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Re nanoclusters anchored on nanosheet supports: Formation of Re-O-matrix bonding and evaluation as all-pH-range hydrogen evolution reaction (HER) electrocatalysts

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Journal of Energy Chemistry 2022年第6期31卷 185-193,I0006页

作者： Shiyu Xu Hao Li Jeongbok Lee n.Clament Sagaya Selvam Baotao Kang jin yong Lee Pil J.yoo School of Chemical Engineering Sungkyunkwan UniversitySuwon 16419Republic of Korea Department of Chemistry Sungkyunkwan UniversitySuwon 16419Republic of Korea

Although the water splitting-based generation of hydrogen as an energy carrier can help to mitigate the global problems of energy shortage and climate change,the practical implementation of this strategy is hindered by the absence of inexpensive high-performance electrocatalysts for the hydrogen evolution reaction (HER).Re-based HER electrocatalysts exhibit predictable high performance within the entire pH range but suffer from arduous formation (i.e.,vulnerability to oxidation) and uncontrollable aggregation,which strongly discourages the maximisation of active site exposure required for activity *** overcome these limitations,we herein hydrothermally synthesise Re nanoclusters uniformly distributed on nanosheet supports,such as reduced graphene oxide nanosheets (Re nCs@rGO),revealing that this hybrid features abundant exposed active sites and high oxidation *** obtained electrocatalysts were elaborately characterized by microscopic and spectroscopic ***,density functional theory calculations confirm the optimised synthesis of Re nCs@rGO and indicate the crucial role of Re–O–C junction formation in securing *** effective suppression of Re nanocluster detachment/dissolution under HER conditions endows Re nCs@rGO with high electron conductivity and electrochemical stability,resulting in a durability superior to that of commercial Pt/C and an activity similar to that of this *** a result,Re nCs@rGO exhibited remarkably small HER overpotentials of 110,130,and 93 m V to deliver a current density of 10 mA cm^(-2) in 0.5 m H_(2)SO_(4),1 m PBS,and 1 m KOH,***,Re nCs@rGO is a promising alternative to conventional Pt-group-metal catalysts and should find applications in next-generation high-performance water splitting systems.

关键词： Hydrogen evolution reaction(HER) Hydrothermal synthesis Re nanoclusters nanosheet supports Electrocatalysts

Role of marine natural products in the development of antiviral agents against SARS‑CoV‑2:potential and prospects

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marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.P.nagahawatta n.m.Liyanage Thilina U.Jayawardena H.H.A.C.K.Jayawardhana Seong‑Hun Jeong Hyung‑Jun Kwon you‑jin Jeon Department of marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has surfaced and caused global concern owing to its ***-CoV-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World Health ***,the develop-ment of novel potent inhibitors against SARS-CoV-2 and future outbreaks is urgently *** naturally occurring bioactive substances have been studied in the clinical setting for diverse *** intricate infection and replication mechanism of SARS-CoV-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic *** natural products(mnPs)have received increased attention in the development of novel drugs owing to their high diversity and ***,this review article investigates the infection and replication mechanisms,including the function of the SARS-CoV-2 genome and ***,we highlighted anti-SARS-CoV-2 therapeutic intervention efforts utilizing mnPs and predicted SARS-CoV-2 inhibitor design.

关键词： SARS-CoV-2 marine natural products Drug targets Inhibitors

A new Phasor Estimator for PmU Applications:P Class and m Class

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Journal of modern Power Systems and Clean Energy 2020年第1期8卷 55-66页

作者： jose R.Razo-Hernandez Arturo mejia-Barron David Granados-Lieberman martin Valtierra-Rodriguez jose F.Gomez-Aguilar EnAP-Research Group Facultad de IngenieríaUniversidad Autónoma de Querétaro(UAQ)San CayetanoC.P.76807México EnAP-Research Group Departamento de Ingeniería ElectromecánicaInstituto Tecnológico Superior de Irapuato(ITESI)Colonia El CopalC.P.36821México COnACyT-Centro nacional de Investigación y Desarrollo Tecnológico(CEnIDET) Tecnológico Nacional de MéxicoInterior Internado Palmira S/NCol.PalmiraC.P.62490México

Phasor measurement units(PmUs)are fundamental tools in the applications of modern power systems,where synchronized phasor estimations are *** accuracy and dynamic performance requirements for phasor,frequency,and rate of change of frequency(ROCOF)estimations are established in the IEEE Std.C37.118.1-2011 along with the IEEE Std.C37.118.1 a-2014,where two PmU performances are suggested:P class filters for applications requiring fast response and m class filters for applications requiring high rejection to aliased *** this paper,a methodology to design new phasor estimators that satisfy the P class and m class requirements in PmUs is *** proposed methodology is based on finite impulse response filters,brick-wall filters,and complex filter design concepts,where frequency range,time performance,harmonic rejection and out-of-band interference requirements are considered in its design.A comparative analysis using the reference model given by the IEEE Std.C37.118.1 is *** results show the effectiveness of the phasor estimators under steady-state and dynamic conditions according to the PmU standard,making them suitable tools for applications in power systems.

关键词： Brick-wall filter complex filter IEEE Std.C37.118.1 m class P class phasor measurement unit(PmU) phasor estimator

Conductivity of the phloem in mango (mangifera indica L.)

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Horticulture Research 2021年第1期8卷 2045-2053页

作者： miguel Barcelo-Anguiano jose I.Hormaza Juan m.Losada Instituto de Hortofruticultura Subtropical y mediterranea La mayora(IHSm La mayora-CSIC-UmA) Avda Dr.Wienberg s/n.29750Algarrobo-CostaMalagaSpain

mango(mangifera indica L.,Anacardiaceae),the fifth most consumed fruit worldwide,is one of the most important fruit crops in tropical regions,but its vascular anatomy is quite *** studies examined the xylem structure in the stems of mango,but the anatomy of the phloem has remained elusive,leaving the long-distance transport of photoassimilates *** combined fluorescence and electron microscopy to evaluate the structure of the phloem tissue in the tapering branches of mango trees,and used this information to describe the hydraulic conductivity of its sieve tube elements following current models of fluid transport in *** revealed that the anatomy of the phloem changes from current year branches,where it was protected by pericyclic fibres,to older ones,where the lack of fibres was concomitant with laticiferous canals embedded in the phloem *** was present in the sieve plates,but also in the walls of the phloem sieve cells,making them discernible from other phloem cells.A scaling geometry of the sieve tube elements-including the number of sieve areas and the pore size across tapering branches-resulted in an exponential conductivity towards the base of the *** evaluations in mangofit with previous measurements of the phloem architecture in the stems of forest trees,suggesting that,despite agronomic management,the phloem sieve cells scale with the tapering *** pipe model theory applied to the continuous tubing system of the phloem appears as a good approach to understand the hydraulic transport of photoassimilates in fruit trees.

关键词： transport anatomy walls

Fingerprint Liveness Detection from Different Fingerprint materials Using Convolutional neural network and Principal Component Analysis

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Computers, materials & Continua 2017年第4期53卷 357-372页

作者： Chengsheng yuan Xinting Li Q.m.Jonathan Wu jin Li Xingming Sun School of Computer and Software Nanjing University of Information Science&TechnologyNing Liu RoadNo.219NanjingChina210044 Jiangsu Engineering Center of network monitoring Ning Liu RoadNo.219NanjingChina210044 Department of Electrical and Computer Engineering University of Windsor401 Sunset AvenueWindsorONCanada N9B 3P4 School of Computer Science Guangzhou UniversityYudongxi Road 36Tianhe DistrictGuangzhouChina510500

Fingerprint-spoofing attack often occurs when imposters gain access illegally by using artificial fingerprints,which are made of common fingerprint materials,such as silicon,latex,***,to protect our privacy,many fingerprint liveness detection methods are put forward to discriminate fake or true *** work on liveness detection for fingerprint images is focused on the construction of complex handcrafted features,but these methods normally destroy or lose spatial information between *** from existing methods,convolutional neural network(Cnn)can generate high-level semantic representations by learning and concatenating low-level edge and shape features from a large amount of labeled ***,Cnn is explored to solve the above problem and discriminate true fingerprints from fake ones in this *** reduce the redundant information and extract the most distinct features,ROI and PCA operations are performed for learned features of convolutional layer or pooling *** that,the extracted features are fed into SVm *** results based on the LivDet(2013)and the LivDet(2011)datasets,which are captured by using different fingerprint materials,indicate that the classification performance of our proposed method is both efficient and convenient compared with the other previous methods.

关键词： Fingerprint liveness detection Cnns PCA SVm ROI LivDet 2013 LivDet 2011

An Invasive Succulent Plant (Kalanchoe daigremontiana) Influences Soil Carbon and nitrogen mineralization in a neotropical Semiarid Zone

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Pedosphere 2018年第4期28卷 632-643页

作者： Ileana HERRERA jose R. FERRER-PARIS Diana BEnZO Saul FLORES Belkis GARCIA Jafet m. nASSAR Ecuela de Ciencias Ambientales Universidad Espiritu Santo Guayaquil 091650 (Ecuador) Centro de Ecologla Instituto Venezolano de Investigaciones Cientificas (IVIC) Caracas 1020 (Venezuela) Centro de Estudios Botdnieos y Agroforestales Instituto Venezolano de Investigaeiones Cientificas Maracaibo 4005 (Venezuela)

It has long been recognized that plant invasions may alter carbon （C） and nitrogen （n） cycles, but the direction and magnitude of such alterations have been rarely quantified. In this study, we quantified the effects caused by the invasion of a noxious exotic plant, Kalanchoe daigrernontiana （Crassulaceae）, on C and n mineralization and enzymatic and microbial activities in the soil of a semiarid locality in Venezuela. We compared soil parameters associated with these processes （C and n mineralization time and the cumulative values, fluorescein diacetate hydrolytic activity, and activities of dehydrogenase, β-glucosidase, glucosaminidase, and urease） between invaded and adjacent non-invaded sites. In addition, correlations among these parameters and the soil physical-chemical properties were also examined to determine if a positive feedback exists between nutrient availability and K. daigremontiana invasion. Overall, our results showed that C mineralization and transformation of organic compounds to nH4^＋ were favored at sites colonized by K. daigrernontiana. With this species, we found the highest cumulative amounts of nH4^＋-n and C and the lowest mineralization time. These results could be explained by higher activities of urease and glueosaminidase in soils under the influence of K. daigremontiana. In addition, higher amounts of organic matter and moisture content in invaded soils might favor C and n mineralization. In conclusion, invasion of neotropical semiarid zones by K. daigrernontiana may influence the chemical and biological properties of the soils covered by this species, increasing nutrient bioavailability, which, in time, can facilitate the invasion process.

关键词： Akaike Information Criterion C and n pools enzymatic activity nH4^+-n nO3^--n nutrient availability plant invasion

A Pull Back Theorem in the Adams Spectral Sequence

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Acta mathematica Sinica,English Series 2008年第3期24卷 471-490页

作者： jin Kun LIn School of mathematical Science and LPmC Nankai University Tianjin 300071 P. R. China

This paper proves that, for any generator x∈ExtA^s,tq（Zp,Zp）, if （1L ∧i）＊Ф＊（x）∈ExtA^s＋1,tq＋2q（H＊L∧m, Zp） is a permanent cycle in the Adams spectral sequence （ASS）, then b0x ∈ExtA^s＋1,tq＋q（Zp, Zp） also is a permenent cycle in the ASS. As an application, the paper obtains that h0hnhm∈ExtA^3,pnq＋p^mq＋q（Zp, Zp） is a permanent cycle in the ASS and it converges to elements of order p in the stable homotopy groups of spheres πp^nq＋p^mq＋q-3S, where p ≥5 is a prime, s ≤ 4, n ≥m＋2≥4 and m is the moore spectrum.

关键词： Adams spectral sequence Toda spectrum stable homotopy groups of spheres

Association between lifestyle factors and thyroid function in young euthyroid adults

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Food Science and Human Wellness 2024年第1期13卷 265-275页

作者： Elisa merchan-Ramirez Guillermo Sanchez-Delgado Lucas Jurado-Fasoli Francisco m Acosta manuel munoz-Torres jose m.Llamas-Elvira Jonatan R Ruiz Sport and Health University Research Institute(imUDS) Faculty of Sports ScienceUniversity of GranadaGranada 18016Spain Pennington Biomedical Research Center Baton Rouge 70808USA Faculty of medicine University of GranadaGranada 18071Spain Turku PET Centre University of TurkuTurku 20500Finland Turku PET Centre Turku University HospitalTurku 20520Finland Biosanitary Research Institute of Granada(Ibs.Granada) Granada 18012Spain CIBERFES Instituto de Salud CarlosⅢMadrid 28029Spain Endocrinology and nutrition Service University Hospital San CecilioGranada 18016Spain nuclear medicine Service "Virgen de las Nieves"University HospitalGranada 18014Spain

Purpose:The present work examines the associations of dietary habits,sedentarism,physical activity(PA)levels and sleep habits,with thyroid function in young euthyroid ***:A total of 105 young euthyroid adults participated in this cross-sectional *** function was determined in fasting conditions(>6 h).Dietary habits were measured by a food frequency questionnaire and three non-consecutive 24 h recalls,and different dietary intake and patterns were then *** time spent in sedentary,PA levels and sleep habits were objectively measured using a wrist-worn ***:Energy and carbohydrate intake were positively associated with thyroid stimulating hormone(TSH)(β=0.222;R^(2)=0.102;P=0.022 andβ=0.425;R^(2)=0.129;P=0.007,respectively)whereas fat intake was negatively associated with TSH(β=-0.428;R^(2)=0.137;P=0.004).Energy intake was also positively associated with free triiodothyronine(β=0.277;R^(2)=0.137;P=0.004).Further,adherence to the mediterranean diet was negatively related to TSH and free thyroxine(FT4)(β=-0.221;R^(2)=0.113;P=0.020 andβ=-0.268;R^(2)=0.071;P=0.007,respectively).Vigorous-intensity and overall PA were negatively associated with FT4(β=-0.227;R^(2)=0.052;P=0.022 andβ=-0.204;R^(2)=0.042;P=0.041,respectively).In contrast,no associations were found between sleep parameters and thyroid ***:Lifestyle factors such as dietary intake and PA levels seems to be related to thyroid function even in young euthyroid adults.

关键词： Thyroid hormones Dietary intake Sleep Physical activity Euthyroid

利用卫星测高、GRACE 和 GOCE 资料估计全球海洋表面地转流

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海洋学报 2014年第9期36卷 45-55页

作者：冯贵平金双根 jose m.Sanchez Reales 上海海洋大学海洋科学学院上海201306 中国科学院上海天文台上海200030 University of Alicante AlicanteSpain

重力恢复和气候试验 GRACE（gravity recovery and climate experiment）卫星极大地提高了地球重力场的精度和分辨率，特别是中长波分量，联合卫星测高数据可获得全球海洋表面大尺度洋流循环。另外，新一代地球重力和海洋环流探测卫星 G... 详细信息

重力恢复和气候试验 GRACE（gravity recovery and climate experiment）卫星极大地提高了地球重力场的精度和分辨率，特别是中长波分量，联合卫星测高数据可获得全球海洋表面大尺度洋流循环。另外，新一代地球重力和海洋环流探测卫星 GOCE（gravity field and steady-state ocean circulation explorer）于2009年3月成功发射，采用卫星重力梯度测量原理，对重力场的高频部分非常敏感，使其高分辨率监测全球海洋循环成为可能。本文利用1～7年 GRACE 观测数据确定的重力场模型和18个月 GOCE 观测数据确定的地球重力场模型 GO COnS GCF 2 TIm R3，联合卫星测高确定的平均海面高模型 mSS CnES CLS 11，分别估计全球海洋表面地转流，并且与实测浮标数据结果进行比较。分析表明 GOCE 重力卫星确定的重力场模型具有更高的空间分辨率，能够确定高精度和高空间分辨率的全球海洋地转流，如墨西哥湾暖流的细节和特征，并且与实测浮标结果基本一致。而基于1～4年 GRACE 观测资料的模型不能很好估计全球地转流特征，基于7年 GRACE 观测资料的重力场模型 ITG-Grace2010s 确定的全球地转流的精度仍低于18个月 GOCE 观测数据确定的地球重力场模型 GO COnS GCF 2 TIm R3的结果，估计的全球地转流仍含有较大的噪声，不能很好地反应中小尺度地转流细节特征。并计算 ITG Grace2010s 和 GOCE TIm3的稳态海面地形和全球平均地转流的内符合精度，结果显示，在全球范围内，GOCE TIm3的稳态海面地形和全球平均地转流的精度都比 ITG Grace2010s 结果的精度有着很大的改善，其中 ITG Grace2010s 的稳态海面地形的精度为21．6 cm，而 GOCE TIm3的结果则为7．45 cm，ITG Grace2010s 的全球平均地转流的精度为40．7 cm/s，而 GOCE TIm3的结果则为19．6 cm/s。

关键词：地转流卫星测高