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Flavonoids from Litchi(Litchi chinensis Sonn.) Seeds and Their Inhibitory Activities on α-Glucosidase

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Chemical Research in Chinese Universities 2013年第4期29卷 682-685页

作者： REN Shen XU duo-duo GAO yang MA Yu-ting GAO Qi-pin Research and Development Center Changehun University of Traditional Chinese Medicine Changchun130117 P. R. China College of Traditional Chinese Medicine Jilin Agricultural University Changehun130118 P R. China

With the bioactivity-guided method,a new flavanone glycoside,together with nine known flavonoids were isolated from 50% aqueous ethanol of litchi（Litchi chinensis Sonn.） *** chemical structure of the new compound was elucidated via 1D and 2D nuclear magnetic resonance（NMR） techniques and mass spectrometry to be （2S）-pinocembrin-7-O-（6＂-O-α-L-arabinosyl-β-D-glucopyranoside）（1）,and the nine known compounds were determined to be quercetin（2）,phlorhizin（3）,pinocembrin-7-O-glucoside（4）,kaempferol-7-O-β-D-glucopyranoside（5）,onychin（6）,nairutin（7）,narcissin（8）,pinocembrin-7-O-[（6＂-O-β-D-glucopyranoside）-β-D-glucopyranoside]（9） and pinocembrin-7-O-[（2＂,6＂-di-O-α-L-rhamnopyranosyl）-β-D-glucopyranoside]（10）.Some of the isolated flavonoids were tested for their inhibitory effects on α-*** compounds 2 and 3 showed stronger inhibitory activity than positive control.

关键词： Litchi chinensis Sonn.seed Flavanoid Inhibitory activity α-Glucosidase

Applications of the CE/SE Scheme to Incompressible Viscous Flows in Two-Sided Lid-Driven Square Cavities

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Chinese Physics Letters 2012年第8期29卷 176-180页

作者： yang duo-Xing ZHANG De-Liang Institute of Crustal Dynamics Chinese Earthquake AdministrationBeijing 100085 LHD Institute of MechanicsChinese Academy of SciencesBeijing 100190

The spacetime conservation element-solution element(CE/SE)method is extended to two-dimensional incompressible viscous flow in a two-sided lid-driven square *** on the SIMPLE method concept,the preconditioned dual-time scheme is introduced for unsteady *** CE/SE-based code is validated by simulating one-sided lid-driven cavity *** two-sided lid-driven square cavity problem involves several interesting characteristics being successfully predicted,including development of a pair of off-corner vortices and a free shear layer in the case of parallel wall motion,as well as the appearance of corner vortices for lower Reynolds numbers in the case of anti-parallel motion of the *** is found that both the Reynolds number and the direction of the moving walls affect the fluid flow in the cavity.

关键词： sided walls Reynolds

Spray Deposition Behavior and Numerical Simulation of Growth of Tubular Preform in Spray Forming Process

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Journal of Iron and Steel Research International 2012年第2期19卷 28-35页

作者： XIANG Jin-zong ZHANG Yin FAN Wen-jun WANG Ping HE you-duo Inner Mongolia Key Laboratory for Utilization of Bayan Obo Multi-Metallic Resources： Elected State KeyLaboratory Inner Mongolia University of Science and Technology Baotou 014010 Inner Mongolia China Anhui Shoukuang-Dachang Metal Materials Co Ltd Luran 237400 Anhui China

Analysis on the deposition behavior of spray on deposition surface was made and an optimization method for the movement parameters （u, ω） of substrate was obtained. Simultaneously, a mathematical model of growth of tubular preform, specifically aimed at the kind of atomizer that is fixed and with a tilt angle was established. By in- tegrating the optimization method and the mathematical model, the growth process and shape of preform were simu- lated. The results show that the tilt angle of atomizer plays an important role on the dimensions and shapes of tubular preforms and it can provide a guidance for the development of spray forming equipment.

关键词： spray deposition behavior parameters optimization tubular preform~ growth process

A Theoretical Investigation into the Orientation of Buckling Direction of the Reinforcing Fibers in EMC Laminate

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Journal of Wuhan University of Technology(Materials Science) 2014年第1期29卷 148-153页

作者：熊志远 JIN Dafeng yang Yongbao ZENG duo State Key Laboratory of Automotive Safety and Energy Department of Automotive Engineering Tsinghua University

Due to its high packaging strain and shape memory effect, elastic memory composite （EMC） has considerable potential application in future deployable space structures. Buckling of the reinforcing fibers is the primary deformation mechanism of such a new class of functional materials to realize a higher folding strain than that of conventional fiber reinforced composites. In this paper, the orientation of buckling direction of the reinforcing fibers in EMC laminate will be theoretically analyzed to better understand such deformation mechanism. The results reveal that the bucking protruding from the edge produces the lower energy needed for EMC laminate.

关键词： elastic memory composite buckling direction folding reinforcing fiber

Habitat quality assessment of mining cities based on InVEST model—a case study of Yanshan County,Jiangxi Province

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International Journal of Coal Science & Technology 2022年第2期9卷 245-254页

作者： Yanan Li Linghua duo Ming Zhang Jingyuan yang Xiaofei Guo Research Center of Geological Resource Economics and Management East China University of TechnologyNanchang 30013China Faculty of Geomatics East China University of TechnologyNanchang 30013China

The assessment of the spatiotemporal evolution of habitat quality caused by land use changes can provide a scientifc basis for the ecological protection and green development of mining *** Yanshan County as an example of a typical mining city,this article discussed the spatial pattern and evolution characteristics of habitat quality in 2000 and 2018 based on the ArcGIS platform and the InVEST *** conclusions are as below:from 2000 to 2018,the area of farmland and construction land changed the most in the study *** them,the area of farmland decreased by 3.48%,and the area of industrial and mining land and construction land increased by 53.25%.Areas of low,relatively low and high habitat quality expanded,and areas of medium and relatively high habitat quality shrank,which is closely related to the distribution of land *** areas with high habitat degradation degrees appear around cities,mining areas and watersheds,while the areas with low habitat degradation degrees are mainly distributed in the southern *** distribution of cold and hot spots in the habitat quality distribution of Yanshan County presents a pattern of“hot in the south and cold in the north”.The results are of great signifcance to the precise implementation of ecosystem management decisions in mining cities and the creation of a landscape pattern of“beautiful countrysides,green cities,and green mines”.

关键词： InVEST model Habitat quality Land use change Temporal and spatial pattern Mining city

Mitochondrial malic enzyme 2 promotes breast cancer metastasis via stabilizing HIF-1α under hypoxia

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Chinese Journal of Cancer Research 2021年第3期33卷 308-322页

作者： duo you Danfeng Du Xueke Zhao Xinmin Li Minfeng Ying Xun Hu Cancer Institute(Key Laboratory for Cancer Intervention and Prevention China National Ministry of EducationZhejiang Provincial Key Laboratory of Molecular Biology in Medical Sciences)The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China State Key Laboratory of Esophageal Cancer Prevention&Treatment and Henan Key Laboratory of Esophageal Cancer Research of the First Affiliated Hospital Zhengzhou UniversityZhengzhou 450000China Department of Pathology Women and Infants Hospital of ZhengzhouZhengzhou 450000China

Objective: α-ketoglutarate(α-KG) is the substrate to hydroxylate collagen and hypoxia-inducible factor-1α(HIF-1α), which are important for cancer metastasis. Previous studies have shown that the upregulation of collagen prolyl 4-hydroxylase in breast cancer cells stabilizes the expression of HIF-1α by depleting α-KG levels. We hypothesized that mitochondrial malic enzyme 2(ME2) might also affect HIF-1α expression via modulating α-KG levels in breast cancer ***: We evaluated ME2 protein expression in 100 breast cancer patients using immunohistochemistry and correlated with clinicopathological indicators. The effect of ME2 knockout on cancer metastasis was evaluated using an orthotopic breast cancer model. The effect of ME2 knockout or knockdown on the levels of α-KG and HIF-1α proteins in breast cancer cell lines was determined both in vitro and in ***: ME2 was found to be upregulated in the human breast cancerous tissues compared with the matched precancerous tissues(P<0.001). The elevated expression of ME2 was associated with a poor prognosis(P=0.019).ME2 upregulation was also related to lymph node metastasis(P=0.016), pathological staging(P=0.033), and vascular cancer embolus(P=0.014). Also, ME2 knockout significantly inhibited lung metastasis in vivo. In the tumors formed by ME2 knockout cells, the levels of α-KG were significantly increased and collagen hydroxylation level did not change significantly but HIF-1α protein expression was significantly decreased, compared to the control samples. In cell culture, cells with ME2 knockout or knockdown demonstrated significantly higher α-KG levels but significantly lower HIF-1α protein expression than control cells under hypoxia. Exogenous malate and α-KG exerted similar effect on HIF-1α in breast cancer cells to ME2 knockout or knockdown. Additionally,treatment with malate significantly decreased 4 T1 breast cancer lung metastasis. ME2 expression was associated with HIF-1α levels in human breast canc

关键词： Malic enzyme 2 breast cancer metastasis malate α-ketoglutarate hypoxia-inducible factor-1α

Solvent extraction with a three-dimensional reticulated hollow-strut SiC foam microchannel reactor

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Chinese Journal of Chemical Engineering 2022年第6期35卷 53-62页

作者： Ye Zhang Yong Gao Peng Wang duo Na Zhenming yang Jinsong Zhang School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Recently,there has been considerable interest in the use of microchannel reactors for hydrometallurgy of rare earths(REs).Here,a novel integrated microchannel reactor based on the hollow-strut SiC foam material is presented and demonstrated to extract Ce^(3+)and Pr^(3+)using 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester(P507)as the *** typical three-dimensional reticulated structure of the hollow-strut SiC foam was characterized by scanning electron microscopy and X-ray micro computed *** the reactor’s structure plays a key role in fluid mixing and mass diffusion during the extraction process,the structure-performance relationship of the foam was studied by extraction experiments combined with numerical *** the foam with the optimal structure,the influence of the flow rate Q_(0) of the two liquid phases on the extraction efficiency η and overall volume mass transfer coefficient KLa was *** both RE ions,with increasing Q_(0),η decreases while KLa *** the total flow rate of the two phases of 4 ml·min^(-1),the η values of Pr^(3+)and Ce^(3+)reached 98.7%and 97.0%,*** the total flow rate of 36 ml·min^(-1) which was much higher than that of many other microchannel reactors reported in the literatures,the η values of Pr^(3+)and Ce^(3+)still reached 92.2%and 86.9%,respectively,and the KLa values of Pr^(3+)and Ce^(3+)were 0.198 and 0.161 s^(-1),respectively,similar to the high values reported for other microchannel reactors studied in previous *** findings indicate that the hollow-strut SiC foam microchannel reactor is suitable for use in REs extraction.

关键词： Extraction Hollow Foam Microchannels Numerical simulation

Advanced strategies in the application of gelatin-based bioink for extrusion bioprinting

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Bio-Design and Manufacturing 2023年第5期6卷 586-608页

作者： Jirong yang Huimin He duo Li Qian Zhang Lizhi Xu Changshun Ruan Research Center for Human Tissue and Organs Degeneration Institute of Biomedicine and BiotechnologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Mechanical Engineering The University of Hong KongHong Kong SARChina University of Chinese Academy of Sciences Beijing 100049China

The signiﬁcance of bioink suitability for the extrusion bioprinting of tissue-like constructs cannot be ***,derived from the hydrolysis of collagen,not only can mimic the extracellular matrix to immensely support cell function,but also is suitable for extrusion under certain ***,gelatin has been recognized as a promising bioink for extrusion ***,the development of a gelatin-based bioink with satisfactory printability and bioactivity to fabricate complex tissue-like constructs with the desired physicochemical properties and biofunctions for a speciﬁc biomedical application is still in its ***,in this review,we aim to comprehensively summarize the state-of-the-art methods of gelatin-based bioink application for extrusion ***ﬁrstly outline the properties and requirements of gelatin-based bioinks for extrusion bioprinting,highlighting the strategies to overcome their main limitations in terms of printability,structural stability and cell ***,the challenges and prospects are further discussed regarding the development of ideal gelatin-based bioinks for extrusion bioprinting to create complex tissue-like constructs with preferable physicochemical properties and biofunctions.

关键词： Gelatin-based bioink Extrusion bioprinting Tissue-like construct

Solvent extraction of Ce(Ⅲ) and Pr(Ⅲ) with P507 using SiC foam as a static mixer

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Journal of Rare Earths 2022年第4期40卷 676-686,I0006页

Extraction reactor is a major research area of interest within the field of rare earths extraction and *** foam offers excellent material characteristics as well as three-dimensional(3-D) reticulated structure;however,very little research has been carried out on its application in extraction reactor so *** this work,a static mixer reactor based on SiC foam was designed and demonstrated to extract and separate Ce(Ⅲ) and Pr(Ⅲ) from nitric acid media by using 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester(P507) as *** structure-performance relationship between SiC foam and extraction performance was studied by experiment combined with computational fluid dynamics(CFD)*** experiment data are in good agreement with the simulation *** experiment by using a Kenics mixer was carried out,and SiC foam shows better extraction and mass transfer *** the optimal structural SiC foam(pore size D=2.3 mm,open porosity ε=85%,foam length L=80 mm),high extraction efficiency η(Pr(Ⅲ):94.6%,Ce(Ⅲ):88.5%) and separation factor β(2.27) between Ce(Ⅲ) and Pr(Ⅲ) is achieved at a high total throughput of 200 mL/***,overall volumetric mass transfer coefficient K_(L)a of Pr(Ⅲ) and Ce(Ⅲ) are 0.519 and 0.378 s^(−1) at the residence time τ of 3.6 s,respectively,which reach the high level of microchannel reactors and are better than conventional extractors and other static *** foam is found to be applicable as a static mixer for efficient and high-throughput extraction and separation of rare earths.

关键词： SiC foam Extraction Static mixer Simulation Rare earths