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Attribute-Based Authentication Scheme from Partial Encryption for Lattice with Short Key
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作者 wangke Yu shuhua wang 《Computers, Materials & Continua》 SCIE EI 2023年第4期67-80,共14页
Wireless network is the basis of the Internet of things and theintelligent vehicle Internet. Due to the complexity of the Internet of things andintelligent vehicle Internet environment, the nodes of the Internet of th... Wireless network is the basis of the Internet of things and theintelligent vehicle Internet. Due to the complexity of the Internet of things andintelligent vehicle Internet environment, the nodes of the Internet of thingsand the intelligent vehicle Internet are more vulnerable to malicious destructionand attacks. Most of the proposed authentication and key agreementprotocols for wireless networks are based on traditional cryptosystems such aslarge integer decomposition and elliptic curves. With the rapid developmentof quantum computing, these authentication protocols based on traditionalcryptography will be more and more threatened, so it is necessary to designsome authentication and key agreement protocols that can resist quantumattacks. In this paper, an anti-quantum authentication scheme for wirelessnetworks based on lattice cryptosystem is constructed. In the attribute-basedauthentication scheme, the length of the authenticated public-private keypair depends on the maximum order and complexity of the formula in thealgorithm. In the attribute-based authentication scheme, there is a certaincorrelation between the authenticated data and the attribute value of theuser in the scheme. We show that the attribute-based authentication schemegives an attribute-based with smaller public-private key pairs. The securityof the attribute-based authentication scheme is based on the sub-exponentialhard problem of the LWE (Learning With Errors). The Q-poly made bythe adversary in the scheme, and our attribute-based authentication schemeguarantees that private data about user attributes and ciphertext cannot beobtained by malicious attackers. 展开更多
关键词 AUTHENTICATION learning with errors partial encryption SECURITY
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大学英语教学课程思政路径设计
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作者 王淑花 张玲 《教育研究前沿(中英文版)》 2022年第2期140-143,共4页
大学英语课程思政是课程思政大背景和新文科建设提出的迫切要求。但是目前大学英语课程思政的教学方法上存在一系列的现实问题。错误的理解大学英语课程思政,把握不好思政教育的尺度,很容易在学生中滋生反感兴趣,不但不利于思政教育的实... 大学英语课程思政是课程思政大背景和新文科建设提出的迫切要求。但是目前大学英语课程思政的教学方法上存在一系列的现实问题。错误的理解大学英语课程思政,把握不好思政教育的尺度,很容易在学生中滋生反感兴趣,不但不利于思政教育的实施,甚至会影响正常的大学英语教学。本文以隐性教育和显性教育理论为出发点,为大学英语课程思政“三为+三不为”的方针指导下,设计了两度两性的大学英语课程思政的实施路径,促进大学英语课程更好地融入思政教育,帮助学生树立更强的文化自信和国家认同感。 展开更多
关键词 大学英语 课程思政 路径
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Weaker Interactions in Zn^(2+)and Organic Ion-pre-intercalated Vanadium Oxide toward Highly Reversible Zinc-ion Batteries 被引量:3
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作者 Feng Zhang Xiucai Sun +7 位作者 Min Du Xiaofei Zhang Wentao Dong Yuanhua Sang Jianjun wang Yanlu Li Hong Liu shuhua wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2021年第4期620-630,共11页
Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinet... Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinetics of divalent charge Zn^(2+)in the cathode materials caused by the strong electrostatic interaction and their unsatisfactory cycle life hinder the development of ZIBs.Herein,organic cations and Zn^(2+)ions co-pre-inserted vanadium oxide([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O are reported as the cathode for ultra-stable aqueous ZIBs,in which the weaker electrostatic interactions between Zn^(2+)and organic ion-pinned vanadium oxide can induce the high reversibility of Zn^(2+)insertion and extraction,thereby improving the cycle life.It is demonstrated that([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O cathodes deliver a discharge capacity of 181 mA h g^(-1)at8 A g^(-1)and ultra-long life span(99.5%capacity retention after 2000 cycles).A reversible Zn^(2+)/H^(+)ions(de)intercalation storage process and pseudocapacitive charge storage are characterized.The weaker interactions between organic ion and Zn^(2+)open a novel avenue for the design of highly reversible cathode materials with long-term cycling stability. 展开更多
关键词 [N(CH_(3))_(4) Zn]V_(8)O_(20)·3.8H_(2)O nanosheets aqueous zinc-ion battery highly reversible organic ion pre-intercalation zinc-carbon interactions
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Antioxidant effects of the orientin and vitexin in Trollius chinensis Bunge in D-galactose-aged mice 被引量:21
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作者 Fang An Guodong Yang +1 位作者 Jiaming Tian shuhua wang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第33期2565-2575,共11页
Total flavonoids are the main pharmaceutical components of Trollius chinensis Bunge, and orientin and vitexin are the monomer components of total flavonoids in Trollius chinensis Bunge. In this study, an aged mouse mo... Total flavonoids are the main pharmaceutical components of Trollius chinensis Bunge, and orientin and vitexin are the monomer components of total flavonoids in Trollius chinensis Bunge. In this study, an aged mouse model was established through intraperitoneal injection of D-galactose for 8 weeks, followed by treatment with 40, 20, or 10 mg/kg orientin, vitexin, or a positive control (vitamin E) via intragastric administration for an additional 8 weeks. Orientin, vitexin, and vitamin E improved the general medical status of the aging mice and significantly increased their brain weights. They also produced an obvious rise in total antioxidant capacity, superoxide dismutase, catalase, and glutathione peroxidase levels in the serum, and the levels of superoxide dismutase, catalase and glutathione peroxidase, Na+-K+-ATP enzyme, and Ca2+-Mg2+-ATP enzyme in the liver, brain and kidneys. In addition, they significantly reduced malondialdehyde levels in the liver, brain and kidney and lipofuscin levels in the brain. They also significantly improved the neuronal ultrastructure. The 40 mg/kg dose of orientin and vitexin had the same antioxidant capacity as vitamin E. These experimental findings indicate that orientin and vitexin engender anti-aging effects through their antioxidant capacities. 展开更多
关键词 Trollius chinesis Bunge orientin vitexin total flavonoids in Trollius
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NaOH/Urea Swelling Treatment and Hydrothermal Degradation of Waste Cotton Fiber 被引量:2
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作者 Lixia Gao Sheng Shi +3 位作者 Wensheng Hou shuhua wang Zhifeng Yan Chao Ge 《Journal of Renewable Materials》 SCIE EI 2020年第6期703-713,共11页
In this study,waste cotton fabric was used as cellulose raw material and pretreated in aqueous NaOH/urea solution system to investigate the effect of NaOH/urea pretreatment solution on the hydrolysis of cotton fiber.T... In this study,waste cotton fabric was used as cellulose raw material and pretreated in aqueous NaOH/urea solution system to investigate the effect of NaOH/urea pretreatment solution on the hydrolysis of cotton fiber.The cotton fiber was pretreated with different conditions of aqueous NaOH/urea solution,and the pretreated cotton fiber was hydrolyzed under the same conditions as the original cotton fiber.The results of characterization analysis showed that water retention value of pretreated cotton fiber was higher than that of unpretreated sample.Moreover,the cotton fiber presented both a convoluted structure and a coarser surface,XRD results suggested that the crystallinity degree of cellulose decreased dramatically,more cellulose II appeared,and the hydrogen bond is broken.Among the different pretreatment conditions,the pretreatment effect was the best when the reaction temperature was 0°C,the solid-liquid ratio was 2:50,and the NaOH/urea ratio was 7:12.The hydrolysis experiments of pretreated and unpretreated cotton fibers showed that when the hydrothermal temperature was 230°C,the heat preservation was 2 h,and the hydrochloric acid concentration was 5 wt.%,the glucose yield reached 29.99%.H+could catalyze the hydrolysis of cotton fiber more effectively due to damage to crystal structure and hydrogen bonds. 展开更多
关键词 Waste cotton fibers NaOH/urea PRETREATMENT hydrolyze recycling and reusing
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基于核心素养培养的高中地理生活化教学策略探究——以西北师大附中为例 被引量:8
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作者 王述华 《西北成人教育学院学报》 2022年第3期77-82,共6页
地理知识源于生活服务于生活,在地理课堂实施“生活化”教学,既符合学生的认知规律,又体现了我国高中地理新课标对培养学生核心素养的基本要求,同时凸显了地理学科注重社会实践、理论联系实际的特点。以西北师大附中为例,探讨在新课标... 地理知识源于生活服务于生活,在地理课堂实施“生活化”教学,既符合学生的认知规律,又体现了我国高中地理新课标对培养学生核心素养的基本要求,同时凸显了地理学科注重社会实践、理论联系实际的特点。以西北师大附中为例,探讨在新课标指引下从教材、教师、学生、社会等多个维度开发和利用生活化地理教学资源,以提升学生地理核心素养,实现地理教学的高效课堂。 展开更多
关键词 新课程改革 地理核心素养 高中地理 生活化教学
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LEARNING RATES OF KERNEL-BASED ROBUST CLASSIFICATION 被引量:1
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作者 王淑华 盛宝怀 《Acta Mathematica Scientia》 SCIE CSCD 2022年第3期1173-1190,共18页
This paper considers a robust kernel regularized classification algorithm with a non-convex loss function which is proposed to alleviate the performance deterioration caused by the outliers.A comparison relationship b... This paper considers a robust kernel regularized classification algorithm with a non-convex loss function which is proposed to alleviate the performance deterioration caused by the outliers.A comparison relationship between the excess misclassification error and the excess generalization error is provided;from this,along with the convex analysis theory,a kind of learning rate is derived.The results show that the performance of the classifier is effected by the outliers,and the extent of impact can be controlled by choosing the homotopy parameters properly. 展开更多
关键词 Support vector machine robust classification quasiconvex loss function learning rate right-sided directional derivative
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Feeding Effect of Growing-Finishing Pigs under Fine Division of Feeding Stages
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作者 Dongliang DUAN Xiumei MU +5 位作者 shuhua wang Jianghua DAN Xiaoliang CHENG Fulin JIAO Jinbao wang Hongzheng REN 《Asian Agricultural Research》 2017年第9期67-71,共5页
In order to study the feeding effect of fine division of feeding stages on the growing-finishing pigs,96 healthy Duroc × Landrace ×Yorkshire hybrid commercial pigs with similar age in days,size,and body weig... In order to study the feeding effect of fine division of feeding stages on the growing-finishing pigs,96 healthy Duroc × Landrace ×Yorkshire hybrid commercial pigs with similar age in days,size,and body weight about 15 kg,half boars and half sows,randomly divided into3 treatments( each treatment repeated 4 times,and each repetition 8 pigs). According to the body weight division standard,three stages,four stages,and five stages of feeding were adopted separately. The daily ration of with different nutrition levels was used,body weight and feed consumption were measured,and effects of different feeding methods on body weight increase,feed utilization,and economic benefits of growing-finishing pigs. The results showed that compared with the three-stage feeding,the body weight of five-stage and four-stage feeding increased by 4. 18%( P < 0. 01) and 2. 41%( P < 0. 05),respectively,and the body weight of five-stage feeding increased by 1. 74%( P < 0. 05) compared with that of four-stage feeding; the daily feed consumption of five-stage and four-stage feeding increased 3. 10%( P < 0. 01) and 1. 70%(P <0. 01),respectively,and the daily feed consumption of five-stage feeding was 1. 37% higher than that of four-stage feeding. The feed cost of five-stage feeding and four-stage feeding increased 3. 32%( P < 0. 01) and 1. 61%( P < 0. 05) separately,and the feed cost of five-stage feeding was 1. 69% higher than that of four-stage feeding( P < 0. 01). The income from average body weight increase of five-stage and fourstage feeding increased by 5. 47%( P < 0. 01) and 3. 59%( P < 0. 01) respectively,and the benefit of average body weight increase of fivestage feeding was 1. 81% higher than that of four-stage feeding( P > 0. 05). The crude protein consumption from average body weight increase of five-stage and four-stage feeding decreased by 2. 28%( P < 0. 01) and 1. 68%( P < 0. 01),respectively; the crude protein consumption from average body weight increase of five-stage feeding was 0. 67% lower than that of four-stage feeding; the feed conversion ratio of five-stage feeding,four-stage feeding,and three-stage feeding was 2. 92,2. 93,and 2. 95 respectively. The results showed that compared with the threestage feeding,the four-stage and five-stage feeding could significantly increase the body weight of the growing-finishing pigs,improve the feed utilization level and improve the economic benefits,and the effect of five-stage feeding was better than the four-stage feeding. 展开更多
关键词 Growing-finishing pigs Multi-stage feeding Body weight increasing degree Feed conversion ratio Income of average body weight increase Crude protein consumption from average body weight increase
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An Investigation into Typical English Language Use Tasks across Jobs by International Talents
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作者 shuhua wang Miao Hu +1 位作者 Chengli Zheng Ziyue Han 《教育研究前沿(中英文版)》 2020年第1期49-59,共11页
Along with the progress of economic globalization and the Belt and Road Initiative,there is a great need for international talents with global vision,knowledge of international rules and regulations,English language p... Along with the progress of economic globalization and the Belt and Road Initiative,there is a great need for international talents with global vision,knowledge of international rules and regulations,English language proficiency,and the ability to participate in international affairs and competitions.Through text analysis and interviews,this study collects typical English language use tasks in the workplace,and uses questionnaires to investigate the importance and difficulty of different tasks for English language users in different industries,positions and ranks,hence providing references for the design of English training and assessment tasks for international talents. 展开更多
关键词 International Talents Across Jobs Typical English Language Use Tasks Needs Analysis
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商务英语专业应用型人才培养模式改革与实践-以北京物资学院商务英语专业为例
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作者 王淑花 孙静波 路文军 《教育研究前沿(中英文版)》 2022年第3期104-108,共5页
为提升商务英语专业人才应用能力,地方性本科院校商务英语专业建设过程中应注重人才培养模式的内涵与特色,保证课程体系的设置能够支持人才培养目标,要建立有效的课程教学与学习效果的评价体系,以确保培养的商务英语专业人才能够满足区... 为提升商务英语专业人才应用能力,地方性本科院校商务英语专业建设过程中应注重人才培养模式的内涵与特色,保证课程体系的设置能够支持人才培养目标,要建立有效的课程教学与学习效果的评价体系,以确保培养的商务英语专业人才能够满足区域经济发展需求。 展开更多
关键词 商务英语专业 应用型人才 培养模式 内涵与特色 改革与实践
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Branch-Chain-Rich Diisopropyl Ether with Steric Hindrance Facilitates Stable Cycling of Lithium Batteries at-20°C
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作者 Houzhen Li Yongchao Kang +6 位作者 wangran Wei Chuncheng Yan Xinrui Ma Hao Chen Yuanhua Sang Hong Liu shuhua wang 《Nano-Micro Letters》 SCIE EI CAS 2024年第10期121-135,共15页
Li metal batteries(LMBs)offer signifi-cant potential as high energy density alternatives;nev-ertheless,their performance is hindered by the slow desolvation process of electrolytes,particularly at low temperatures(LT)... Li metal batteries(LMBs)offer signifi-cant potential as high energy density alternatives;nev-ertheless,their performance is hindered by the slow desolvation process of electrolytes,particularly at low temperatures(LT),leading to low coulombic efficiency and limited cycle stability.Thus,it is essential to opti-mize the solvation structure thereby achieving a rapid desolvation process in LMBs at LT.Herein,we introduce branch chain-rich diisopropyl ether(DIPE)into a 2.5 M Li bis(fluorosulfonyl)imide dipropyl ether(DPE)elec-trolyte as a co-solvent for high-performance LMBs at-20°C.The incorporation of DIPE not only enhances the disorder within the electrolyte,but also induces a steric hindrance effect form DIPE’s branch chain,excluding other solvent molecules from Li+solvation sheath.Both of these factors contribute to the weak interactions between Li^(+)and solvent molecules,effectively reducing the desolvation energy of the electrolyte.Consequently,Li(50μm)||LFP(mass loading~10 mg cm^(-2))cells in DPE/DIPE based electrolyte demonstrate stable performance over 650 cycles at-20°C,delivering 87.2 mAh g^(-1),and over 255 cycles at 25°C with 124.8 mAh g^(-1).DIPE broadens the electrolyte design from molecular structure considera-tions,offering a promising avenue for highly stable LMBs at LT. 展开更多
关键词 Solvation structure Li metal battery Low temperature Steric hindrance Disorder
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传统蜡染技艺的传承与保护研究——走访杨文斌先生的启示
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作者 王淑华 《民艺》 2020年第4期95-98,共4页
蜡染在我国流传悠久。具有鲜明的装饰艺术特色。近几年来,国内外不少手工爱好者进入贵州少数民族地区学习蜡染技艺,在云贵旅游景区及周边陆续出现了不少蜡染工作坊,蜡染服饰也开始走向了时尚舞台,传统手工艺大有复兴之势。然而传统蜡染... 蜡染在我国流传悠久。具有鲜明的装饰艺术特色。近几年来,国内外不少手工爱好者进入贵州少数民族地区学习蜡染技艺,在云贵旅游景区及周边陆续出现了不少蜡染工作坊,蜡染服饰也开始走向了时尚舞台,传统手工艺大有复兴之势。然而传统蜡染技艺的保护、传播与传承现状究竟如何,则需要对其应用和发展现状进行客观性探究,通过对杨文斌先生的走访,本文将试图从生态学与传播学的角度来进行传统蜡染技艺的现状性分析。 展开更多
关键词 传统蜡染 现状分析 传承与保护
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贵金属纳米颗粒的微生物合成 被引量:1
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作者 白睿 田晓春 +3 位作者 王淑华 严伟富 冮海银 肖勇 《化学进展》 SCIE CAS CSCD 北大核心 2019年第6期872-881,共10页
金属纳米颗粒在材料、催化、医学、环境等众多领域应用广泛,其中,金、银、铂、钯等贵金属的纳米颗粒作为良好的催化剂可提高反应的速率,因此,贵金属纳米颗粒的合成吸引了众多研究者的关注。传统的物理化学法虽能高效、可控地合成贵金属... 金属纳米颗粒在材料、催化、医学、环境等众多领域应用广泛,其中,金、银、铂、钯等贵金属的纳米颗粒作为良好的催化剂可提高反应的速率,因此,贵金属纳米颗粒的合成吸引了众多研究者的关注。传统的物理化学法虽能高效、可控地合成贵金属纳米颗粒,但是合成条件苛刻、成本昂贵、且会产生对环境有害的化学物质。因此,探索节能、环保、可持续的绿色合成方法成为纳米合成研究的热点之一。贵金属纳米颗粒的微生物合成法具备绿色合成技术的诸多要素,研究表明某些微生物能将金属盐转化成纳米材料,且微生物繁殖速度快、培养成本低、生长条件温和,从而得到了研究者们的广泛关注。本文归纳总结了目前微生物合成贵金属纳米颗粒的主要研究进展,包括贵金属纳米颗粒可能的合成机制以及尺寸与形貌控制方法,探讨了其在医学、催化、生物传感、环境方面的具体应用,并对贵金属纳米颗粒微生物合成的未来发展进行了展望。 展开更多
关键词 微生物 贵金属 纳米颗粒 生物合成 绿色化学
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Calcium ion pinned vanadium oxide cathode for high-capacity and long-life aqueous rechargeable zinc-ion batteries 被引量:2
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作者 Min Du Feng Zhang +5 位作者 Xiaofei Zhang Wentao Dong Yuanhua Sang Jianjun wang Hong Liu shuhua wang 《Science China Chemistry》 SCIE EI CAS CSCD 2020年第12期1767-1776,共10页
Rechargeable aqueous zinc ion batteries (ZIBs),with the easy operation,cost effectiveness,and high safety,are emerging candidates for high-energy wearable/portable energy storage systems.Unfortunately,the unsatisfacto... Rechargeable aqueous zinc ion batteries (ZIBs),with the easy operation,cost effectiveness,and high safety,are emerging candidates for high-energy wearable/portable energy storage systems.Unfortunately,the unsatisfactory energy density and undesired long-term cycling performance of the cathode hinder the development of ZIBs.Here,we report the chemical preintercalation of a small amount of calcium ions into V2O5 as the cathode material.The cathode of Ca0.04V2O5·1.74H2O (CVO)was demonstrated to have a high specific capacity of 400 mA h g^-1at the current density of 0.05 A g^-1and 187 mA h g^-1at 10 A g^-1,along with impressive capacity retention (100%capacity retention at 10 A g^-1 for 3,000 cycles).Meanwhile,the CVO//Zn battery exhibits a high energy density of 308 Wh kg^-1and a power density of 467 W kg^-1at 0.5 A g^-1.The superior performance originates from the pinning effect of the calcium ions and the lubricating effect of the structural water.The energy storage mechanism of the CVO cathode was also investigated in detail.The new phase (Zn3(OH)2V2O7·2H2O) generated upon cycling participates in the electrochemical reaction and thus contributes to the excellent electrochemical performance.The small amount of Ca^2+ pre-inserted into the interlayer of V2O5 sheds light on constructing cathodes with high energy density for ZIBs. 展开更多
关键词 aqueous zinc-ion battery ion pre-intercalation vanadium pentoxide phase transition energy storage mechanism
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Intracellular pH-responsive iron-catechin nanoparticles with osteogenic/anti-adipogenic and immunomodulatory effects for efficient bone repair 被引量:1
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作者 Ying Kong Feng Liu +11 位作者 Baojin Ma Wenhan wang Liang Li Xiaoying Xu Zhaoyang Sun Hongru Yang Yuanhua Sang Dong Li Gang Li Chao Liu shuhua wang Hong Liu 《Nano Research》 SCIE EI CSCD 2022年第2期1153-1161,共9页
Osteoimmunomodulation was identified as a new and important strategy to enhance osteogenic differentiation together with other osteogenic approaches.However,approaches regulating osteogenic differentiation and macroph... Osteoimmunomodulation was identified as a new and important strategy to enhance osteogenic differentiation together with other osteogenic approaches.However,approaches regulating osteogenic differentiation and macrophage polarization to remodel an osteoinductive microenvironment are separate and complicated.Therefore,the design and synthesis of one biomaterial that couples the osteogenic performance and immunomodulatory ability is a major challenge for efficient bone repair.In this study,self-assembled iron-catechin nanoparticles(Fe-cat NPs)were designed based on the coordinated reaction between iron ions and catechin and synthesized via a facile one-pot strategy.Interestingly,Fe-cat NPs show intracellular pH-responsive disassembly and release catechin molecules under the low pH of lysosomes after endocytosis.This strategy delivers catechin intracellularly and then enhances the osteogenic differentiation while inhibits the adipogenic differentiation of human adipose-derived stem cells(hADSCs).More importantly,Fe-cat NPs remodel the osteogenic immune microenvironment by resisting inflammation and promoting M2 polarization of macrophages.As a promising metal-organic nanodrug,the intracellular pH-responsive Fe-cat NPs significantly enhance the therapeutic effect of bone regneration by orchestrating osteogenic differentiation and immunomodulation,which may have great potential in bone tissue engineering. 展开更多
关键词 Fe-catechin nanoparticles osteogenesis ADIPOGENESIS IMMUNOMODULATION intracellular pH-responsive
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Oxygen vacancies and N-doping in organic–inorganic pre-intercalated vanadium oxide for high-performance aqueous zinc-ion batteries 被引量:1
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作者 Feng Zhang Min Du +7 位作者 Zhenyu Miao Houzhen Li Wentao Dong Yuanhua Sang Hechun Jiang Wenzhi Li Hong Liu shuhua wang 《InfoMat》 SCIE CAS 2022年第11期106-118,共13页
Pre-intercalation of metal ions into vanadium oxide is an effective strategy for optimizing the performance of rechargeable zinc-ion battery(ZIB)cathodes.However,the battery long-lifespan achievement and high-capacity... Pre-intercalation of metal ions into vanadium oxide is an effective strategy for optimizing the performance of rechargeable zinc-ion battery(ZIB)cathodes.However,the battery long-lifespan achievement and high-capacity retention remain a challenge.Increasing the electronic conductivity while simultaneously prompting the cathode diffusion kinetics can improve ZIB electrochemical performance.Herein,N-doped vanadium oxide(N-(Zn,en)VO)via defect engineering is reported as cathode for aqueous ZIBs.Positron annihilation and electron paramagnetic resonance clearly indicate oxygen vacancies in the material.Density functional theory(DFT)calculations show that N-doping and oxygen vacancies concurrently increase the electronic conductivity and accelerate the diffusion kinetics of zinc ions.Moreover,the presence of oxygen vacancies substantially increases the storage sites of zinc ions.Therefore,N-(Zn,en)VO exhibits excellent electrochemical performance,including a peak capacity of 420.5 mA h g^(-1)at 0.05 A g^(-1),a high power density of more than 10000 W kg^(-1)at 65.3 Wh kg^(-1),and a long cycle life at 5 A g^(-1)(4500 cycles without capacity decay).The methodology adopted in our study can be applied to other cathodic materials to improve their performance and extend their practical applications. 展开更多
关键词 aqueous zinc ion batteries cathode nitrogen doping organic–inorganic pre-intercalation oxygen vacancy
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Late Paleozoic-Early Mesozoic tectonic evolution of the Paleo-Asian Ocean: geochronological and geochemical evidence from granitoids in the northern margin of Alxa, Western China
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作者 Xin SHA Jinrong wang +4 位作者 Wanfeng CHEN Zheng LIU Xinwei ZHAI Jinlong MA shuhua wang 《Frontiers of Earth Science》 SCIE CAS CSCD 2018年第1期191-214,共24页
The Paleo-Asian Ocean (Southern Mongolian Ocean) ophiolitic belts and massive granitoids are exposed in the Alxa block, in response to oceanic subduction processes. In this work, we report petrographic, geochem- ica... The Paleo-Asian Ocean (Southern Mongolian Ocean) ophiolitic belts and massive granitoids are exposed in the Alxa block, in response to oceanic subduction processes. In this work, we report petrographic, geochem- ical, and zircon U-Pb age data of some granitoid intrusions from the northern Alxa. Zircon U-Pb dating for the quartz diorite, tonalite, monzogranite, and biotite granite yielded weighted mean 206pb/238U ages o f 302 ±9.2 Ma, 246.5±54.6 Ma, 235±4.4 Ma, and 229.5±5.6 Ma, respectively. The quartz diorites (-302 Ma) exhibit geochemical similarities to adakites, likely derived from partial melting of the initially subducted Chaganchulu back-arc oceanic slab. The tonalites (-246.5 Ma) display geochemical affinities of I-type granites. They were probably derived by fractional crystallization of the modified lithospheric mantle-derived basaltic magmas in a volcanic arc setting. The monzo- granites (-235 Ma) are characterized by low A1203, but high Y and Yb with notably negative Eu anomalies. In contrast, the biotite granites (-229.5 Ma) show high A1203 but low Y and Yb with steep HREE patterns and the absence of negative Eu anomalies. Elemental data suggested that the biotite granites were likely derived from a thickened lower crust, but the monzogranites originated from a thin crust. Our data suggested that the initial subduction of the Chaganchulu oceanic slab towards the Alxa block occurred at - 302 Ma. This subduction process continued to the Early Triassic (-246 Ma) and the basin was finally closed before the Middle Triassic (-235 Ma). Subsequently, the break-off of the subducted slab triggered asthenosphere upwelling (240-230 Ma). 展开更多
关键词 Paleo-Asian Ocean ALxa GRANITE geochemistry
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