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Microstructure and Shear Properties Evolution of Minor Fe-Doped SAC/Cu Substrate Solder Joint under Isothermal Aging

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1279-1290页

作者： Quanzhen Li Chengming Li Xiaojing Wang Shanshan Cai Jubo Peng Shujin Chen Jiajun Wang Xiaohong Yuan Jiangsu University of Science and technology Zhenjiang212003China R&D center Yunnan Tin Group(Holding)Co.LtdKunming650000China The 58 Research Institute of China Electronics Technology Group CorporationWuxi214100China yunnan Precious Metals Lab Sino-Platinum Metals Co.LtdKunming650156China

Different amounts of Fe(0.005,0.01,0.03,0.05,and 0.07 wt%)were added to SAC305 to study the shear behavior damage of Fe-doped SAC solder joints under thermal loading(170℃,holding time of 0,250,500,and 750 h).The results show that during isothermal aging at 170℃,the average shear force of all solder joints decreases with increasing aging time,while the average fracture energy first increases and then decreases,reaching a maximum at 500 *** Fe doping could both increase shear forces and related fracture energy,with the optimum Fe doping amount being 0.03 wt%within the entire aging *** is because the doping Fe reduces the undercooling of the SAC305 alloy,resulting in the microstructure refining of solder *** in turn causes the microstructure changing from network structure(SAC305 joint:eutectic network+β-Sn)to a single matrix structure(0.03Fe-doped SAC305 joint:β-Sn matrix+small compound particles).Specifically,Fe atoms can replace some Cu in Cu_(6)Sn_(5)(both inside the solder joint and at the interface),and then form(Cu,Fe)_(6)Sn_(5) compounds,resulting in an increase in the elastic modulus and nanohardness of the ***,the growth of Cu_(6)Sn_(5) and Cu_(3)Sn intermetallic compounds(IMC)layer are inhibited by Fe doping even after the aging time prolonging,and Fe aggregates near the interface compound to form FeSn_(2).This study is of great significance for controlling the growth of interfacial compounds,stabilizing the microstructures,and providing strengthening strategy for solder joint alloy design.

关键词： SAC305 solder Fe doping Shear mechanical behavior Isothermal aging Interfacial intermetallic compounds(IMC)

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Detection and analysis of landslide geomorphology based on UAV vertical photogrammetry

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Journal of Mountain Science 2024年第4期21卷 1190-1214页

作者： BI Rui GAN Shu YUAN Xiping LI Kun LI Raobo LUO Weidong CHEN Cheng GAO Sha HU Lin ZHU Zhifu School of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China Plication Engineering Research center of Spatial Information Surveying and Mapping technology in Plateau and Mountainous Areas Set by Universities in yunnan Province Kunming 650093China West yunnan University of Applied Sciences Key Laboratory of Mountain Real Scene Point Cloud Data Processing and Application for Universities in Yunnan ProvinceDali 671006China

High-resolution landslide images are required for detailed geomorphological analysis in complex topographic environment with steep and vertical landslide *** study proposed a vertical route planning method for unmanned aerial vehicles(UAVs),which could achieve rapid image collection based on strictly calculated route *** effectiveness of this method was verified using a DJI Mavic 2 Pro,obtaining high-resolution landslide images within the Dongchuan debris flow gully,in the Xiaojiang River Basin,Dongchuan District,yunnan,China.A three-dimensional(3D)model was constructed by the structure-from-motion and multi-view stereo(SfM-MVS).Micro-geomorphic features were analyzed through visual interpretation,geographic information system(GIS),spatial analysis,and mathematical statistics *** results demonstrated that the proposed method could obtain comprehensive vertical information on landslides while improving measurement *** 3D model was constructed using the vertically oriented flight route to achieve centimeter-level accuracy(horizontal accuracy better than 6 cm,elevation accuracy better than 3 cm,and relative accuracy better than 3.5 cm).The UAV technology could further help understand the micro internal spatial and structural characteristics of landslides,facilitating intuitive acquisition of surface *** slope of landslide clusters ranged from 36°to 72°,with the majority of the slope facing east and *** elevation levels were relatively consistent while middle to lower elevation levels gradually decreased from left to right with significant variations in lower elevation *** the rainy season,surface runoff was abundant,and steep topography exacerbated changes in surface *** route method is suitable for unmanned aerial vehicle(UAV)landslide surveys in complex mountainous *** geomorphological analysis methods used will provide references for identifying and describing topographic

关键词： UAV Landslide Vertical route SfM-MVS Topographic features

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Moringa oleifera Lam. isothiocyanate inhibits lipid accumulation in high-fat diet mice by promoting lipid metabolism and modulating appetite

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Food Science and Human Wellness 2024年

作者： Jing Xie Zishan Hong Jiaying Mao Linjie Peng Yuying Bai Jun Sheng Yang Tian College of Food Science and technology， yunnan Agricultural University yunnan Provincial Key Laboratory of Precision Nutrition and Personalized Food Manufacturing， yunnan Agricultural University National Research and Development Professional center for Moringa Processing technology， yunnan Agricultural University Engineering Research center of Development and Utilization of Food and Drug Homologous Resources， Ministry of Education， yunnan Agricultural University yunnan Provincial Engineering Research center for Edible and Medicinal Homologous Functional Food， yunnan Agricultural University School of Tea and Coffee， Puer University

Obesity has brought great challenges to global human health， and how to effectively prevent and control the occurrence and development of obesity has become an urgent problem. The role and mechanism of 4-[(α-L-Rhamnosyloxy) benzyl] isothiocyanate (MITC)， an active ingredient of Moringa oleifera Lam.， in the regulation of lipid metabolism have not been comprehensively investigated. In the present study， we investigated the mechanism of MITC in inhibiting lipid accumulation in mice fed with a high-fat diet (HFD) in terms of both lipolysis and central appetite regulation mediated by the gut microbe–gut–brain axis. MITC enhanced the characteristic indices associated with HFD mice and also promoted adipocytolysis and brown fat thermogenesis. Moreover， MITC was observed to improve leptin resistance， modulate the composition of gut microbiota such as Ruminococcaceae， Parasutterella， and Acetatifactor， promote 5-HT secretion， further enhance the secretion of glucagon-like peptide-1 (GLP-1) and peptide tyrosine-tyrosine (PYY) to activate peroxisome proliferator-activated receptor (PPAR) signaling in the hypothalamus， and modulate feeding behavior to inhibit lipid accumulation in HFD mice. These data suggest that MITC supplementation can help to alleviate obesity or obesity-related diseases.

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Preparation of yttrium oxide coating with enhanced thermal shock resistance on refractories used for titanium alloy melting and casting

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Journal of Iron and Steel Research International 2024年第6期31卷 1411-1422页

作者： Ao Chen Yan Ma Zhou-fu Wang Hao Liu Xi-tang Wang Sen-na Chen Chen-xin Zhang Zi-yi Tang Wei-dong Fu Wei Cheng The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Xiangyang Juli High technology Material Co. Ltd.Xiangyang 441705HubeiChina Xiangyang Public inspection and Testing center Xiangyang 441000HubeiChina

In order to enhance the service life of refractories for melting and casting of titanium alloy,preparation of yttrium oxide coatings on the refractories surface is an effective *** improvement of thermal shock stability of the coating is beneficial to its spalling resistance during the high-temperature service,and the available slurry with good performance is the *** effects of the varieties and contents of dispersant(sodium tripolyphosphate,sodium hexametaphosphate,sodium pyrophosphate,citric acid and polycarboxylate ammonium salt)and binder(aluminum dihydrogen phosphate,zirconium acetate and yttria sol)on the stability,rheological and thixotropic properties of yttrium oxide waterbased slurry were investigated,and the effects of slurry composition design on the thermal shock resistance of the coating were *** results showed that the introduction of polycarboxylate ammonium salt as dispersant significantly improved the stability of the slurry,and the varieties of the binders had significant effects on the dispersibility of the *** aluminum dihydrogen phosphate and polycarboxylate ammonium salt were used as binder and dispersant,respectively,the slurry had better stability,suitable rheological and thixotropic *** using aluminum dihydrogen phosphate as binder,the coating had good thermal shock resistance and no obvious cracks were observed for the coating after thermal shock,which was attributed to the yttrium aluminate binding phase generated in the *** effective method was provided for preparing yttrium oxide coatings with enhanced thermal shock resistance applied in the process of titanium alloy melting and casting.

关键词： Yttrium oxide-Slurry Stability Rheological property Thixotropic property-Coating Thermal shock resistance

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A novel low molecular weight compound polysaccharides from Chinese herbal medicines: purification， characterization and anti-tumor activities in vitro and in vivo

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Food Science and Human Wellness 2024年

作者： Xu Yang Dongli Cao Haiyu Ji Huijing Xu Mengjie Xu Anjun Liu Key Laboratory of Food Nutrition and Safety， Ministry of Education， School of Food Science and Engineering， Tianjin University of Science and technology National center of inspection and Testing for Processed Food Quality， Tianjin Institute for Food Safety inspection technology

A novel low molecular weight polysaccharide (LMW-CPS) was identified from a specific combination of Chinese herb ingredients. The monosaccharide composition of LMW-CPS was consisted of single arabinose， which had an α-L-furanose configuration with an average molecular weight of 2.06 kDa. NMR spectra and monosaccharide constitution analyses revealed that it had a backbone of →5)-α-L-Araf-(1→ with α-L-Araf-(1→ as the terminal residue. In vitro experiments found that it could lead to apoptosis and inhibit hepatocellular carcinoma cell proliferation by arresting them in the S phase. In vivo experiments showed that it protected immune organs such as the thymus and spleen， enhanced immune cell activities， stimulated cytokine release， augmented the abundance of CD8， CD3， CD4， and CD19 positive lymphocytes， and markedly impeded solid hepatocellular carcinoma progression in mice. H&E staining and cell cycle examination also indicated that LMW-CPS arrested hepatocellular carcinoma cells at the S phase to induce apoptosis. These findings indicated its promising potential for the treatment of hepatocellular carcinoma.

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A FAS approach for stabilization of generalized chained forms: part 1. Discontinuous control laws

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Science China(Information Sciences) 2024年第2期67卷 118-143页

作者： Guang-Ren DUAN center for Control Theory and Guidance technology Harbin Institute of Technology center for Control Science and technology Southern University of Science and Technology

In this paper, a type of general nonholonomic systems is proposed, which contains both the Brockett’s two example systems, and their extended n-dimensional chained forms, as special cases. For the stabilization of such systems, a stabilizing controller is proposed based on the fully actuated system(FAS)approach, which is discontinuous at the origin but time-invariant when the open-loop system is time-invariant,and drives the feasible trajectories of the system to the origin exponentially. Furthermore, the proposed FAS approach is also extended to the sub-normal system case and the time-delay system case.

关键词： nonholonomic systems feedback stabilization exponential convergence sub-fully actuated systems time-delay systems

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Biosynthetic pathway of prescription cucurbitacin IIa and high-level production of key triterpenoid intermediates in engineered yeast and tobacco

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Plant Communications 2024年第6期5卷 154-172页

作者： Geng Chen Zhaokuan Guo Yanyu Shu Yan Zhao Lei Qiu Shaofeng Duan Yuan Lin Simei He Xiaobo Li Xiaolin Feng Guisheng Xiang Bo Nian Yina Wang Zhiyuan Li Chongkang Yang Yang Shi Yingchun Lu Guanze Liu Shengchao Yang Guanghui Zhang Bing Hao State Key Laboratory of Conservation and Utilization of Bio-resources in yunnan The Key Laboratory of Medicinal Plant Biology of Yunnan ProvinceNational&Local Joint Engineering Research Center on Germplasms Innovation&Utilization of Chinese Medicinal Materials in Southwest ChinaYunnan Agricultural UniversityKunming 650201China yunnan Characteristic Plant Extraction Laboratory KunmingYunnan 650106China

Cucurbitacin IIa is a triterpenoid isolated exclusively from Hemsleya plants and a non-steroidal anti-inflammatory drug that functions as the main ingredient of prescription Hemslecin capsules and tablets in *** biology provides new strategies for production of such valuable cucurbitacins at a large scale;however,the biosynthetic pathway of cucurbitacin IIa has been unknown,and the heterologous production of cucurbitacins in galactose medium has been expensive and low *** this study,we characterized the functions of genes encoding two squalene epoxidases(HcSE1-2),six oxidosqualene cyclases(HcOSC1-6),two CYP450s(HcCYP87D20 and HcCYP81Q59),and an acyltransferase(HcAT1)in cucurbitacin IIa biosynthesis by heterologous expression in Saccharomyces cerevisiae and Nicotiana *** achieved high-level production of the key cucurbitacin precursor 11-carbonyl-20b-hydroxy-Cuol from glucose in yeast via modular engineering of the mevalonate pathway and optimization of P450 expression *** resulting yields of 46.41 mg/l 11-carbonyl-20b-hydroxy-Cuol and 126.47 mg/l total cucurbitacin triterpenoids in shake flasks are the highest yields yet reported from engineered ***,production of 11-carbonyl-20b-hydroxy-Cuol by transient gene expression in tobacco resulted in yields of 1.28 mg/g dry weight in *** work reveals the key genes involved in biosynthesis of prescription cucurbitacin IIa and demonstrates that engineered yeast cultivated with glucose can produce high yields of key triterpenoid *** describe a low-cost and highly efficient platform for rapid screening of candidate genes and high-yield production of pharmacological triterpenoids.

关键词： cucurbitacin IIa oxidosqualene cyclase OSC 11-carbonyl-20b-hydroxy-Cuol Saccharomyces cerevisiae Nicotiana benthamiana Hemsleya chinensis

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Exploring the material basis and mechanism of Moringa oleifera in alleviating slow transit constipation based on network pharmacology and animal models

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Food Science and Human Wellness 2024年

作者： Sijin Li Xiaoyu Gao Kaifeng Guo Shuangfeng Liu Weiqian Yang Yan Zhao Jun Sheng Zhongbin Bai Yang Tian College of Food Science and technology， yunnan Agricultural University yunnan Key Laboratory of Precision Nutrition and Personalized Food Manufacturing， yunnan Agricultural University Department of Science and technology， yunnan Agricultural University College of Veterinary Medicine， yunnan Agricultural University Engineering Research center of Development and Utilization of Food and Drug Homologous Resources， Ministry of Education， yunnan Agricultural University

Moringa oleifera(M. oleifera) have laxative effects， but their active compositions and mechanisms are not very clear thus far. To this end， we systematically explored the active components and mechanism of M. oleifera leaves in relieving constipation by using the slow transit constipation (STC) mouse model and network pharmacology. The results of animal experiments showed that M. oleifera aqueous extract (MOA) had good laxative activity， and its 70% alcohol soluble part (ASP) also showed significant laxative activity(P < 0.01). Network pharmacological prediction results suggested that L-phenylalanine (Phe) was the key compound of ASP， and it might relieve constipation through tachykinin receptor 1 (TACR1) and three kinds of adrenergic receptors， including alpha-1a (ADRA1A)， alpha-2a (ADRA2A)， and alpha-2b (ADRA2B). Further animal experiment results showed that Phe significantly promoted gastrointestinal motility. Phe may relieve STC by enhancing the release of substance P (SP) and upregulating the mRNA expression of TACR1 in the ileum. Importantly， Phe may also promote intestinal movement by downregulating ADRA2A and ADRA2B and upregulating calmodulin and the mRNA and protein expression of myosin light chain 9 (MYL9) in the ileum， thereby activating the GPCR-MLC signaling pathway. These results lay a foundation for the application of M. oleifera and Phe in constipation.

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Gut microbiota modulating intestinal stem cell differentiation

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World Journal of Stem Cells 2024年第6期16卷 619-622页

作者： Lin He Chen Zhu Xiang-Feng Zhou Shu-E Zeng Le Zhang Kuan Li Department of Alcohol and Drug Dependence Treatment The Mental Hospital of Yunnan ProvinceKunming 650224Yunnan ProvinceChina Department of Physical Education Kunming Medical UniversityKunming 650500Yunnan ProvinceChina Department of Geriatric Psychiatry The Mental Hospital of Yunnan ProvinceKunming 650224Yunnan ProvinceChina Sleep Medicine center The Mental Hospital of Yunnan ProvinceKunming 650224Yunnan ProvinceChina

Proliferation and differentiation of intestinal stem cell(ISC)to replace damaged gut mucosal epithelial cells in inflammatory states is a critical step in ameliorating gut ***,when this disordered proliferation continues,it induces the ISC to enter a cancerous *** gut microbiota on the free surface of the gut mucosal barrier is able to interact with ISC on a sustained ***-biota metabolites are able to regulate the proliferation of gut stem and progenitor cells through transcription factors,while in steady state,differentiated colono-cytes are able to break down such metabolites,thereby protecting stem cells at the gut *** the future,the gut flora and its metabolites mediating the regulation of ISC differentiation will be a potential treatment for enteropathies.

关键词： Intestinal stem cells Gut microbiota Gut stem niche Microenvironment Probiotics

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Electrochemical and colorimetric dual-signal detection of Staphylococcus aureus enterotoxin B based on AuPt bimetallic nanoparticles loaded Fe-N-C single atom nanocomposite

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Food Science and Human Wellness 2024年第4期13卷 2025-2035页

作者： Huan Liang Hongcheng Liu Haojian Lin Guobao Ning Xiaokang Lu Siying Ma Fei Liu Hui Zhao Canpeng Li School of Chemical Science and technology Yunnan UniversityKey Laboratory of Medicinal Chemistry for Natural ResourceMinistry of EducationKunming 650091China Institute of Quality Standard and Testing technology Yunnan Academy of Agricultural ScienceSupervision and Testing Center for Farm Product QualityMinistry of AgricultureKunming 650223China State Key Laboratory of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and TechnologySchool of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China Laboratory for Conservation and Utilization of Bio-resource Yunnan UniversityKunming 650091China

Sensitive detection of Staphylococcus aureus enterotoxin B(SEB)is of importance for preventing food poisoning from threatening human *** this work,an electrochemical and colorimetric dual-signal detection assay of SEB was *** probe(Ab2/AuPt@Fe-N-C)was bound to SEB captured by Ab1,where the Ab2/AuPt@Fe-N-C triggered methylene blue degradation and resulted in the decrease of electrochemical ***,the probe catalyzed the oxidation of 3,3’,5,5’-tetramethyl biphenyl to generate a colorimetric absorbance at 652 *** the target was captured and formed a sandwich-like complex,the color changed from colorless to *** detection by colorimetric and electrochemical methods showed a linear relationship in the concentration ranges of 0.0002-10.0000 and 0.0005-10.0000 ng/mL,with limits of detection of 0.0667 and 0.1670 pg/mL,*** dual-signal biosensor was successfully used to detect SEB in milk and water samples,which has great potential in toxin detection in food and the environment.

关键词： Staphylococcus aureus enterotoxin Electrochemical immunosensor Colorimetric assay MOF@borophene composite Dual-functional Fe-N-C signal atom catalyst

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