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网络与信息安全学报 2024年第2期10卷 121-132页

作者：张天彭任志宇杜学绘王海超信息工程大学河南郑州450001

随着云计算、物联网技术的发展,可验证计算作为一种新兴的计算技术得到了广泛的应用。可验证计算在为用户带来便利的同时也存在着安全挑战:数据隐私性、结果可验证性和高效性。目前,矩阵乘法可验证计算方案基本采用稀疏矩阵相乘的加密... 详细信息

随着云计算、物联网技术的发展,可验证计算作为一种新兴的计算技术得到了广泛的应用。可验证计算在为用户带来便利的同时也存在着安全挑战:数据隐私性、结果可验证性和高效性。目前,矩阵乘法可验证计算方案基本采用稀疏矩阵相乘的加密方法来保护数据的隐私性。分析稀疏矩阵加密算法后,发现存在两个挑战:一是行或列公因子泄露原始矩阵行或列数据,二是零元素泄露原始矩阵零元素统计信息。同时,现有方案对云服务器计算结果的验证效率也不理想。针对数据隐私保护挑战,设计的批量矩阵乘法可验证计算方案利用三重扰动加密算法在不增加加解密计算复杂度的同时达到更强的隐私保护效果,其中,通过构造特殊的上或下三角稀疏矩阵加入双重扰动(乘法扰动和加法扰动)来保护行或列数据,通过构造特殊的加法稀疏矩阵加入单重扰动(加法扰动)来保护零元素信息。针对云服务器计算结果验证效率挑战,所提方案利用矩阵线性组合技术实现计算结果的批量验证,验证效率提高了约50倍,并随着矩阵数量的增多而提升。性能分析表明,所提方案基本没有增加客户端加解密开销,并提高了结果验证效率。

关键词：三重扰动线性组合隐私增强效率提升可验证计算

MgTiO3/MgTi2O5/TiO2 heterogeneous belt-junctions with high photocatalytic hydrogen production activity

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Nano Research 2017年第1期10卷 295-304页

作者： Ling Meng zhiyu ren Wei Zhou Yang Qu Guofeng Wang Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials ScienceHeilongjiang University Harbin 150080 China

An effective photocatalytic hydrogen production catalyst comprising MgTiO3/ MgTi2O5/TiO2 heterogeneous belt-junctions was prepared using magnesium ions by a thermally driven doping method. The tri-phase heterogeneous junction was confirmed by X-ray powder diffraction （XRD）, transmission electron microscopy （TEM）, and high-resolution TEM （HRTEM）. The as-prepared MgTiOg/MgTi2OJ TiO2 heterojunctions exhibited a very high photocatalytic hydrogen production activity （356.1 mol·g0.1mgcat·h^-1） and an apparent quantum efficiency （50.69% at 365 nm） that is about twice of that of bare TiO2 nanobelts （189.4mol·g0.1mgcat·h^-1）. Linear sweep voltage and transient photocurrent characterization as well as analysis of the electrochemical impedance spectra and Mott-Schottky plots revealed that the high photocatalytic performance is caused by the one-dimensional structure, which imparts excellent charge transportation characteristic, and the MgTiO3/MgTi2O5/TiO2 tri-phase heterojunction, which effectively drives the charge separation through the inherent electric field. This titanate-based tri-phase heterogeneous junction photocatalyst further enriches the catalyst system for photocatalytic hydrogen production.

关键词： MgTiO3/MgTi2O5/TiO2 heterogeneousbelt-junctions photocatalytic hydrogenproduction

Vertical α-FeOOH nanowires grown on the carbon fiber paper as a free-standing electrode for sensitive H2O2 detection

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Nano Research 2016年第8期9卷 2260-2269页

作者： Shichao Du zhiyu ren Jun Wu Wang Xi Honggang Fu Institute of Theoretical chemistry Jilin University ChangChun 130023 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

Highly sensitive, selective, and stable hydrogen peroxide （H2O2） detection using nanozyme-based catalysts are desirable for practical applications. Herein, vertical α-FeOOH nanowires were successfully grown on the surface of carbon fiber paper （CFP） via a low-temperature hydrothermal procedure. The formation of vertical α-FeOOH nanowires is ascribed to the structure-directing role of sodium dodecyl sulfate. The resulting free-standing electrode with one-dimensional （1D） nanowires offers oriented channels for fast charge transfer, excellent electrical contact between the electrocatalyst and the current collector, and good mechanical stability and reproducibility. Thus, it can serve as an efficient electrocatalyst for the reduction and sensitive detection of H2O2. The relation of the oxidation current of H202 with the concentration is linear from 0.05 to 0.5 mM with a sensitivity of -0.194 mA/（***2） and a low detection limit of 18μM. Furthermore, the portability in the geometric tailor and easy device fabrication allow extending the general applicability of this free-standing electrode to chemical and biological sensors.

关键词： α-FeOOH nanowires free-standing electrode synergistic effect electrocatalysis H2O2 detection

利用过渡金属氧化物调控金属铋纳米片的p轨道从而实现CO_(2)的高效电还原

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Science China Materials 2024年第6期67卷 1965-1974页

作者：尹伟勃刘博文王晓蕾王文倩宋子辰任志宇付宏刚 Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of ChinaSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China Key Laboratory of Superlight Materials and Surface Technology of Ministry of Education College of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China

p-d轨道之间的相互作用是一种提升电催化性能的有效方法.然而,其对主族金属的电催化CO_(2)还原(eCO_(2)RR)的增强机制尚不清晰.因此,我们向金属Bi纳米片中引入了一系列过渡金属氧化物(TMO:Fe_(2)O_(3)、Co_(3)O_(4)、NiO),并以此研究引... 详细信息

p-d轨道之间的相互作用是一种提升电催化性能的有效方法.然而,其对主族金属的电催化CO_(2)还原(eCO_(2)RR)的增强机制尚不清晰.因此,我们向金属Bi纳米片中引入了一系列过渡金属氧化物(TMO:Fe_(2)O_(3)、Co_(3)O_(4)、NiO),并以此研究引入TMO对Bi物种eCO_(2)RR性能的影响.根据原位傅里叶变换红外光谱(FTIR)和CO_(2)-程序升温脱附(TPD)的结果,Bi/TMO中的TMO可以增强CO_(2)的吸附和活化能力.密度泛函理论(DFT)计算结果表明,Bi活性位点^(*)OCHO吸附能及p轨道的优化可以降低CO_(2)到^(*)OCHO过程和^(*)OCHO到HCOOH过程的理论过电位.同时,由于Bi与TMO之间因复合而发生的电子重排也促进了催化剂与反应物之间的电子传输.因此,在热力学和动力学的双重作用下,Bi/TMO中的Bi活性位点表现出最佳的催化能力,在更宽的电位区间内实现了更高的催化活性和甲酸选择性.其中,Bi/Fe_(2)O_(3)的增强效果最为显著.在500 mV的宽电位区间内达到较高的甲酸的法拉第效率(>90%),在-0.8 VRHE时,甲酸的法拉第效率达到最大值99.7%(Bi的1.11倍),甲酸局部电流密度达到12.65 mA cm^(-2)(Bi的1.86倍).这一研究不仅建立了eCO_(2)RR性能增强与引入TMO之间的关系,也为理性设计高性能电催化剂提供了一条实用的、可扩展的途径.

关键词： transition metal oxides Bi/Fe_(2)O_(3)nanosheets elec-trocatalytic CO_(2)reduction HCOOH p-orbital regulation

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不同生根试剂对微型盆栽月季扦插生根的影响

中国农业科技导报 2024年第7期26卷 50-60页

作者：马力曹婷婷范又维任志雨刘春袁素霞中国农业科学院蔬菜花卉研究所北京100081 天津农学院园艺园林学院天津300384

微型盆栽月季具有重要的观赏价值。目前在国内栽培生产中,微型盆栽月季种苗工厂化生产程度低、质量良莠不齐,严重影响了其成品花的商品价值。研究微型盆栽月季的扦插繁育技术以提高微型盆栽月季种苗的质量在微型盆栽月季栽培生产中具有... 详细信息

微型盆栽月季具有重要的观赏价值。目前在国内栽培生产中,微型盆栽月季种苗工厂化生产程度低、质量良莠不齐,严重影响了其成品花的商品价值。研究微型盆栽月季的扦插繁育技术以提高微型盆栽月季种苗的质量在微型盆栽月季栽培生产中具有重要的实践意义。为分析不同生根试剂对4个微型盆栽月季品种扦插生根的影响,设置不同水平的中蔬根保201、吲哚-3-丁酸(indole-3-butyric acid,IBA)、萘乙酸(1-naphthlcetic acid,NAA)、2,4-二氯苯氧乙酸(2,4-Dichlorophenoxyacetic acid,2,4-D)溶液以及部分试剂组合为生根试剂处理,并以清水(CK1)和公司常用试剂处理(CK2,由紫玉花卉产业有限公司提供的生根粉剂)为对照,利用主成分分析法对各品种扦插苗根系性状指标进行综合评价,以筛选扦插繁殖的最佳生根试剂。结果表明,在单一生根试剂处理中,CK2处理在所有品种均表现较优,能有效促进根系生长;另外,IBA和中蔬根保201溶液对扦插苗根系的生长发育也具有很好的促进作用,且它们的组合处理对所有供试品种的扦插苗根系生长发育也均有很好的促进效果,优于CK2。其中,0.67 mL·L^(-1)的中蔬根保201溶液与1500 mg·L^(-1)的IBA溶液的混合液处理所有品种扦插苗的根系生长情况都非常优异。

关键词：微型盆栽月季扦插繁殖生根试剂根系生长发育

Tunable metamaterial absorber based on resonant strontium titanate artificial atoms

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Journal of Materials Science & Technology 2021年第3期62卷 249-253页

作者： Xiaoming Liu zhiyu ren Tian Yang Luping Chen Qiang Wang Ji Zhou Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819China Department of New Energy Science&Engineering School of MetallurgyNortheastern UniversityShenyang110819China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China

Dynamic control of the absorption frequency and intensity of metamaterial absorbers has attracted considerable attention,and many kinds of tunable metamaterial absorbers have been ***,due to the integration of separate resonant unit and tunable unit,these designed metamaterial absorbers suffer from complex structure and low *** numerically and experimentally demonstrate a tunable metamaterial absorber composed of artificial dielectric atoms as both resonant and tunable unit arrayed periodically in the background matrix on the metallic *** insensitive and wide incident angle absorption band with simulated and experimental absorptivity of 99%and 96%at 9.65 GHz are achieved at room *** absorption frequency can be gradually modulated by temperature,however,the absorption intensity at working frequency remains near *** dielectric atoms based tunable metamaterial absorbers with simple structure have potential applications as tempe rature sensors and frequency selective thermal emitters.

关键词： unity Tunable metamaterial absorber based on resonant strontium titanate artificial atoms

Co-vacancy-rich CO1-xS nanosheets anchored on rGO for high-efficiency oxygen evolution

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Nano Research 2017年第5期10卷 1819-1831页

作者： Jiaqing Zhu zhiyu ren Shichao Du Ying Xie Jun Wu Huiyuan Meng Yuzhu Xue Honggang Fu Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China

Developing cost-efficient electrocatalysts for oxygen evolution is vital for the viability of H2 energy generated via electrolytic water. Engineering favorable defects on the electrocatalysts to provide accessible active sites can boost the sluggish reaction thermodynamics or kinetics. Herein, Col_xS nanosheets were designed and grown on reduced graphene oxide （rGO） by controlling the successive two-step hydrothermal reaction. A belt-like cobalt-based precursor was first formed with the assistance of ammonia and rGO, which were then sulfurized into Col_xS by L-cysteine at a higher hydrothermal temperature. Because of the non-stoichiometric defects and ultrathin sheet-like structure, additional cobalt vacancies （V^o） were formed/exposed on the catalyst surface, which expedited the charge diffusion and increased the electroactive surface in contact with the electrolyte. The resulting Col_xS/rGO hybrids exhibited an overpotential as low as 310 mV at 10 ***-2 in an alkaline electrolyte for the oxygen evolution reaction （OER）. Density functional theory calculations indicated that the Vco on the Col_xS/rGO hybrid functioned as catalytic sites for enhanced OER. They also reduced the energy barrier for the transformation of intermediate oxygenated species, promoting the OER thermodynamics.

关键词： cobalt vacancies (Vco) Co1-xS oxygen evolution reaction electrocatalysis nanosheets

In-situ structure reconstitution of NiCo2Px for enhanced electrochemical water oxidation

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科学通报：英文版 2017年第22期62卷 1510-1518页

作者： Xue Bai zhiyu ren Shichao Du Huiyuan Meng Jun Wu Yuzhu Xue Xiaojun Zhao Honggang Fu Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry Ministry of Education of the People's Republic of China Tianjin Normal University Tianjin 300387 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

Gaining insight into the structure evolution of transition-metal phosphides during anodic oxidation is significant to understand their oxygen evolution reaction(OER) mechanism, and then design highefficiency transition metal-based catalysts. Herein, NiCo_2P_x nanowires(NWs) vertically grown on Ni foam were adopted as the target to explore the in-situ morphology and chemical component reconstitution during the anodic oxidation. The major factors causing the transformation from NiCo_2P_x into the hierarchical NiCo_2P_x@CoNi(OOH)_x NWs are two competing reactions: the dissolution of NiCo_2P_x NWs and the oxidative re-deposition of dissolved Co^(2+) and Ni^(2+) ions, which is based primarily on the anodic bias applied on NiCo2 Px NWs. The well balance of above competing reactions, and local pH on the surface of NiCo_2P_x NW modulated by the anodic oxidation can serve to control the anodic electrodeposition and rearrangement of metal ions on the surface of NiCo_2P_x NWs, and the immediate conversion into CoNi(OOH)_x. Consequently, the regular hexagonal CoNi(OOH)_x nanosheets grew around NiCo_2P_x *** from the active catalytic sites on the surface and the sufficient conductivity, the resultant NiCo_2P_x@CoNi(OOH)_x arrays also display good OER activity, in terms of the fast kinetics process, the high energy conversion efficiency, especially the excellent durability. The strategy of in-situ structure reconstitution by electrochemical reaction described here offers a reliable and valid way to construct the highly active systems for various electrocatalytic applications.

关键词： NiCo2Px Structure reconstitution Anodic oxidation CoNi(OOH)x Oxygen evolution reaction(OER)

Interconnected 1D Co3O4 nanowires on reduced graphene oxide for enzymeless H2O2 detection

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Nano Research 2015年第2期8卷 469-480页

作者： Lingjun Kong zhiyu ren Nannan Zheng Shichao Du Jun Wu Jingling Tang Honggang Fu Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China Department of Pharmaceutics School of Pharmacy Harbin Medical University Harbin 150086 China

Enzymeless hydrogen peroxide （H2O2） detection with high sensitivity and excellent selectivity is desirable for clinical diagnosis. Herein, one-dimensional Co3O4 nanowires have been successfully constructed on reduced graphene oxide （rGO） via a simple hydrothermal procedure and subsequent thermal treatment. These Co3O4 nanowires, assembled by small nanoparticles, are interlaced with one another and make a spider web-like structure on rGO. The formation of Co3O4-rGO hybrids is attributed to the structure-directing and anchoring roles of DDA and GO, respectively. The resulting structure possesses abundant active sites, the oriented transmission of electrons, and unimpeded pathways for matter diffusion, which endows the Co3O4-rGO hybrids with excellent electrocatalytic performance. As a result, the obtained Co3O4-rGO hybrids can serve as an efficient electrochemical catalyst for H2O2 oxidation and high sensitivity detection. Under physiological conditions, the oxidation current of H2O2 varies linearly with respect to its concentration from 0.015 to 0.675 mM with a sensitivity of 1.14 ***^-***^-2 and a low detection limit of 2.4 μM. Furthermore, the low potential （-0.19 V） and the good selectivity make Co3O4-rGO hybrids suitable for monitoring H2O2 generated by liver cancer HepG2 cells. Therefore, it is promising as a non-enzymatic sensor to achieve real-time quantitative detection of H2O2 in biological applications.

关键词： interconnected nanowires Co3O4-rGO hybrids synergistic effect electrocatalysis enzymeless H2O2 detection