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All-solid-state microscopic interferometer with frequency-variation and phase-shifting capability

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Optoelectronics Letters 2007年第2期3卷 123-125页

作者： TIAN jin-dong zhao Xiao-bo PENG Xiang Institute of Optoelectronics and Key laboratory of Optoelectronic Devices and Systems of Education Ministry Shenzhen Uuiversity Shenzhen 518060 China

A novel microscopic interferometry with ability of frequency-variation and phase-shifting is proposed for microstructures testing. By using acousto-optic technique, sequential carriers can be generated with different spatial frequencies so that the temporal phase unwrapping method can be applied for decoding the height information. Combined with phase-shifting technique realized by spatial light modulator, this method is especially suitable for interferometric measurement with high precision and large dynamic range.

关键词：全固态显微干涉仪频率变异相移能力显微结构测试

Natural products inspired[3+2]cycloaddition enables efficient construction of hydroxylated tetrahydrofuran acetals and concise syntheses of lignans

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Science China Chemistry 2024年第7期67卷 2306-2313页

作者： dong-Yue Cai Weiming Shi zhao-Hui jin Zhi-Xiang Yu jin-Xin zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China

Mimicking biosynthetic pathways of hongkonoids led to the development of a new Cu(Ⅰ)-catalyzed[3+2]cycloaddition ofα-hydroxyketone andβ-keto enol ethers,affording tetrahydrofuran acetals in a highly diastereoselective manner and 100%atom *** studies on the mechanism disclosed a concerted but asynchronous Michael addition/aldol *** the same importance,this methodology provides a practical biomimetic approach for one-step construction of the dibenzylbutyrolactol lignan backbone starting from two phenyl propane derivatives,opening up a powerful new approach for lignan synthesis,which is showcased by succinct total syntheses of two biologically important aryltetralin-type lignans,β-apopicropodophyllin and *** the mild and operationally simple conditions,the developed chemistry might have a promising prospect in potential industrial applications.

关键词： [3+2]cycloaddition transition-metal catalysis tetrahydrofuran lignans natural products

Effect of Photoperiod Treatments on Dormancy Induction and Changes in Correlated Respiratory Rate of Nectarine Peach Bud

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Agricultural Sciences in China 2008年第12期7卷 1445-1450页

作者： LI jin GAO dong-sheng zhao Kai YU Qin XU Chen-shan State Key Laboratory of Crop Biology College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an271018 P.R.China

The responses of dormancy induction to illumination and the characteristics of respiratory rate were studied with the nectarine peach bud in this article. The trial was conducted with nectarine （Prunus persica var. nectariana cv. Shuguang） and involved three treatments： a short day treatment （8 h）, a long day treatment （16 h）, and the normal condition as the control. The dormancy status was determined with the growth of shoot and the sprouting ability, and the respiratory rate was mensurated with oxygen electrode. Short day treatment could induce the growth stopping of peach shoots ahead, promote the development of dormancy, and induce buds into dormancy with 21 d previous to control. Long day treatment postponed the growth stopping and the induction and development of dormancy. The respiratory rate decreased according to the development of dormancy induction. The minimum respiratory rate appeared about 7 days after the start of dormancy induction. Bud respiratory rate increased during this period and then declined and remained at low level during dormancy period. Long day reduced buds respiratory rate slightly. Short day could induce dormancy obviously, and long day postponed dormancy induction. The changes of respiratory rate were correlated with the development of dormancy induction, and the bud respiratory rate was also affected by photoperiod.

关键词： peach dormancy induction photoperiod respiratory rate

Characterization of gut microbial and metabolite alterations in faeces of Goto Kakizaki rats using metagenomic and untargeted metabolomic approach

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World Journal of Diabetes 2023年第3期14卷 255-270页

作者： jin-dong zhao Min Sun Yan Li Chan-Juan Yu Ruo-dong Cheng Si-Hai Wang Xue Du zhao-Hui Fang Department of Endocrinology The First Affiliated Hospital of Anhui University of Chinese MedicineHefei 230031Anhui ProvinceChina Graduate School Anhui University of Chinese MedicineHefei 230012Anhui ProvinceChina School of Life Sciences Anhui UniversityHefei 230039Anhui ProvinceChina Department of Infectious Disease The First Affiliated Hospital of Anhui University of Chinese MedicineHefei 230031Anhui ProvinceChina

BACKGROUND In recent years,the incidence of type 2 diabetes(T2DM)has shown a rapid growth *** Kakizaki(GK)rats are a valuable model for the study of T2DM and share common glucose metabolism features with human T2DM patients.A series of studies have indicated that T2DM is associated with the gut microbiota composition and gut *** aimed to systematically characterize the faecal gut microbes and metabolites of GK rats and analyse the relationship between glucose and insulin *** To evaluate the gut microbial and metabolite alterations in GK rat faeces based on metagenomics and untargeted *** Ten GK rats(model group)and Wistar rats(control group)were observed for 10 wk,and various glucose-related indexes,mainly including weight,fasting blood glucose(FBG)and insulin levels,homeostasis model assessment of insulin resistance(HOMA-IR)and homeostasis model assessment ofβcell(HOMA-β)were *** faecal gut microbiota was sequenced by metagenomics,and faecal metabolites were analysed by untargeted *** metabolic pathways were evaluated based on the differential metabolites identified,and the correlations between blood glucose and the gut microbiota and metabolites were *** The model group displayed significant differences in weight,FBG and insulin levels,HOMA-IR and HOMA-βindexes(P<0.05,P<0.01)and a shift in the gut microbiota structure compared with the control *** results demonstrated significantly decreased abundances of Prevotella ***:604 and Lactobacillus murinus(P<0.05)and a significantly increased abundance of Allobaculum stercoricanis(P<0.01)in the model group.A correlation analysis indicated that FBG and HOMA-IR were positively correlated with Allobaculum stercoricanis and negatively correlated with Lactobacillus *** orthogonal partial least squares discriminant analysis suggested that the faecal metabolic profiles differed between the model and control *** pote

关键词： Type 2 diabetes mellitus Gut microbial Metabolites Goto-Kakizaki rats Metagenomics Untargeted metabolomics

Tuning mechanical and electrical performances of B_(4)C-TiB_(2)ceramics in a two-step spark plasma sintering process

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Journal of Advanced Ceramics 2024年第4期13卷 518-528页

作者： Jun zhao Xingshuo Zhang Zongning Ma dong Wang Xing jin Songlin Ran Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243002China Anhui Engineering Research Center for High Efficiency Intelligent Photovoltaic Module Chaohu UniversityHefei 238024China

B_(4)C–TiB_(2)is an advanced electrically conductive ceramic with excellent mechanical and electrical discharge machinable *** is challenging and rewarding to achieve highly conductive and hard B_(4)C–TiB_(2)composites at a minimum content of conductive TiB2 that has inferior hardness but double specific gravity of the B_(4)C matrix.A novel strategy was used to construct conductive networks in B_(4)C‒15 vol%TiB2 composite ceramics with B_(4)C,TiC,and amorphous B as raw materials by a two-step spark plasma sintering *** influences of particle size matching between B_(4)C and TiC on the conducting of the strategy and the microstructure were discussed based on the selective matrix grain growth *** mechanical and electrical properties were also systematically *** B_(4)C–15 vol%TiB2 composite ceramic prepared from 10.29µm B_(4)C and 0.05µm TiC powders exhibited a perfect three-dimensional interconnected conductive network with a maximum electrical conductivity of 4.25×10^(4)S/m,together with excellent mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 691±58 MPa,30.30±0.61 GPa,and 5.75±0.32 MPa·m^(1/2),respectively,while the composite obtained from 3.12µm B_(4)C and 0.8µm TiC powders had the best mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 827±35 MPa,32.01±0.51 GPa,and 6.45±0.22 MPa·m^(1/2),together with a decent electrical conductivity of 0.65×10^(4)S/m.

关键词： B_(4)C-TiB_(2) mechanical properties electrical conductivity conductive network

Effect of berberine on hyperglycaemia and gut microbiota composition in type 2 diabetic Goto-Kakizaki rats

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World Journal of Gastroenterology 2021年第8期27卷 708-724页

作者： jin-dong zhao Yan Li Min Sun Chan-Juan Yu Jia-Yun Li Si-Hai Wang Di Yang Cheng-Lin Guo Xue Du Wen-jin Zhang Ruo-dong Cheng Xiao-Chuan Diao zhao-Hui Fang Department of Endocrinology The First Affiliated Hospital of Anhui University of Chinese MedicineHefei 230031Anhui ProvinceChina Department of Infectious Diseases The First Affiliated Hospital of Anhui University of Chinese MedicineHefei 230031Anhui ProvinceChina School of Life Sciences Anhui UniversityHefei 230039Anhui ProvinceChina

BACKGROUND A recent investigation showed that the prevalence of type 2 diabetes mellitus(T2DM)is 12.8%among individuals of Han *** microbiota has been reported to play a central role in ***-Kakizaki(GK)rats show differences in gut microbiota compared to non-diabetic *** studies have indicated that berberine could be successfully used to manage *** sought to understand its hypoglycaemic effect and role in the regulation of the gut *** To determine whether berberine can regulate glucose metabolism in GK rats via the gut *** GK rats were acclimatized for 1 *** GK rats were randomly divided into three groups and administered saline(Mo),metformin(Me),or berberine(Be).The observation time was 8 wk,and weight,fasting blood glucose(FBG),insulin,and glucagon-like peptide-1(GLP-1)were *** tissue was observed for pathological ***,we sequenced the 16S rRNA V3-V4 region of the gut microbiota and analysed the *** Compared with the Mo group,the Me and Be groups displayed significant differences in FBG(P<0.01)and GLP-1(P<0.05).A significant decrease in weight and homeostatic model assessment-insulin resistance was noted in the Be group compared with those in the Me group(P<0.01).The pancreatic islets of the Me-and Be-treated rats showed improvement in number,shape,and necrosis compared with those of Mo-treated rats.A total of 580 operational taxonomic units were obtained in the three *** to the Mo group,the Me and Be groups showed a shift in the structure of the gut *** analysis indicated that FBG was strongly positively correlated with Clostridia_UCG-014(P<0.01)and negatively correlated with Allobaculum(P<0.01).Body weight showed a positive correlation with Desulfovibrionaceae(P<0.01)and a negative correlation with Akkermansia(P<0.01).Importantly,our results demonstrated that Me and Be could significantly decrease Bacteroidetes(P<0.01)and the Bac

关键词： Type 2 diabetes mellitus Amelioration of hyperglycaemia Modulation of gut microbiota Berberine Metformin Goto-Kakizaki rats

Directional amine-based solvent extraction for simultaneous enhanced water recovery,salt separation and effective descaling from hypersaline brines

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 83-92页

作者： Yuyao Zhang Litao Jia jin zhao Xuming Liu Shuyu dong Chuanyang Liu Yuanyuan Cui Shougang Research Institute of Technology Beijing 100043China Research Center of Environmental Technology in Water Pollution Source Identification and Precise Supervision School of EnvironmentTsinghua UniversityBeijing 100084China

The feasibility of simultaneous water recovery,salt separation and effective descaling of hypersaline brine was investigated by diisopropylamine(DIPA)-based directional solvent extraction(DSE),using diluted/concentrated seawater with initial saline concentration range of 12–237 g/L at extraction temperatures of 5 and 15℃,*** water recovery shows an obvious boundary at saline concentration of 115 g/L under dual effect of specific water extraction efficiency and extraction *** Cl^(–) ion concentration in product water is in sharp contrast to the nearly complete removal of SO_(4)^(2–)and hardness ions,indicating that DIPA-based DSE process indeed achieved efficient separation and purification of Cl^(–) ion from hypersaline ***,the radical precipitation of Mg^(2+)and Ca^(2+)ions in form of Mg(OH)_(2)and CaCO_(3)demonstrates effective descaling potential,although it leads to more DIPA residues in dewatered raffinate than product ***,an exponential correlation between the Cl^(–) removal efficiency and specific water extraction efficiency further reveals the intrinsic relationship of water extraction process and transfer of Cl^(–) ion to the product ***,the study provides a novel approach for integrating the water recovery and separation of Cl^(–) ion from ultra-high-salinity brines with radical precipitation of Mg^(2+)and Ca^(2+) ions in one step.

关键词： Hypersaline brines Directional solvent extraction Salt separation Ca^(2+)and Mg^(2+)descaling

Identification of reservoir types in deep carbonates based on mixedkernel machine learning using geophysical logging data

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Petroleum Science 2024年第3期21卷 1632-1648页

作者： jin-Xiong Shi Xiang-Yuan zhao Lian-Bo Zeng Yun-zhao Zhang Zheng-Ping Zhu Shao-Qun dong Key Laboratory of Exploration Technologies for Oil and Gas Resources of the Ministry of Education Yangtze UniversityWuhan4310HubeiChina School of Geosciences Yangtze UniversityWuhan430100HubeiChina College of Geosciences China University of Petroleum(Beijing)Beijing102249China Petroleum Exploration and Production Research Institute of SINOPEC Beijing100083China School of Earth Sciences and Engineering Xi'an Shiyou UniversityXi'an 710065ShaanxiChina

Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage *** cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging ***,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ***,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data *** address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,*** MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input *** particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD *** evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM ***,the built MKFD model was applied in a blind well test,and a variable importance analysis was *** comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger *** MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.

关键词： Reservoir type identification Geophysical logging data Kernel Fisher discriminantanalysis Mixedkernel function Deep carbonates

Resilient control of flexible hypersonic vehicles against unmatched distributed faults

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Chinese Journal of Aeronautics 2024年第5期37卷 60-70页

作者： dong zhao Wenjing REN School of Artificial Intelligence Anhui UniversityHefei 230601China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

This paper studies a robust fault compensation and vibration suppression problem of flexible hypersonic *** controlled plant is represented by a cascade system composed of a nonlinear Ordinary Differential Equation(ODE)and an Euler-Bernoulli Beam Equation(EBBE),in which the vibration dynamics is coupled with the rigid dynamics and suffers from distributed faults.A state differential transformation is introduced to transfer distributed faults to an EBBE boundary and a longitudinal dynamics is refined by utilizing T-S fuzzy IF-THEN rules.A novel T-S fuzzy based fault-tolerant control algorithm is developed and related stability conditions are *** robust exponential stability and well-posedness are proved by using the modified l_(0)-semigroup based Lyapunov direct approach.A simulation study on the longitudinal dynamics of flexible hypersonic vehicles effectively verifies the validity of the developed theoretical results.

关键词： Flexible hypersonic vehicles ODE-EBBE cascade Robust exponential stability Unmatched distributed fault compensation Vibration suppression