”等,病机复杂,迁延难愈,常被认为是中医内科“风、痨、臌、膈”4大难病之一^([1])。现代研究表明肝功能减退及门静脉高压均可导致肝硬化腹水,晚期易影响多个系统功能失调。调查显示^([2]),肝硬化腹水患者近年来病死率居高不下,已经严重危害患者生命健康。

关键词：肝硬化腹水药对临床经验于志强

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DynamicMechanical and Chemorheology Analysis for the Blended Epoxy System with Polyurethane Modified Resin

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Journal of Renewable Materials 2022年第4期10卷 1081-1095页

作者： Xue Xin yu Rong linping Su Zhengmei Qiu Chenjun Yang Ming Liang Ping Ji Guoqiang Zhong Zhanyong Yao School of Qilu Transportation Shandong UniversityJinan250002China Shandong Hi-Speed Group Co. Ltd.Jinan250014China Shandong Provincial Communications Planning and Design Institute Group Co. Ltd.Jinan250031China

As the important matrix material,epoxy resin has been widely used in the composites for various fields.On account of the poor toughness of epoxy resin limiting their suitability for advanced applications,considerable interests have been conducted to modify the epoxy resin to meet the engineering requirements.In this study,the bio-based polyurethane(PU)modified resin was adopted to modify the pure bisphenol-A epoxy by blending method with various proportions.Aiming to illuminate the curing behavior,mechanical and thermal properties,the blended epoxy systems were characterized by viscosity-time analysis,dynamic mechanical analysis(DMA)at different frequencies and temperatures,mechanical tensile test,thermogravimetric analysis(TGA)and Fourier transform infrared(FT-IR)spectroscopy.The results indicated that the introduction of PU modified epoxy was found to significantly inhibit the viscosity growth rates especially when the content of PU modified epoxy resin is higher than 60%.Notwithstanding the dynamic modulus and T_(g)reduced with the increment of PU modified epoxy,remarkable increment on the elongation at break was found and the flexibility was greatly promoted with the introduction of PU modified epoxy.The proportion of PU modified epoxy in the blends should be put balance considerations to obtain optimal mechanical properties.TGA results and FTIR spectrum demonstrated that the addition of PU modified epoxy did not change the thermal decomposition mechanism and chemical reaction mechanism,but the addition of PU modified epoxy inhibits the curing reaction of epoxy resin by measured and calculated the damping temperature domainT from 35.7℃ to 48.9℃.

关键词： Dynamic mechanical property chemorheology analysis blended epoxy system polyurethane modified resin

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N掺杂和光化学合成CoSex助催化剂改性石墨相氮化碳以提高其光催化产氢性能

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Journal of Donghua University(English Edition) 2024年第3期41卷 249-256页

作者：刘思伟郗传俊张琳萍宣为民侯煜东华大学化学与化工学院上海201620 东华大学生态纺织教育部重点实验室上海201620

开发一种高效的产氢光催化剂对于将太阳能转化为氢能至关重要。该研究将氮掺杂石墨相氮化碳(CN)与光化学合成得到的助催化剂CoSex相结合,通过原位合成制备了一种高效的光催化产氢材料。该材料的最佳光催化性能较CN提高285倍。光电化学... 详细信息

开发一种高效的产氢光催化剂对于将太阳能转化为氢能至关重要。该研究将氮掺杂石墨相氮化碳(CN)与光化学合成得到的助催化剂CoSex相结合,通过原位合成制备了一种高效的光催化产氢材料。该材料的最佳光催化性能较CN提高285倍。光电化学试验表明,氮掺杂和引入CoSex可以有效促进光生电荷载流子的分离,从而提高CN的产氢活性。该工作为利用光化学沉积方法制备新型光催化剂提供了新的视角。

关键词：光催化剂 CoSex 助催化剂产氢氮掺杂

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Geochemical study and significance of sequential extraction in reservoir rocks of Turpan-Hamin Basin

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Chinese Science Bulletin 2004年第S1期49卷 32-38页

作者： yu linping PAN Changchun FU Jiamo State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Seven samples collected from the Turpan-Hamin Basin were treated by sequential extraction method. Analytical results indicate that the free oils, inclusion oils (oil-bearing fluid inclusions) and clay-adsorbed oils vary significantly. The geochemical characteristics of inclusion and clay-adsorbed oils correlate well with the lacustrine mudstones. The characteristics are as follows: (i) with higher Ph/nC18 ratio and lower Pr/Ph ratio; (ii) with higher values of C26 tricyclic/C24 tetracyclic terpane, C23 tricyclic ter-pane/(C23 tricyclic terpane+C3017α(H) hopane), C21/(C21+C29) sterane, Ts/Tm and C29Ts/C29l7α(H) norhopane and lower value of C19/C21 tricyclic terpane; (iii) with relatively high content of C27 and C28 sterane and lower abundance of C29 sterane and diasterane. They indicate that the early charged oils are derived from the pre-Jurassic lacustrine mudstones and the later charged oils are from the Jurassic coal-bearing strata or coals.

关键词： Turpan-Hamin Basin sequential extraction free oils oil-bearing fluid inclusions clay-adsorbed oils.

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Stereotactic body radiation therapy versus radiofrequency ablation in patients with small hepatocellular carcinoma:a systematic review and meta-analysis

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Hepatobiliary Surgery and Nutrition 2021年第5期10卷 623-630,I0008页

作者： Jiawei Hong linping Cao Haiyang Xie yuanxing Liu Jun yu Shusen Zheng Division of Hepatobiliary and Pancreatic Surgery Department of SurgeryFirst Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouChina Key Lab of Combined Multi-Organ Transplantation Ministry of Public HealthHangzhouChina The Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Zhejiang UniversityHangzhouChina

Background:This study aimed to compare the clinical outcomes and toxicity between small hepatocellular carcinoma(HCC)patients treated with stereotactic body radiation therapy(SBRT)and those treated with radiofrequency ablation(RFA).Methods:We searched databases for relevant clinical studies.The primary outcomes of interest were overall survival(OS)at 1 and 2 years,freedom from local progression(FFLP)rate at 2 years,and complications.Results:Five cohorts from 5 retrospective studies and 4,814 patients with HCC were included.Pooled OS at 2 years was significantly lower for SBRT than for RFA[odds ratio(OR):0.63;95%confidence interval(CI):0.51-0.79;P<0.0001],but the pooled FFLP rate at 2 years was higher for SBRT than for RFA(OR:1.66;95%CI:1.05-2.61;P=0.03).In addition,there was no significant difference in the local and liver toxicities of the two treatments.The contradictory conclusion between the OS and FFLP outcome may be attributed to the difference in radiological dose and location,but there were no uniform criteria to illustrate the radiological dose and location in the included studies.Conclusions:SBRT had a higher local control ratio but poorer prognosis than RFA in patients with small HCC.The local toxicity was comparable in both treatments.Further trials should be designed with uniform standards for SBRT and RFA treatments.

关键词： Hepatocellular carcinoma(HCC) stereotactic body radiation therapy(SBRT) radiofrequency ablation(RFA) meta-analysis

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