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Sonochemical synthesis and characterization of magnetic separable Fe_(3)O_(4)-TiO_(2)nanocomposites and their catalytic properties

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International Journal of Smart and Nano Materials 2010年第4期1卷 278-287页

作者： wanquan jiang Xueping Zhang Xinglong Gong Fangfang Yan Zhong Zhang Department of Chemistry University of Science and Technology of China(USTC)Hefei 230026PR China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUSTCHefei 230027PR China National Center for Nanoscience and Technology Beijing 100080PR China

A novel sonochemical method is described for the preparation of Fe_(3)O_(4)–TiO_(2)photocatalysts in which nanocrystalline titanium dioxide particles are directly coated onto a magnetic *** Fe_(3)O_(4)nanoparticles were partially embedded in TiO_(2)***_(2)nanocrystallites were obtained by hydrolysis and condensation of titanium tetraisopropyl in the presence of ethanol and water under high-intensity ultrasound *** method is attractive since it eliminated the high-temperature heat treatment required in the conventional sol–gel method,which is important in transforming amorphous titanium dioxide into a photoactive crystalline *** comparison to other methods,the developed method is simple,mild,green and *** magnetization hysteresis loop for Fe_(3)O_(4)–TiO_(2)nanocomposites indicates that the hybrid catalyst shows superparamagnetic characteristics at room *** activity studies confirmed that the as-prepared nanocomposites have high photocatalytic ability toward the photodegradation of RhB ***,the photodecomposition rate decreases only slightly after six cycles of the photocatalysis ***,these Fe_(3)O_(4)–TiO_(2)nanocomposites can be served as an effective and conveniently recyclable photocatalyst.

关键词： sonochemical synthesis recyclable photocatalyst TiO_(2)nanocomposite rhodamine B degradation

Selection and application of four QTLs for grain protein content in modern wheat cultivars

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Journal of Integrative Agriculture 2024年第8期23卷 2557-2570页

作者： Zihui Liu Xiangjun Lai Yijin Chen Peng Zhao Xiaoming Wang wanquan Ji Shengbao Xu State Key Laboratory of Crop Stress Biology for Arid Areas/College of Agronomy Northwest A&F UniversityYangling 712100China

The grain protein content(GPC)is the key parameter for wheat grain nutritional *** study conducted a resampling GWAS analysis using 406 wheat accessions across eight environments,and identified four previously reported GPC *** analysis of 87 landraces and 259 modern cultivars revealed the loss of superior GPC haplotypes,especially in Chinese *** haplotypes were preferentially adopted in different agroecological zones and had broad effects on wheat yield and agronomic *** GPC QTLs did not significantly reduce yield,suggesting that high GPC can be achieved without a yield *** results of this study provide a reference for future GPC breeding in wheat using the four identified QTLs.

关键词： breeding grain protein content haplotype selection and application wheat

Trimethylamine oxide supplementation differentially regulates fat deposition in liver, longissimus dorsi muscle and adipose tissue of growing-finishing pigs

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Animal Nutrition 2024年第2期17卷 25-35页

作者： Andong Zha wanquan Li Jing Wang Ping Bai Ming Qi Peng Liao Bie Tan Yulong Yin Laboratory of Animal Nutritional Physiology and Metabolic Process Key Laboratory of Agro-ecological Processes in Subtropical RegionNational Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry ProductionInstitute of Subtropical AgricultureChinese Academy of Sciences University of Chinese Academy of Sciences College of Animal Science and Technology Hunan Agricultural University Yunnan Southwest Agriculture and Animal Husbandry Group Co. Ltd.

Trimethylamine oxide(TMAO) is a microbiota-derived metabolite, and numerous studies have shown that it could regulate fat metabolism in humans and mice. However, few studies have focused on the effects of TMAO on fat deposition in growing-finishing pigs. This study aimed to investigate the effect of TMAO on fat deposition and intestinal microbiota in growing-finishing pigs. Sixteen growing pigs were randomly divided into 2 groups and fed with a basal diet with 0 or 1 g/kg TMAO for 149 d. The intestinal microbial profiles, fat deposition indexes, and fatty acid profiles were measured. These results showed that TMAO supplementation had a tendency to decrease lean body mass(P < 0.10) and significantly increased backfat thickness(P < 0.05), but it did not affect growth performance. TMAO significantly increased total protein(TP) concentration, and reduced alkaline phosphatase(ALP) concentration in serum(P < 0.05). TMAO increased the a diversity of the ileal microbiota community(P < 0.05), and it did not affect the colonic microbial community. TMAO supplementation significantly increased acetate content in the ileum, and Proteobacteria and Escherichia-Shigella were significantly enriched in the TMAO group(P < 0.05). In addition, TMAO decreased fat content, as well as the ratio of linoleic acid, n-6polyunsaturated fatty acids(PUFA), and PUFA in the liver(P < 0.05). On the contrary, TMAO increased intramuscular fat content of the longissimus dorsi muscle, whereas the C18:2n6c ratio was increased,and the n-6 PUFA:PUFA ratio was decreased(P < 0.05). In vitro, 1 mmol/L TMAO treatment significantly upregulated the expression of FASN and SREBP1 in C2C12 cells(P < 0.05). Nevertheless, TMAO also increased adipocyte area and decreased the CPT-1B expression in subcutaneous fat(P < 0.05). Taken together, TMAO supplementation regulated ileal microbial composition and acetate production, and regulated fat distribution and fatty acid composition in growing-finishing pigs. These results

关键词： Growing-finishing pig Trimethylamine oxide Fat deposition Fatty acid composition Intestinal microbiota

Heat Transfer and Friction Characteristics of Printed Circuit Heat Exchangers with Different Channel Structures for S-CO_(2) Power System

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Journal of Thermal Science 2024年第3期33卷 1132-1147页

作者： jiang Tao LI Mingjia Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

Printed circuit heat exchanger(PCHE)has been widely used in supercritical carbon dioxide(S-CO_(2))power systems because of its high heat transfer efficiency and good ***,due to the large variety of PCHE configurations,channel selection in practical applications lacks a ***,this paper discussed the heat transfer and friction characteristics and the synergy of three fields in the channel under the guidance of the field synergy principle for four typical PCHE ***,the comprehensive performance of four channels was ***,the heat transfer and friction factor correlations for S-CO_(2)in four channels were *** findings demonstrate that the synergy of velocity and pressure fields of the straight channel PCHE is better(β≈180°),so its resistance loss is relatively *** zigzag and sinusoidal wavy channels and the airfoil fins can reduce the angle a between the temperature gradient and velocity,thus enhancing the heat *** sinusoidal wavy channel can reduce flow resistance compared to the zigzag channel due to the rounded *** streamlined airfoil structure can guide the flow and reduce backflow,thus reducing resistance *** the range of Re studied in this paper,the maximum error of the proposed heat transfer and friction factor correlations of PCHE is 7.0%,which shows good fitting *** research in this paper can provide a reference for the selection and design of PCHE with different channel configurations.

关键词： printed circuit heat exchanger supercritical carbon dioxide typical channel structure field synergy analysis

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang jiang Ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery

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Carbon Energy 2024年第7期6卷 14-25页

作者： Leijun Ye Weiheng Chen Zhong-Jie jiang Zhongqing jiang Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhouChina Department of Mechanical Engineering Ningbo University of TechnologyNingboChina Guangzhou Key Laboratory for Surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhouChina

Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma *** a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V *** hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported ***,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling ***-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics *** work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs.

关键词： heterojunction oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes

Hybrid rogue waves and breather solutions on the double-periodic background for the Kundu-DNLS equation

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Communications in Theoretical Physics 2024年第5期76卷 33-48页

作者： DongZhu jiang Zhaqilao College of Mathematics Science Inner Mongolia Normal UniversityHohhot 01022China Center for Applied Mathematical Science Inner MongoliaHohhot 010022China

In this paper,by using the Darboux transformation(DT)method and the Taylor expansion method,a new nth-order determinant of the hybrid rogue waves and breathers solution on the double-periodic background of the Kundu-DNLS equation is constructed when n is *** and rogue waves can be obtained from this determinant,*** to this,the hybrid rogue waves and breathers solutions on the different periodic backgrounds are given explicitly,including the single-periodic background,the double-periodic background and the plane wave background by selecting different *** addition,the form of the obtained solutions is summarized.

关键词： double-periodic background hybrid rogue waves and breather darboux transformation Kundu-DNLS equation

A newly unraveled 13.6-year oscillation from GPS displacements and its potential implications for the dynamic reference frame

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Science China Earth Sciences 2024年第10期67卷 3204-3212页

作者： Hao DING Weiping jiang School of Geodesy and Geomatics Hubei Luojia LaboratoryWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China

Numerous practical geodetic and geophysical applications necessitate precise measurements of GNSS displacements at the millimeter or sub-millimeter level. To attain such precision, it is imperative to identify and analyze the unidentified decadal signals inherent in the GPS displacements. In this research, we employ the optimal sequence estimation method to effectively detect an about 13.6-year oscillational signal with an excited amplitude of 3.6±1.2 mm in the U-components of the GPS displacements. It is noteworthy that this signal demonstrates a consistent spatial pattern characterized by the spherical harmonic Y_(2,-2). We conduct a comparative analysis with the 13.6-year oscillation observed in length-of-day variations(and geomagnetic records), finding that they are in reverse phase. After eliminating the Earth's external excitation sources through the utilization of two distinct in-situ hydrological records, we suggest that the 13.6-year GPS signal may come from the internal motions within the Earth. However, the specific excitation source and the detailed physical mechanism remain uncertain. Additionally, we develop a mathematical displacement model to explain the 13.6-year signal. Our findings indicate that this signal can result in displacements of up to 1.37 mm and velocity effects of 0.63 mm/yr(for U-component) at maximum. These results underscore the necessity of incorporating this 13.6-year signal into the construction and maintenance of a dynamic reference frame at the millimeter level.

关键词： GPS displacements Decadal changes 13.6-year oscillation Displacement model Dynamic reference frame

Capturing Plateau-Rayleigh instability in silver nanowires via ultrafast electron microscopy

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Nano Research 2024年第9期17卷 8402-8407页

作者： Shuai jiang Volkan Ortalan Department of Materials Science and Engineering University of ConnecticutStorrsCT 06269USA

Understanding the structural stability of nanomaterials such as nanowires is imperative for their practical ***,using single-shot ultrafast transmission electron microscopy,we captured the Plateau-Rayleigh instability behavior of silver nanowires decomposing into silver nanoparticles upon laser irradiation on nanosecond time *** found that this dynamic process can be accelerated by a factor of 10 through increasing the peak laser fluence from 6.03 to 14.60 mJ/cm^(2).Moreover,by comparing the laser fluence required to initiate the Plateau-Rayleigh instability in silver nanowires on carbon and Formvar membranes,it was found that the main driving force for the Plateau-Rayleigh instability in this study was substrate *** element analysis and molecular dynamics simulations are also applied to estimate the temperature jump of the nanowires and atomistic behavior,*** addition,the complex motions of silver nanowires under laser irradiation were systematically investigated by combining the results of ultrafast transmission electron microscopy with scanning electron microscopy characterizations and were determined to be related to nanowire-membrane interactions or pre-existing stresses on the nanowires,which in turn demonstrated the potential of ultrafast transmission electron microscopy for the characterization of nanomaterials and devices under extreme conditions.

关键词： silver nanowire Plateau-Rayleigh instability ultrafast transmission electron microscopy molecular dynamics simulation