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Trimetallic MOFs derived NiFe_(2)O_(4)/MoNi_(4)-NC Schottky heterojunctions with abundant defects and dielectric-magnetic coupling for electromagnetic response 被引量:1
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作者 Ya Ning Xiao Jiang +2 位作者 jun huang Yanfeng Gao Xiaojun Zeng 《Journal of Materials Science & Technology》 2025年第10期1-13,共13页
There is limited research reported on the multiple loss mechanism of electromagnetic waves(EMW)and the development of interface models.Dielectric loss and magnetic loss,as the two primary attenuation mechanisms in EMW... There is limited research reported on the multiple loss mechanism of electromagnetic waves(EMW)and the development of interface models.Dielectric loss and magnetic loss,as the two primary attenuation mechanisms in EMW absorbers,still pose challenges,especially in elucidating the correlation between composition,morphology,interface,and performance.Here,we construct 3D hierarchical porous conducting network structures and Schottky heterojunctions(MoNi_(4)@NC-NiFe_(2)O_(4)@NC)with a high density of defects,using trimetallic NiMoFe-MOFs.Synergistic enhancement of the dielectric and magnetic losses is realized through manipulation of the defects,interfaces,phase engineering,and magnetic resonance.In particular,the even dispersion of magnetic MoNi_(4) and NiFe_(2)O_(4)nanoparticles(NPs)within the carbon matrix triggers the creation of multiple heterogeneous interfaces.These inseparable interfaces,along with oxygen vacancies,play a role in enhancing dielectric polarization,while the closely spaced interactions among magnetic units contribute to magnetic loss.After optimizing the interfacial structure,NiFe_(2)O_(4)/MoNi_(4)-NC exhibits remarkable EMW absorption properties.A reflection loss(RL)value of-67.91 dB can be achieved at an ultra-thin thickness of 1.95 mm,and the effective absorption bandwidth(EAB,RL≤-10 dB)is as high as 5.76 GHz.Furthermore,we conducted radar scattering cross-section(RCS)simulations using computer simulation technology(CST)software,which revealed that NiFe_(2)O_(4)/MoNi_(4)-NC exhibits an RCS reduction value of 39.1 dB m^(2).Hence,this work provides comprehensive guidance for the construction of Schottky heterojunctions for lightweight EMW absorbers from a mechanistic point of view. 展开更多
关键词 Trimetallic NiMoFe-MOFs Multiple loss mechanisms Heterogeneous interfaces Schottky heterojunctions Electromagnetic response
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丝光沸石负载自支撑氮掺杂多孔碳纳米纤维电容器及高效选择性去除硬度离子
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作者 黄鋆 聂鹏飞 +3 位作者 鲁勇朝 李佳洋 王怡文 刘建允 《物理化学学报》 北大核心 2025年第7期65-74,共10页
电容去离子(CDI)是一种具有广阔前景的电脱盐技术。通过引入成本低、无毒的电极材料,CDI在水体硬度离子的选择性去除方面呈现显著优势。丝光沸石(MOR)是天然的、环保型离子交换材料。本研究通过静电纺丝法,将MOR有效嵌入纳米纤维,随后... 电容去离子(CDI)是一种具有广阔前景的电脱盐技术。通过引入成本低、无毒的电极材料,CDI在水体硬度离子的选择性去除方面呈现显著优势。丝光沸石(MOR)是天然的、环保型离子交换材料。本研究通过静电纺丝法,将MOR有效嵌入纳米纤维,随后进行炭化处理得到丝光沸石负载氮掺杂碳纳米纤维(MOR@N-CNF)。研究证实了MOR在碳纳米纤维基体中均匀分布。MOR@N-CNF表现出增强的亲水性的高的比表面积。而且纤维柔性好、导电性高,作为自支撑电极在CaCl_(2)溶液中,呈现高的电化学比电容(162.7 F·g^(−1))。直接用于CDI阴极与活性炭(AC)阳极构成非对称CDI系统,进行选择性硬度离子吸附。MOR@N-CNF阴极对Mg^(2+)和Ca^(2+)的吸附容量分别为1501和1416μmol·g^(−1),且对这两种离子的选择性远高于Na^(+)(对Ca^(2+)的选择性系数为9.7,对Mg^(2+)的选择性系数为8.9)。经过40次循环测试后,该电极保留了78%的吸附能力,展现出优异的循环稳定性。本研究不仅为离子交换型复合电极材料的制备提供了新思路,也进一步凸显了CDI技术在硬水软化领域的潜力。 展开更多
关键词 自支撑 碳纤维 电容去离子 选择性吸附 硬度离子
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Understanding surface charge effects in electrocatalysis.Part 2:Hydrogen peroxide reactions at platinum 被引量:1
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作者 jun huang Victor Climent +1 位作者 Axel Groß Juan M.Feliu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第11期2837-2849,共13页
Electrocatalytic activity is influenced by the surface charge on the solid catalyst.Conventionally,our attention has been focused on how the surface charge shapes the electric potential and concentration of ionic reac... Electrocatalytic activity is influenced by the surface charge on the solid catalyst.Conventionally,our attention has been focused on how the surface charge shapes the electric potential and concentration of ionic reactant(s)in the local reaction zone.Taking H_(2)O_(2)redox reactions at Pt(111)as a model system,we reveal a peculiar surface charge effect using ab initio molecular dynamics simulations of electrified Pt(111)-water interfaces.In this scenario,the negative surface charge on Pt(111)repels the O-O bond of the reactant(H_(2)O_(2))farther away from the electrode surface.This leads to a higher activation barrier for breaking the O-O bond.Incorporating this microscopic mechanism into a microkinetic-double-layer model,we are able to semi-quantitatively interpret the pH-dependent activity of H_(2)O_(2)redox reactions at Pt(111),especially the anomalously suppressed activity of H_(2)O_(2)reduction with decreasing electrode potential.The relevance of the present surface charge effect is also examined in wider scenarios with different electrolyte cations,solution pHs,crystal facets of the catalyst,and model parameters.In contrast with previous mechanisms focusing on how surface charge influences the local reaction condition at a fixed reaction plane,the present work gives an example in which the location of the reaction plane is adjusted by the surface charge. 展开更多
关键词 ELECTROCATALYSIS Surface charge effect Hydrogen peroxide reaction Pt(111)-aqueous solution interface Microkinetic-double-layer model
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删除Loop区域表面不稳定氨基酸提高(R)-ω-转氨酶热稳定性 被引量:5
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作者 谢东芳 吕常江 +5 位作者 方卉 杨卫康 胡升 赵伟睿 黄俊 梅乐和 《生物工程学报》 CAS CSCD 北大核心 2017年第12期1923-1933,共11页
手性胺是一类具有重要价值的医药及精细化工中间体,如何实现手性胺类化合物的不对称合成是目前人们普遍关注的一个焦点问题。ω-转氨酶(ω-Transaminase,ω-TA)是一类能直接合成对映体手性胺的天然生物催化剂。相比于(S)-ω-TA,(R)-ω-T... 手性胺是一类具有重要价值的医药及精细化工中间体,如何实现手性胺类化合物的不对称合成是目前人们普遍关注的一个焦点问题。ω-转氨酶(ω-Transaminase,ω-TA)是一类能直接合成对映体手性胺的天然生物催化剂。相比于(S)-ω-TA,(R)-ω-TA的研究较少,但其需求量随着手性胺类药物的发展日趋增大。提高具有潜在应用价值的(R)-ω-TA的热稳定性,将有利于手性胺的制备。本文利用Py MOL软件和YASARA软件预测来源于土曲霉Aspergillus terreus的(R)-ω-TA中具有高温度因子(B-factor)的Loop区域,通过定点突变对Loop区域表面不稳定氨基酸逐步进行删除获得突变酶。结果表明,突变酶R131del和突变酶P132-E133del半失活温度分别为41.1℃和39.4℃,比野生酶提高了2.6℃和0.9℃;在40℃下的半衰期分别为15.0 min和10.0 min,为野生酶的2.2倍和1.5倍。此外,在400 K和10 ns的分子模拟条件下,突变酶R131del在Loop区域的均方根涨落(Root mean square fluctuation,RMSF)比野生型低,突变酶P132-E133del在Loop区域增加了4个氢键。本研究通过删除(R)-ω-转氨酶Loop区域表面不稳定氨基酸提高了该蛋白的热稳定性,同时也为其他酶热稳定性的理性设计提供了方法学指导。 展开更多
关键词 手性胺 ω-转氨酶 B-FACTOR Loop区域 均方根涨落 热稳定性
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Optimal amino acid system for early embryo development in sows based on response surface methodology and high-throughput screening cell models
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作者 Xinyu Wang jun huang +12 位作者 Yanlong Li Zhekun Zhu Bangxin Xue Yueyang Meng Jiale Bao Ran Ning Siyu Li Fang Chen Shihai Zhang Xiangzhou Zeng Shuang Cai Chuanjiang Cai Xiangfang Zeng 《Journal of Animal Science and Biotechnology》 2025年第3期1324-1340,共17页
Background Early embryo development plays a pivotal role in determining pregnancy outcomes,postnatal development,and lifelong health.Therefore,the strategic selection of functional nutrients to enhance embryo developm... Background Early embryo development plays a pivotal role in determining pregnancy outcomes,postnatal development,and lifelong health.Therefore,the strategic selection of functional nutrients to enhance embryo development is of paramount importance.In this study,we established a stable porcine trophectoderm cell line expressing dual fluorescent reporter genes driven by the CDX2 and TEAD4 gene promoter segments using lentiviral transfection.Results Three amino acid metabolites—kynurenic acid,taurine,and tryptamine—met the minimum z-score criteria of 2.0 for both luciferase and Renilla luciferase activities and were initially identified as potential metabolites for embryo development,with their beneficial effects validated by qPCR.Given that the identified metabolites are closely related to methionine,arginine,and tryptophan,we selected these three amino acids,using lysine as a standard,and employed response surface methodology combined with our high-throughput screening cell model to efficiently screen and optimize amino acid combination conducive to early embryo development.The optimized candidate amino acid system included lysine(1.87 mmol/L),methionine(0.82 mmol/L),tryptophan(0.23 mmol/L),and arginine(3 mmol/L),with the ratio of 1:0.43:0.12:1.60.In vitro experiments confirmed that this amino acid system enhances the expression of key genes involved in early embryonic development and improves in vitro embryo adhesion.Transcriptomic analysis of blastocysts suggested that candidate amino acid system enhances early embryo development by regulating early embryonic cell cycle and differentiation,as well as improving nutrient absorption.Furthermore,based on response surface methodology,400 sows were used to verify this amino acid system,substituting arginine with the more cost-effective N-carbamoyl glutamate(NCG),a precursor of arginine.The optimal dietary amino acid requirement was predicted to be 0.71%lysine,0.32%methionine,0.22%tryptophan,and 0.10%NCG for sows during early gestation.The optimized amino acid system ratio of the feed,derived from the peripheral release of essential amino acids,was found to be 1:0.45:0.13,which is largely consistent with the results obtained from the cell model optimization.Subsequently,we furtherly verified that this optimal dietary amino acid system significantly increased total litter size,live litter size and litter weight in sows.Conclusions In summary,we successfully established a dual-fluorescent high-throughput screening cell model for the efficient identification of potential nutrients that would promote embryo development and implantation.This innovative approach overcomes the limitations of traditional amino acid nutrition studies in sows,providing a more effective model for enhancing reproductive outcomes. 展开更多
关键词 Amino acid Embryonic development High throughput screening NUTRIENT Response Surface Methodology
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Poly(Norbornene-Diphenothiazine)for Electrochemical Capture and Release of Chromium and Arsenic Oxyanions from Water
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作者 Chen Li Dandong Wang +6 位作者 Zhengyang Zhang Jae Uk Choi jun huang Ki-Taek Bang Shaopeng Xu Yanming Wang Yoonseob Kim 《Energy & Environmental Materials》 2025年第3期253-263,共11页
Drinking water contamination by heavy metals,particularly chromium and arsenic oxyanions,is a severe challenge threatening humanity’s sustainable development.Electrochemically mediated water purification is gaining a... Drinking water contamination by heavy metals,particularly chromium and arsenic oxyanions,is a severe challenge threatening humanity’s sustainable development.Electrochemically mediated water purification is gaining attention due to its high uptake,rapid kinetics,modularity,and facile regeneration.Here,we designed a composite electrode by combining a redox-active/Faradaic polymer,poly(norbornene-diphenothiazine)(PNP_(2)),with carbon nanotubes(CNTs)–PNP_(2)-CNT.The PNP_(2)-CNT demonstrated exceptional pseudocapacitance behavior,resulting in significantly accelerated adsorption rates for dichromate(Cr(Ⅵ);0.008 gmg^(-1) min^(-1))and arsenite(As(Ⅲ);0.03 gmg^(-1) min^(-1)),surpassing reported materials by a margin of 3–200 times,while demonstrating a high adsorption capacity,666.3 and 612.4 mg g^(-1),respectively.Furthermore,it effectively converted As(Ⅲ)to the less toxic arsenate(As(Ⅴ))during adsorption and Cr(Ⅵ)to the less toxic chromium(Cr(Ⅲ))during desorption.This PNP_(2)-CNT system also showed significantly lower energy consumption,only 0.17%of the CNT control system.This study demonstrated for the first time the use of PNP_(2) redox-active polymers in the separation and conversion process,meeting the six criteria of high uptake,rapid kinetics,selectivity,stability,recyclability,and energy efficiency.This achievement expands the scope of advanced materials that address environmental concerns and make an impact by generating energy-and cost-effective water purification. 展开更多
关键词 adsorption conversion faradaic polymer PSEUDOCAPACITANCE redox-active polymer
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Proline‑driven metabolic reprogramming promotes skeletal muscle hypertrophy and oxidative myofiber specification in porcine offspring:a stage‑optimized maternal nutritional intervention
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作者 jun huang Kaidi Ma +6 位作者 junyi Wu Shuangbo huang Zihao huang Yujiao Chen Shijian Zhou Hefeng Luo Chengquan Tan 《Journal of Animal Science and Biotechnology》 2025年第5期2446-2457,共12页
Background While maternal proline(Pro)supplementation has demonstrated efficacy in enhancing placental angiogenesis and farrowing efficiency in swine,its regulatory role in fetal skeletal muscle ontogeny remains undef... Background While maternal proline(Pro)supplementation has demonstrated efficacy in enhancing placental angiogenesis and farrowing efficiency in swine,its regulatory role in fetal skeletal muscle ontogeny remains undefined.This study systematically evaluated the temporal-specific impacts of dietary Pro supplementation during critical phases of fetal myogenesis(encompassing primary myofiber formation and secondary myofiber hyperplasia)on offspring muscle development.A total of 120 sows with similar farrowing schedules were assigned to three groups:CON(basal diet),ST-Pro(0.5%Pro supplementation during secondary myofiber formation period,from d 60 gestation to farrowing),LT-Pro(0.5%Pro supplementation spanning primary and secondary myofiber formation period:from d 20 gestation to farrowing).Results LT-Pro group significantly increased the longissimus dorsi(LD)muscle mass per unit body weight in newborn piglets compared to CON group(P<0.05),while no such effect was observed in the ST-Pro group.Metabolomic profiling revealed elevated Pro,lysine,and tryptophan levels in the LD muscle of LT-Pro group piglets,accompanied by reduced branched-chain amino acids(BCAAs;leucine,isoleucine,and valine)in both serum and muscle(P<0.05).Histological analysis demonstrated a 45.74%increase in myofiber cross-sectional area in the LT-Pro group(P<0.05).At the molecular level,LT-Pro group piglets exhibited upregulated mRNA expression levels of myogenic regulatory genes(MYOD1,MYF6)and the cell cycle accelerator CCND1(P<0.05),coupled with activation of the STAT3 signaling pathway(phosphorylated STAT3 protein increased by 2.53-fold,P<0.01).Furthermore,Pro supplementation enhanced oxidative metabolism,evidenced by elevated mitochondrial biogenesis markers(the mRNA expression levels of PPARGC1A,OPA1,and SQSTM1)and a 61.58%increase in succinate dehydrogenase activity(P<0.05).Notably,LT-Pro group piglets showed a selective shift toward slow-twitch oxidative fibers,with both MyHC1 mRNA and protein expression levels significantly upregulated(P<0.05),while the mRNA expression levels of MyHCIIb showed no significant change.Conclusions This study identified the primary fiber formation period as a critical window.Supplementation with Pro during G20–114 reprogrammed offspring skeletal muscle development through STAT3-CCND1-mediated myoblast proliferation,enhanced mitochondrial bioenergetics,and oxidative fiber specification.However,no such effects were observed during G60–114.These findings propose maternal Pro intervention as a novel strategy to enhance muscle yield and metabolic efficiency in swine production,with potential applications for improving meat quality traits linked to oxidative muscle phenotypes. 展开更多
关键词 Mitochondrial function Oxidative muscle fibers PROLINE Skeletal muscle development STAT3 signaling pathway
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A semiconductor radiation dosimeter fabricated in 8-inch process
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作者 jun huang Bojin Pan +10 位作者 Hang bao Qiuyue Huo Renxiong Li Qi Ding Yutuo Guo Yu Wang Kunqin He Yaxin Liu Ziyi Zeng Ning Ning Lulu Peng 《Journal of Semiconductors》 2025年第8期54-58,共5页
The radiation-sensitive field effect transistors(RADFET)radiation dosimeter is a type of radiation detector based on the total dose effects of the p-channel metal-oxide-semiconductor(PMOS)transistor.The RADFET chip wa... The radiation-sensitive field effect transistors(RADFET)radiation dosimeter is a type of radiation detector based on the total dose effects of the p-channel metal-oxide-semiconductor(PMOS)transistor.The RADFET chip was fabricated in United Microelectronics Center 8-inch process with a six-layer photomask.The chip including two identical PMOS transistors,occupies a size of 610μm×610μm.Each PMOS has a W/L ratio of 300μm/50μm,and a 400 nm thick gate oxide,which is formed by a dry-wet-dry oxygen process.The wet oxygen-formed gate oxide with more traps can capture more holes during irradiation,thus significantly changing the PMOS threshold voltage.Pre-irradiation measurement results from ten test chips show that the initial average voltage of the PMOS is 1.961 V with a dispersion of 5.7%.The irradiation experiment is conducted in a cobalt source facility with a dose rate of 50 rad(Si)/s.During irradiation,a constant current source circuit of 10μA was connected to monitoring the shift in threshold voltage under different total dose.When the total dose is 100 krad(Si),the shift in threshold voltage was approximately 1.37 V,which demonstrates that an excellent radiation function was achieved. 展开更多
关键词 RADFET PMOS thick gate oxide total dose effect radiation detection
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面向网络空间安全专业的汇编语言课程“多维一体”教学改革
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作者 张云峰 黄郡 +2 位作者 张敬业 卢灿举 牛钊 《计算机教育》 2025年第10期108-113,共6页
为了提升网络空间安全专业汇编语言课程教学质量,在分析课程教学现状的基础上,提出优化课程设计、在教学中应用逆向分析、网络安全案例贯穿教学全过程、引导学生在学习中正确运用人工智能、实验教学覆盖全程、发挥教学平台优势等方法,... 为了提升网络空间安全专业汇编语言课程教学质量,在分析课程教学现状的基础上,提出优化课程设计、在教学中应用逆向分析、网络安全案例贯穿教学全过程、引导学生在学习中正确运用人工智能、实验教学覆盖全程、发挥教学平台优势等方法,经过实践说明该方法能够提高教学质量。 展开更多
关键词 网络空间安全 汇编语言 教学改革
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Bioinformatics Analysis of the Association between Ewing’s Sarcoma and Tuberculosis Comorbidity
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作者 jun huang Qi Lu +3 位作者 junxiu Zhou Wenzhao Zhang Chongyao Xu Guiyun Wei 《Journal of Biosciences and Medicines》 2024年第8期128-140,共13页
Objective To screen and analyze the differentially expressed genes of Ewing’s sarcoma (ES) and Tuberculosis (TB) by bioinformatics. Methods GEO gene chip public database in NCBI was used for data retrieval, and chip ... Objective To screen and analyze the differentially expressed genes of Ewing’s sarcoma (ES) and Tuberculosis (TB) by bioinformatics. Methods GEO gene chip public database in NCBI was used for data retrieval, and chip data GSE17674 and GSE57736 were selected as analysis objects. The R language limma toolkit was used to screen DEmRNAs, and the data were standardized, and the common differentially expressed genes were screened by Venn diagram. The GO function and KEGG pathway enrichment of common differentially expressed genes were analyzed by using the R cluster Profiler package. String database was selected for PPI analysis, and the results were imported into Cytoscape software to obtain PPI interaction map, core module and Hub gene. Import Hub gene into BioGPS database. Results: A total of 3 Hub genes were screened, namely CD3D, LCK, KLRB1;The genes were imported into BioGPS database to obtain the specific genes. Conclusion The selected differential genes and related signaling pathways are helpful to understand the molecular mechanism of ES and TB, and can provide the basis for early diagnosis of ES complicated with TB. It also provides new ideas for clinical treatment and diagnosis. 展开更多
关键词 ES NFH Bioinformatics Analysis Differential Gene Signal Path
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Bioinformatics Analysis of the Relationship between Dilated Cardiomyopathy and Chronic Heart Failure
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作者 Lanqing Yu Haidong Zhou +8 位作者 Bailu Deng Jiaochang Wei Mei Zhang Chongyao Xu Guiyun Wei junxiu Zhou jun huang Qi Lu Shaowu Ye 《Journal of Biosciences and Medicines》 2024年第8期333-346,共14页
Objective: To screen and analyze the differentially expressed genes between dilated cardiomyopathy (DCM) and chronic heart failure (CHF) based on bioinformatics methods. Methods: The Gene Expression Omnibus (GEO) data... Objective: To screen and analyze the differentially expressed genes between dilated cardiomyopathy (DCM) and chronic heart failure (CHF) based on bioinformatics methods. Methods: The Gene Expression Omnibus (GEO) database was used for data retrieval, and the chip data GSE3585 was downloaded, which was the original data of DCM and normal control group. At the same time, the chip data GSE76701 was downloaded, which was the original data of CHF and control group. Differentially expressed mRNAs (DEmRNAs) were screened by R language limma package, the data were standardized, and the common differentially expressed genes were screened. GO function and KEGG pathway enrichment analysis were performed on the common differentially expressed genes. String11.0 online tool was used for data analysis to obtain differentially expressed genes, and the results were imported into Cytoscape 3.9.1 software. The results were imported into Cytoscape 3.9.1 software, and the common expression gene module was obtained by MOCDE algorithm. Nine Hub genes were obtained by 10 algorithms such as MCC. Results: A total of 248 differentially expressed genes were screened. GO analysis showed that differentially expressed genes were mainly concentrated in 9 different physiological and pathological processes. KEGG analysis showed that the main signaling pathways involved in differentially expressed genes were 2, and 9 key differentially expressed genes were predicted: NPPB, NPPA, MYH6, FRZB, ASPN, SFRP4, RPS4Y1, DDX3Y. Conclusion: This study preliminarily explored the molecular mechanism of DCM and CHF, and obtained the common differentially expressed genes of the two diseases. Further experimental studies are needed to verify the correlation between gene expression and clinicopathological features. Provide new ideas for clinical drug treatment research. 展开更多
关键词 Dilated Cardiomyopathy Chronic Heart Failure Bioinformatics Analysis Differentially Expressed Genes
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利用脯氨酸效应提高短乳杆菌谷氨酸脱羧酶的热稳定性 被引量:4
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作者 方卉 吕常江 +6 位作者 花雨娇 胡升 赵伟睿 方文姬 宋奎 黄俊 梅乐和 《生物工程学报》 CAS CSCD 北大核心 2019年第4期636-646,共11页
以磷酸吡哆醛为辅酶的谷氨酸脱羧酶(Glutamate decarboxylase,GAD),能专一、不可逆地催化L-谷氨酸脱去α-羧基生成γ-氨基丁酸。为了提高GAD热稳定性为目标,本研究通过与嗜热古细菌Thermococcus kodakarensis中GAD氨基酸序列的比对及引... 以磷酸吡哆醛为辅酶的谷氨酸脱羧酶(Glutamate decarboxylase,GAD),能专一、不可逆地催化L-谷氨酸脱去α-羧基生成γ-氨基丁酸。为了提高GAD热稳定性为目标,本研究通过与嗜热古细菌Thermococcus kodakarensis中GAD氨基酸序列的比对及引入脯氨酸策略,最终在短乳杆菌Lactobacillus brevis CGMCC No.1306的GAD突变体中筛选得到热稳定性提高的突变酶G364P。结果显示,突变酶G364P在55℃的半衰期以及半失活温度分别比野生酶提高19.4 min和5.3℃,并且突变酶G364P的催化效率与野生酶相比没有明显变化。此外,利用分子动力学模拟来验证突变对蛋白质热稳定性的影响,突变酶G364P的均方根偏差(Rootmeansquare deviation,RMSD)以及含G364的loop区域均方根涨落(Root mean square fluctuation,RMSF)均比野生酶低,引入脯氨酸增加了364位氨基酸与相邻氨基酸的疏水相互作用。文中通过引入脯氨酸成功提高了L. brevis中GAD的热稳定性,同时也为其他酶热稳定性的理性设计提供了方法学指导。 展开更多
关键词 谷氨酸脱羧酶 脯氨酸 Γ-氨基丁酸 短乳杆菌 热稳定性 分子动力学
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适应创新性人才培养的仪器分析实验教学改革初探 被引量:14
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作者 黄军 周颖琳 +2 位作者 吕占霞 高珍 李美仙 《大学化学》 CAS 2022年第4期70-74,共5页
为适应创新性人才培养,本文介绍了北京大学化学与分子工程学院仪器分析实验教学团队所进行的教学改革初步探索,包括采用线上线下相结合的学习模式;增加实际样品测试;采取小班教学模式;对同一样品采用多种分析方法进行对比测试等。这些... 为适应创新性人才培养,本文介绍了北京大学化学与分子工程学院仪器分析实验教学团队所进行的教学改革初步探索,包括采用线上线下相结合的学习模式;增加实际样品测试;采取小班教学模式;对同一样品采用多种分析方法进行对比测试等。这些改革措施的实施,显著提高了课程质量和教学效果。 展开更多
关键词 仪器分析实验 教学 改革 探索
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SwinFusion: Cross-domain Long-range Learning for General Image Fusion via Swin Transformer 被引量:67
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作者 Jiayi Ma Linfeng Tang +3 位作者 Fan Fan jun huang Xiaoguang Mei Yong Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第7期1200-1217,共18页
This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achi... This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achieve sufficient integration of complementary information and global interaction.More specifically,the proposed method involves an intra-domain fusion unit based on self-attention and an interdomain fusion unit based on cross-attention,which mine and integrate long dependencies within the same domain and across domains.Through long-range dependency modeling,the network is able to fully implement domain-specific information extraction and cross-domain complementary information integration as well as maintaining the appropriate apparent intensity from a global perspective.In particular,we introduce the shifted windows mechanism into the self-attention and cross-attention,which allows our model to receive images with arbitrary sizes.On the other hand,the multi-scene image fusion problems are generalized to a unified framework with structure maintenance,detail preservation,and proper intensity control.Moreover,an elaborate loss function,consisting of SSIM loss,texture loss,and intensity loss,drives the network to preserve abundant texture details and structural information,as well as presenting optimal apparent intensity.Extensive experiments on both multi-modal image fusion and digital photography image fusion demonstrate the superiority of our SwinFusion compared to the state-of-theart unified image fusion algorithms and task-specific alternatives.Implementation code and pre-trained weights can be accessed at https://github.com/Linfeng-Tang/SwinFusion. 展开更多
关键词 Cross-domain long-range learning image fusion Swin transformer
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烧结NdFeB磁体表面Zn-Al/T8超疏水复合涂层的显微组织及耐蚀性
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作者 张晓虎 罗军明 +4 位作者 徐吉林 陈金 黄俊 马永存 薛名山 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第5期1606-1617,共12页
为提升烧结NdFeB磁体的耐蚀性,采用旋涂法和等离子体增强化学气相沉积技术在其表面制备Zn-Al/T8(2-全氟辛基乙基丙烯酸酯)超疏水复合涂层。结果表明,Zn-Al涂层主要由片层状的Zn和Al相组成,厚度大约为28μm。Zn-Al/T8复合涂层的接触角达... 为提升烧结NdFeB磁体的耐蚀性,采用旋涂法和等离子体增强化学气相沉积技术在其表面制备Zn-Al/T8(2-全氟辛基乙基丙烯酸酯)超疏水复合涂层。结果表明,Zn-Al涂层主要由片层状的Zn和Al相组成,厚度大约为28μm。Zn-Al/T8复合涂层的接触角达到151.78°,而滚动角仅为5.13°,说明Zn-Al/T8复合涂层可提供一个超疏水表面。Zn-Al涂层和Zn-Al/T8复合涂层对烧结NdFeB的磁性能均无显著影响。Zn-Al涂层通过牺牲阳极来提高NdFeB磁体的耐蚀性,而Zn-Al/T8复合涂层通过超疏水表面进一步提升耐蚀性。Zn-Al/T8复合涂层较Zn-Al涂层具有更好的耐盐雾性能。Zn-Al/T8超疏水复合涂层是一种非常有前途的烧结NdFeB磁体保护涂层。 展开更多
关键词 显微组织 耐蚀性 烧结NDFEB磁体 Zn-Al涂层 超疏水表面 旋涂法 等离子体增强化学气相沉积
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Risk factors for sporadic colorectal cancer in southern Chinese 被引量:11
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作者 Yi-Sheng Wei Jia-Chun Lu +5 位作者 Lei Wang Ping Lan Hong-jun Zhao Zhi-Zhong Pan jun huang Jian-Ping Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第20期2526-2530,共5页
AIM:To investigate the role of smoking, alcohol drinking, family history of cancer, and body mass index(BMI) in sporadic colorectal cancer in southern Chinese.METHODS:A hospital-based case-control study was conducted ... AIM:To investigate the role of smoking, alcohol drinking, family history of cancer, and body mass index(BMI) in sporadic colorectal cancer in southern Chinese.METHODS:A hospital-based case-control study was conducted from July 2002 to December 2008.There were 706 cases and 723 controls with their sex and age(within 5 years) matched.An unconditional logistic regression model was used to analyze the association between smoking, alcohol drinking, family history of cancer, BMI and sporadic colorectal cancer.RESULTS:No positive association was observed between smoking status and sporadic colorectal cancer risk.Compared with the non alcohol drinkers, the current and former alcohol drinkers had an increased risk of developing sporadic colorectal cancer(CRC)(adjusted OR = 8.61 and 95% CI = 6.15-12.05;adjusted OR = 2.30, 95% CI = 1.27-4.17).Moreover, the increased risk of developing sporadic CRC was significant in those with a positive family history of cancer(adjusted OR = 1.62, 95% CI = 1.12-3.34) and in those with their BMI ≥ 24.0 kg/m2(adjusted OR = 1.39, 95% CI = 1.10-1.75).Stratification analysis showed that the risk of developing both colon and rectal cancers was increased in current alcohol drinkers(adjusted OR = 7.60 and 95% CI = 5.13-11.25;adjusted OR = 7.52 and 95% CI = 5.13-11.01) and in those with their BMI ≥ 24.0 kg/m2(adjusted OR = 1.38 and 95% CI = 1.04-1.83;adjusted OR = 1.35 and 95% CI = 1.02-1.79).The risk of developing colon cancer, but not rectal cancer, was found in former alcohol drinkers and in those with a positive family history of cancer(adjusted OR = 2.51 and 95% CI = 1.24-5.07;adjusted OR = 1.82 and 95% CI = 1.17-2.82).CONCLUSION:Alcohol drinking, high BMI(≥ 24.0 kg/m2) and positive family history of cancer are the independent risk factors for colorectal cancer in southern Chinese. 展开更多
关键词 CASE-CONTROL Colorectal cancer Risk factors SMOKING Alcohol drinking Body mass index Family history
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Emerging Organic Contaminants in Chinese Surface Water:Identification of Priority Pollutants 被引量:17
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作者 Mengmeng Zhong Tielong Wang +5 位作者 Wenxing Zhao jun huang Bin Wang Lee Blaney Qingwei Bu Gang Yu 《Engineering》 SCIE EI 2022年第4期111-125,共15页
The occurrence and impacts of emerging organic contaminants(EOCs)in the aquatic environment have gained widespread attention over the past two decades.Due to large number of potential contaminants,monitoring campaigns... The occurrence and impacts of emerging organic contaminants(EOCs)in the aquatic environment have gained widespread attention over the past two decades.Due to large number of potential contaminants,monitoring campaigns,treatment plants,and proposed regulations should preferentially focus on specific pollutants with the highest potential for ecological and human health effects.In the present study,a multi-criteria screening approach based on hazard and exposure potentials was developed for prioritization of 405 unregulated EOCs already present in Chinese surface water.Hazard potential,exposure potential,and risk quotients for ecological and human health effects were quantitatively analyzed and used to screen contaminants.The hazard potential was defined by contaminant persistence,bioaccumulation,ecotoxicity,and human health effects;similarly,the exposure potential was a function of contaminant concentration and detection frequency.In total,123 compounds passed the preselection process,which involved a priority index equal to the normalized hazard potential multiplied by the normalized exposure potential.Based on the prioritization scheme,11 compounds were identified as top-priority,and 37 chemicals were defined as high-priority.The results obtained by the priority index were compared with four other prioritization schemes based on exposure potential,hazard potential,or risk quotients for ecological effects or human health.The priority index effectively captured and integrated the results from the more simplistic prioritization schemes.Based on identified data gaps,four uncertainty categories were classified to recommend:①regular monitoring,derivation of environmental quality standards,and development of control strategies;②increased monitoring;③fortified hazard assessment;and④increased efforts to collect occurrence and toxicity data.Overall,20 pollutants were recommended as priority EOCs.The prioritized list of contaminants provides the necessary information for authoritative regulations to monitor,control,evaluate,and manage the risks of environmentally-relevant EOCs in Chinese surface water. 展开更多
关键词 PRIORITIZATION Emerging organic contaminants Hazard potential ECOTOXICITY Risk assessment
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SuperFusion: A Versatile Image Registration and Fusion Network with Semantic Awareness 被引量:13
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作者 Linfeng Tang Yuxin Deng +2 位作者 Yong Ma jun huang Jiayi Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第12期2121-2137,共17页
Image fusion aims to integrate complementary information in source images to synthesize a fused image comprehensively characterizing the imaging scene. However, existing image fusion algorithms are only applicable to ... Image fusion aims to integrate complementary information in source images to synthesize a fused image comprehensively characterizing the imaging scene. However, existing image fusion algorithms are only applicable to strictly aligned source images and cause severe artifacts in the fusion results when input images have slight shifts or deformations. In addition,the fusion results typically only have good visual effect, but neglect the semantic requirements of high-level vision tasks.This study incorporates image registration, image fusion, and semantic requirements of high-level vision tasks into a single framework and proposes a novel image registration and fusion method, named Super Fusion. Specifically, we design a registration network to estimate bidirectional deformation fields to rectify geometric distortions of input images under the supervision of both photometric and end-point constraints. The registration and fusion are combined in a symmetric scheme, in which while mutual promotion can be achieved by optimizing the naive fusion loss, it is further enhanced by the mono-modal consistent constraint on symmetric fusion outputs. In addition, the image fusion network is equipped with the global spatial attention mechanism to achieve adaptive feature integration. Moreover, the semantic constraint based on the pre-trained segmentation model and Lovasz-Softmax loss is deployed to guide the fusion network to focus more on the semantic requirements of high-level vision tasks. Extensive experiments on image registration, image fusion,and semantic segmentation tasks demonstrate the superiority of our Super Fusion compared to the state-of-the-art alternatives.The source code and pre-trained model are publicly available at https://github.com/Linfeng-Tang/Super Fusion. 展开更多
关键词 Global spatial attention image fusion image registration mutual promotion semantic awareness
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Rapid removal of bisphenol A on highly ordered mesoporous carbon 被引量:10
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作者 Qian Sui jun huang +5 位作者 Yousong Liu Xiaofeng Chang Guangbin Ji Shubo Deng Tao Xie Gang Yu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第2期177-182,共6页
Bisphenol A (BPA) is of global concern due to its disruption of endocrine systems and ubiquity in the aquatic environment. It is important, therefore, that efforts are made to remove it from the aqueous phase. A nov... Bisphenol A (BPA) is of global concern due to its disruption of endocrine systems and ubiquity in the aquatic environment. It is important, therefore, that efforts are made to remove it from the aqueous phase. A novel adsorbent, mesoporous carbon CMK-3, prepared from hexagonal SBA- 15 mesoporous silica was studied for BPA removal from aqueous phase, and compared with conventional powdered activated carbon (PAC). Characterization of CMK-3 by transmission electron microscopy (TEM), X-ray diffraction, and nitrogen adsorption indicated that prepared CMK-3 had an ordered mesoporous structure with a high specific surface area of 920 m^2/g and a pore-size of about 4.9 nm. The adsorption of BPA on CMK-3 followed a pseudo second-order kinetic model. The kinetic constant was 0.00049 g/(mg.min), much higher than the adsorption of BPA on PAC. The adsorption isotherm fitted slightly better with the Freundlich model than the Langmuir model, and adsorption capacity decreased as temperature increased from 10 to 40℃. No significant influence of pH on adsorption was observed at pH 3 to 9; however, adsorption capacity decreased dramatically from pH 9 to 13. 展开更多
关键词 mesoporous carbon CMK-3 powdered activated carbon bisphenol A endocrine disrupting chemicals
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Advances in Valveless Piezoelectric Pump with Cone-shaped Tubes 被引量:12
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作者 Jian-Hui Zhang Ying Wang jun huang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期766-781,共16页
This paper reviews the development of valve- less piezoelectric pump with cone-shaped tube chrono- logically, which have widely potential application in biomedicine and micro-electro-mechanical systems because of its ... This paper reviews the development of valve- less piezoelectric pump with cone-shaped tube chrono- logically, which have widely potential application in biomedicine and micro-electro-mechanical systems because of its novel principles and deduces the research direction in the future. Firstly, the history of valveless piezoelectric pumps with cone-shaped tubes is reviewed and these pumps are classified into the following types: single pump with solid structure or plane structure, and combined pump with parallel structure or series structure. Furthermore, the function of each type of cone-shaped tubes and pump structures are analyzed, and new direc- tions of potential expansion of valveless piezoelectric pumps with cone-shaped tubes are summarized and deduced. The historical argument, which is provided by the literatures, that for a valveless piezoelectric pump with cone-shaped tubes, cone angle determines the flow resistance and the flow resistance determines the flow direction. The argument is discussed in the reviewed pumps one by one, and proved to be convincing. Finally, it is deduced that bionics is pivotal in the development of valveless piezoelectric pump with cone-shaped tubes fromthe perspective of evolution of biological structure. This paper summarizes the current valveless piezoelectric pumps with cone-shaped tubes and points out the future development, which may provide guidance for the research of piezoelectric actuators. 展开更多
关键词 Piezoelectric pump Valveless Cone-shapedtube BIONICS
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