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Highly efficient and stable electrocatalyst for hydrogen evolution by molybdenum doped Ni-Co phosphide nanoneedles at high current density

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Nano Research 2024年第3期17卷 1066-1074页

作者： Chengyu huang Zhonghong Xia Jing Wang Jing Zhang Chenfei Zhao Xingli Zou shichun Mu Jiujun Zhang Xionggang Lu Hong Jin Fan Shengjuan Huo Yufeng Zhao College of Sciences&Institute for Sustainable Energy Shanghai UniversityShanghai 200444China State Key Laboratory of Metastable Materials Science and Technology Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource ReuseYanshan UniversityQinhuangdao 066004China State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and EngineeringShanghai UniversityShanghai 200444China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore639798

There is an increasingly urgent need to develop cost-effective electrocatalysts with high catalytic activity and stability as alternatives to the traditional Pt/C in catalysts in water electrolysis.In this study,microspheres composed of Mo-doped NiCoP nanoneedles supported on nickel foam were prepared to address this challenge.The results show that the nanoneedles provide sufficient active sites for efficient electron transfer;the small-sized effect and the micro-scale roughness enhance the entry of reactants and the release of hydrogen bubbles;the Mo doping effectively improves the electrocatalytic performance of NiCoP in alkaline media.The catalyst exhibits low hydrogen evolution overpotentials of 38.5 and 217.5 mV at a current density of 10 mA·cm^(-2) and high current density of 500 mA·cm^(-2),respectively,and only 1.978 V is required to achieve a current density of 1000 mA·cm^(-2) for overall water splitting.Density functional theory(DFT)calculations show that the improved hydrogen evolution performance can be explained as a result of the Mo doping,which serves to reduce the interaction between NiCoP and intermediates,optimize the Gibbs free energy of hydrogen adsorption(△G_(*H)),and accelerate the desorption rate of *OH.This study provides a promising solution to the ongoing challenge of designing efficient electrocatalysts for high-current-density hydrogen production.

关键词： transition metal phosphides Mo-doped NiCoP hydrogen evolution reaction gradient hydrothermal water splitting

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圆形流管内高阶混合模态激发的全局标定方法

实验流体力学 2024年第1期38卷 37-45页

作者：高康郐浩瑜黄时春余亮蒋伟康上海交通大学机械系统与振动全国重点实验室上海200240 西北工业大学民航学院西安710072 大型客机集成技术与模拟飞行全国重点实验室上海200126

声模态发生器是通过调控扬声器阵列,进而在管道内激发特定阶次声模态的一种装置,可用于流管内气动噪声传播和环形声衬的降噪研究。使用多圈布置的扬声器阵列模态发生器,通过调节各个声源的幅值和相位,可实现高阶周向、径向和混合模态的... 详细信息

声模态发生器是通过调控扬声器阵列,进而在管道内激发特定阶次声模态的一种装置,可用于流管内气动噪声传播和环形声衬的降噪研究。使用多圈布置的扬声器阵列模态发生器,通过调节各个声源的幅值和相位,可实现高阶周向、径向和混合模态的激发。然而,扬声器阵列系统的通道输出偏差会在目标模态激发时产生显著的干扰模态。为消除扬声器系统通道输出差异对模态激发的影响,提出了基于最小二乘全局标定的流管内高阶混合模态激发方法。通过对扬声器声源的通道输出偏差进行全局建模,引入激励补偿因子和流场校正因子,将有流情况下各扬声器的系统输出偏差求解问题转换为无流情况下单个扬声器工作时的模态识别问题,通过矩阵变换和最小二乘法求解各扬声器的激励补偿因子,最终实现扬声器的幅值和相位激励修正。将所发展的模态激发与全局标定方法应用于所研制的圆形流管模态激发装置,结果表明:干扰模态的强度被显著抑制,且在工作频率范围内,目标激发模态的相对目标模态系数不低于10 dB。

关键词：圆形流管模态发生器管道模态声源输出偏差全局标定

A Comparative Study on the Buoyancy of Resting Eggs from Different Artemia Populations, with Emphasis on Its Relationships with Habitat Salinity and Biometric Characters of Resting Eggs

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Journal of Ocean University of China 2022年第6期21卷 1585-1596页

作者： ZHOU Jiaxuan huang Zhike GUO Yan SUN shichun The Key Laboratory of Mariculture(Ministry of Education) and Institute of Evolution&Marine BiodiversityOcean University of ChinaQingdao 266003China Xinjiang Uygur Autonomous Region Fisheries Research Institute Urumqi 830002China

The buoyancy of Artemia resting eggs is a feature with both biological and economic importance.Since the buoyancy of resting eggs is dependent on the specific weight of the eggs or salinity of ambient water,we suppose that habitat salinity may exert a selection pressure on resting egg buoyancy,and thereby lower habitat salinity may result in better floating capacity of resting eggs and vice versa.In this study,we compared the floating capacity of resting eggs from 25 Artemia populations.The results showed that the floating capacity of resting eggs varied greatly among different populations.The minimum salinity to float some eggs varied from 0 to 180.The salinity at which all resting eggs floated varied from 80 to 320.The FS_(50)(salinity with 50%eggs floating)of Zhundong and Yuncheng population was not detectable(over 50%eggs floating in distilled water),that of Kyêbxang Co population was 4.3,while the maximum value found in Dabancheng population was 234.5.In terms of the‘apparent specific weight’of resting eggs,18 populations exhibited a single-peak distribution pattern,while the other 7 populations showed a multiple-peak or non-peak distribution.Negative correlations were found between FS50 and chorion thickness,and between FS_(50) and the volume percentage of the chorion in eggs,supporting a previous standpoint that shell thickness was a determinative factor for the floating capacity of resting eggs.A positive correlation was determined between FS50 and habitat salinity.The hypothesis that habitat salinity may cause a directional selection on the buoyancy of resting eggs seems to be true.

关键词： brine shrimp cyst floating capacity shell thickness

Coupled deep-mantle carbon-water cycle: Evidence from lower-mantle diamonds

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The Innovation 2021年第2期2卷 47-53页

作者： Wenzhong Wang Oliver Tschauner shichun huang Zhongqing Wu Yufei Meng Hans Bechtel Ho-Kwang Mao Laboratory of Seismology and Physics of Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Department of Geoscience University of Nevada Las VegasLas VegasNV 89154USA CAS Center for Excellence in Comparative Planetology USTCHefeiHefei 230026China Center for High Pressure Science and Technology Advanced Research Shanghai 201203China Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Earth Sciences University College LondonLondon WC1E 6BTUK Earth and Planets Laboratory Carnegie Institution for ScienceWashingtonDC 20015USA

Diamonds form in a variety of environments between subducted crust,lithospheric and deep mantle.Recently,deep source diamonds with inclusions of the high-pressure H2O-phase ice-VII were discovered.By correlating the pressures of ice-VII inclusions with those of other high-pressure inclusions,we assess quantitatively the pressures and temperatures of their entrapment.We show that the iceVII-bearing diamonds formed at depths down to 800±60 km but at temperatures 200–500 K below average mantle temperature that match the pressure-temperature conditions of decomposing dense hydrous mantle silicates.Our work presents strong evidence for coupled recycling of water and carbon in the deep mantle based on natural samples.

关键词： diamond deep mantle water and carbon cycle first-principles calculations

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电动汽车热失控危害性评测技术研究

消防科学与技术 2024年第5期43卷 756-761页

作者：张良赵志伟张得胜黄盟周思达杨世春刘国芳北京航空航天大学交通科学与工程学院北京100191 应急管理部天津消防研究所天津300381 工业与公共建筑火灾防控技术应急管理部重点实验室天津300381 天津市消防安全技术重点实验室天津300381 中国汽车工程研究院股份有限公司重庆401122 中国汽车工程学会北京102600

随着电动汽车保有量的增加,动力电池热失控导致的着火事故时有发生,对热失控危险性进行评测是提升电动汽车安全性能的重要手段之一,而行业内尚未形成量化评估方法。针对上述问题,搭建了电动汽车整车燃烧试验平台,并开展了大量由热失控... 详细信息

随着电动汽车保有量的增加,动力电池热失控导致的着火事故时有发生,对热失控危险性进行评测是提升电动汽车安全性能的重要手段之一,而行业内尚未形成量化评估方法。针对上述问题,搭建了电动汽车整车燃烧试验平台,并开展了大量由热失控引发电动汽车火灾的模拟试验,提取了以下可用于电动汽车热失控危害性评测的参考指标与部分潜在指标:试验开始至动力电池热失控的时间间隔可作为电池故障预警有效性的指标;热失控至车辆起火的时间间隔与车内温度可作为乘员逃生安全性的指标;烟气体积分数超标时刻及其与起火时刻的关系可作为驾驶室毒气危害性的指标;车内可燃气体体积分数和车外热辐射强度可作为评估爆炸危险性和相邻车辆引燃风险性的指标。通过提出上述评价指标,为后续形成量化评估方法及相关标准提供参考。

关键词：电动汽车热失控危害性评测方案

轴承温度检测与智能润滑系统在小麦加工中的应用

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粮食加工 2024年第1期49卷 47-49页

作者：黄金源赖世椿刘子立詹育生刘锐广州市岭南穗粮谷物股份有限公司广州511466

经过对小麦制粉工艺长期生产探索与实践,在分析传统人工设备检查维修效率低下原因的基础上,提出了一种基于PLC控制的轴承温度检测与自动润滑系统,采用该系统可保障设备长期稳定运行,提高制粉企业经济效益。

关键词：小麦加工轴承温度检测智能润滑系统

Mantle geochemistry: Insights from ocean island basalts

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Science China Earth Sciences 2017年第11期60卷 1976-2000页

作者： huang shichun ZHENG YongFei Department of Geoscience University of Nevada CAS Key Laboratory of Crust-Mantle Material and Environment School of Earth and Space Sciences University of Science and Technology of China

The geochemical study of the Earth's mantle provides important constraints on our understanding of the formation and evolution of Earth, its internal structure, and the mantle dynamics. The bulk Earth composition is inferred by comparing terrestrial mantle rocks with chondrites, which leads to the chondritic Earth model. That is, Earth has the same relative proportions of refractory elements as that in chondrites, but it is depleted in volatiles. Ocean island basalts(OIB) may be produced by mantle plumes with possible deep origins; consequently, they provide unique opportunity to study the deep Earth. Isotopic variations within OIB can be described using a limited number of mantle endmembers, such as EM1, EM2 and HIMU, and they have been used to decipher important mantle processes. Introduction of crustal material into the deep mantle via subduction and delamination is important in generating mantle heterogeneity; however, there is active debate on how they were sampled by mantle melting, i.e.,the role of olivine-poor lithologies in the OIB petrogenesis. The origin and location of high 3He/4He mantle remain controversial,ranging from unprocessed(or less processed) primitive material in the lower mantle to highly processed materials with shallow origins, including ancient melting residues, mafic cumulates under arcs, and recycled hydrous minerals. Possible core-mantle interaction was hypothesized to introduce distinctive geochemical signatures such as radiogenic 186 Os and Fe and Ni enrichment in the OIB. Small but important variations in some short-lived nuclides, including 142 Nd, 182 W and several Xe isotopes, have been reported in ancient and modern terrestrial rocks, implying that the Earth's mantle must have been differentiated within the first 100 Myr of its formation, and the mantle is not efficiently homogenized by mantle convection.

关键词：地球化学特征地幔动力学洋岛玄武岩球粒陨石地幔不均一性地幔熔融原始材料氙同位素

Ultra-small platinum nanoparticles segregated by nickle sites for efficient ORR and HER processes

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Journal of Energy Chemistry 2022年第2期31卷 48-54页

作者： Lvhan Liang Huihui jin huang Zhou Bingshuai Liu Chenxi Hu Ding Chen Jiawei Zhu Zhe Wang Hai-Wen Li Suli Liu Daping He shichun Mu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong LaboratoryXianhu Hydrogen ValleyFoshan 528200GuangdongChina Hubei Engineering Research Center of RF-Microwave Technology and Application Wuhan University of TechnologyWuhan 430070HubeiChina Platform of Inter/Transdisciplinary Energy Research International Research Center for Hydrogen EnergyInternational Institute for Carbon-Neutral Energy ResearchYushu UniversityFukuoka 819-0395Japan Key Laboratory of Advanced Functional Materials of Nanjing Nanjing Xiaozhuang UniversityNanjing 211171JiangsuChina

In the electrochemical process,Pt nanoparticles(NPs)in Pt-based catalysts usually agglomerate due to Oswald ripening or lack of restraint,ultimately resulting in reduction of the active sites and catalytic efficiency.How to uniformly disperse and firmly fix Pt NPs on carbon matrix with suitable particle size for catalysis is still a big challenge.Herein,to prevent the agglomeration and shedding of Pt NPs,Ni species is introduced and are evenly dispersed in the surface of carbon matrix in the form of Ni-N-C active sites(Ni ZIF-NC).The Ni sites can be used to anchor Pt NPs,and then effectively limit the further growth and agglomeration of Pt NPs during the reaction process.Compared with commercial Pt/C catalyst,Pt@Ni ZIF-NC,with ultralow Pt loading(7 wt%)and ideal particle size(2.3 nm),not only increases the active center,but also promotes the catalysis kinetics,greatly improving the ORR and HER catalytic activity.Under acidic conditions,its half-wave potential(0.902 V)is superior to commercial Pt/C(0.861 V),and the mass activity(0.38 A per mg Pt)at 0.9 V is 4.7 times that of Pt/C(0.08 A per mg Pt).Besides,it also shows outstanding HER performance.At 20 and 30 mV,its mass activity is even 2 and 6 times that of Pt/C,respectively.Whether it is under ORR or HER conditions,it still shows excellent durability.These undoubtedly indicate the realization of dual-functional catalysts with low-Pt and high-efficiency properties.

关键词： Oxygen reduction reaction Hydrogen evolution reaction Zeolitic imidazolate frameworks Nickle site Pt nanoparticles

A preliminary investigation on the occurrence and distribution of antibiotic resistance genes in the Beijiang River, South China

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Journal of Environmental Sciences 2013年第8期25卷 1656-1661页

作者： Zhenhao Ling Ying Yang Yuanli huang shichun Zou Tiangang Luan School of Marine Sciences Sun Yat-sen University Department of Civil and Environmental Engineering Hong Kong Polytechnic University Environmental Biotechnology Lab Department of Civil Engineering The University of Hong Kong Guangzhou Quality Supervision and Testing Institute

The occurrence of antibiotic resistance genes （ARGs） was investigated and quantified in 20 water samples collected in the Beijiang River, South China. Sulfonamide- and tetracycline-resistant bacteria were present in 17 and 14 of the collected 20 samples. For sulfonamide ARGs, sulI and sulII were frequently observed in the Beijiang River. The levels of sulI were higher than sulII （p 〈 0.05）, with the mean values of （1.41 ± 1.12） × 10-2 and （1.58 ± 1.71） × 10-3 copies/16S rDNA, respectively. For tetracycline ARGs, tetG had the highest frequency, 100%, followed by tetA （85%）, tetO （85%）, tetC （70%）, tetX （60%）, tetM （40%） and tetQ （20%）, while tetE and tetS were not detected in all the samples from the Beijiang River. On the other hand, tetC had the highest concentration, ranging from 8.30 × 10-2 to 13.20 copies/16S rDNA. The poor correlation between ARGs and antibiotic concentrations revealed that the self-amplification and persistence of ARGs were the reasons that made ARGs exist in the water environment even though the antibiotic selecting pressure was absent. Because so few field measurements have been conducted for investigating the levels of ARGs in rivers in South China, this study provides an important insight on better understanding the occurrence and spread of ARGs in such an ecosystem.

关键词： antibiotic resistant genes Beijiang River South China