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Synthetic and Systems Biotechnology 2024年第3期9卷 503-512页

作者： Bing Fu Meng Chen Xianfeng bao Jiajie Lu Zhiwen zhu Fuyao Guan Chuyang Yan Peize Wang Linglin Fu Ping Yu College of Food Science and Biotechnology Zhejiang Gongshang University149 Jiaogong RoadHangzhouZhejiang Province310035People’s Republic of China College of Forestry Science and Technology Lishui Vocational and Technical College357 Zhongshan Street NorthLishuiZhejiang Province323000People’s Republic of China Lishui Institute for Quality Inspection and Testing 395 Zhongshan StreetLishuiZhejiang Province323000People’s Republic of China

Vitamin B_(2)is an essential water-soluble *** most prokaryotes,a bifunctional enzyme called FAD synthase catalyzes the successive conversion of riboflavin to FMN and *** this study,the plasmid pNEW-AZ containing six key genes for the riboflavin synthesis was transformed into strain R2 with the deleted FMN riboswitch,yielding strain *** R5 strain could produce 540.23±5.40 mg/L riboflavin,which was 10.61%higher than the R4 strain containing plasmids pET-AE and pAC-Z harboring six key *** further enhance the production of riboflavin,homology matching and molecular docking were performed to identify key amino acid residues of FAD *** point mutation sites were *** comparing riboflavin kinase activity,mutations of T203D and N210D,which respectively decreased by 29.90%and 89.32%compared to wild-type FAD synthase,were selected for CRISPR/Cas9 gene editing of the genome,generating engineered strains R203 and ***-AZ was transformed into R203,generating R6.R6 produced 657.38±47.48 mg/L riboflavin,a 21.69%increase compared to *** study contributes to the high production of riboflavin in recombinant *** BL21.

关键词： Vitamin B_(2) FAD synthase Escherichia coli BL21 Riboflavin kinase CRISPR/Cas9

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不同荷电性聚氯乙烯超滤膜制备及性能

高校化学工程学报 2020年第6期34卷 1527-1535页

作者：谢艳新唐玉岭杨倩周名勇朱宝库新乡学院化学与材料工程学院河南新乡453003 浙江大学高分子科学与工程学系浙江杭州310027

为提高聚氯乙烯(PVC)的亲水性和抗污染性能,分别将聚乙二醇(PEG 20000)、聚(氯乙烯-co-甲基丙烯酸二甲氨基乙酯)(PVD)和磺化聚砜(SPSf)引入PVC基质中,非溶剂致相转化法(NIPS)制备出电中性PVC/PEG(M1)、荷正电PVC/PVD(M2)和荷负电PVC/SPS... 详细信息

为提高聚氯乙烯(PVC)的亲水性和抗污染性能,分别将聚乙二醇(PEG 20000)、聚(氯乙烯-co-甲基丙烯酸二甲氨基乙酯)(PVD)和磺化聚砜(SPSf)引入PVC基质中,非溶剂致相转化法(NIPS)制备出电中性PVC/PEG(M1)、荷正电PVC/PVD(M2)和荷负电PVC/SPSf(M3)3种共混超滤膜。并研究3种膜的表面化学组成、结构形貌、孔径和孔隙率、水接触角、荷电性、渗透性、牛血清蛋白(BSA)截留及抗污染性能。结果表明:M1、M2和M3均是具有海绵结构的超滤膜,孔隙率、水接触角和纯水通量均表现为M1>M3>M2。对BSA的截留率为M3(99.3%)>M2(90.6%)>M1(86.2%),通量恢复率为M3(98.2%)>M1(90.1%)>M2(73.0%),荷负电的M3具有更优异的持久抗污染能力。

关键词：荷电膜聚氯乙烯聚(氯乙烯-co-甲基丙烯酸二甲氨基乙酯) 磺化聚砜超滤

A sustainable process to 100%bio-based nylons integrated chemical and biological conversion of lignocellulose

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Green Energy & Environment 2024年第2期9卷 390-402页

作者： Ruijia Hu Ming Li Tao Shen Xin Wang zhuohua Sun Xinning bao Kequan Chen Kai Guo Lei Ji Hanjie Ying Pingkai Ouyang Chenjie zhu College of Biotechnology and Pharmaceutical Engineering Nanjing Tech UniversityNanjingChina National Engineering Research Center for Biotechnology Nanjing Tech UniversityNanjingChina Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijingChina

Considerable progress has been made in recent years to the development of sustainable polymers from bio-based *** this study,100%bio-based nylons were prepared via an integrated chemical and biological process from *** novel nylons were obtained by the melt polymerization of 3-propyladipic acid derived from lignin and 1,5-pentenediamine/1,4-butanediamine derived from carbohydrate *** to the concept is a three-step noble metal free catalytic chemical funnelling sequence(Raney Ni mediated reductive catalytic fractionation-reductive funnelling-oxidative funnelling),which allowed for obtaining a single component 3-propyladipic acid from lignin with high *** structural and thermodynamic properties of the obtained nylons have been systematically investigated,and thus obtained transparent bio-based nylons exhibited higher Mw(>32,000)and excellent thermal stability(Td5%>265℃).Considering their moderate Tg and good melt strength,these transparent bio-based nylons could serve as promising functional additives or temperature-responsive materials.

关键词： Lignocellulose Lignin Reductive catalytic fractionation Bio-based nylon

含PVDF-HFP多孔骨架和交联PEG的锂离子凝胶膜制备与性能

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功能材料 2007年第2期38卷 234-237,242页

作者：崔振宇朱宝库韩改格徐又一浙江大学高分子科学研究所教育部高分子合成与功能构造重点实验室浙江杭州310027

锂离子导电膜是锂离子电池的核心材料,研究了以可溶胀聚合物多孔膜作为骨架、在其孔道内填充凝胶结构而制备的锂离子导电膜。首先采用溶液相转化法制备了聚(偏氟乙烯-六氟丙烯)(PVDF-HFP)多孔膜,然后将多孔膜浸入含有锂盐、聚乙二醇二... 详细信息

锂离子导电膜是锂离子电池的核心材料,研究了以可溶胀聚合物多孔膜作为骨架、在其孔道内填充凝胶结构而制备的锂离子导电膜。首先采用溶液相转化法制备了聚(偏氟乙烯-六氟丙烯)(PVDF-HFP)多孔膜,然后将多孔膜浸入含有锂盐、聚乙二醇二丙烯酸酯(PEGDA)和过氧化苯甲酰的碳酸酯溶液吸收电解液,再加热引发PEGDA中双键交联得到具有多孔骨架和交联PEG的锂离子凝胶聚合物电解质膜(Li-GPEM)。失重、力学和及电化学性质分析表明,所制备的Li-GPEM的电导率为2.25mS/cm,综合性能优于PVDF-HFP多孔膜吸附液态锂盐溶液的体系和共混凝胶膜体系。

关键词：聚偏氟乙烯-六氟丙烯锂离子聚乙二醇凝胶电解质多孔膜

Warming intensified the effects of nitrogen addition on N_(2)O emissions from alpine meadow in the northern Qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第1期15卷 101-112页

作者： Ming-Jie LI Yi-Qing GE Hasbagan GANJURJAV Guo-Zheng HU Hong-bao WU Jun YAN Shi-Cheng HE Qing-zhu GAO Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China National Agricultural Experimental Station for Agricultural Environment Nagqu 852100China Ecology and Nature Conservation Institute Chinese Academy of ForestryBeijing 100091China College of Resource and Environment Anhui Science and Technology UniversityFengyang 233100China Nagqu Agriculture Animal Husbandryand Prataculture Science and Technology Research and Extension CenterNagqu 852100China Tongliao Experimental Middle School Tongliao 028000China

Warming and nitrogen(N)addition may impact soil nitrous oxide(N_(2)O)emissions,but the relationship between plant community composition and soil microbial activities remains *** a two-year field study in the Qinghai-Tibet Plateau,open-top chambers were used to quantify the effects of warming,N-addition,and their interactions on N_(2)O *** found that the N-addition greatly increased N_(2)O emissions by 77.4%in 2018 when compared to the control *** contrast,warming showed little effect on N_(2)0 emissions but did increase the activity of enzymes associated with soil nitrification and denitrification.A combined effect of warming and N-addition of resulted in 208.6%(2018)and 90.8%(2019)increase in N_(2)0 emissions,respectively,compared to the individual treatments of warming or *** warming in alpine meadows is causally linked to increased legume biomass which is further intensified with the *** legume biomass(p<0.05),soil moisture(p<0.001)and enzyme activity(p<0.001)had a positive effect on N_(2)0 emissions,while diminished microbial carbon/nitrogen(MBC/MBN)(p<0.05)correlated with reduced N_(2)O *** results indicated that N-addition has a positive effect on N_(2)O emissions,and the addition of warming further intensifies this *** increased dominance of legumes and microbial N content contributes to this *** outcomes suggest that warming and atmospheric N deposition can stimulate N_(2)O emissions of alpine meadows inthefuture.

关键词： Alpine meadow Community composition Nitrogen addition Nitrous oxide flux Qinghai-Tibet Plateau Warming

聚酰亚胺/钛酸钡复合膜介电性能及其影响因素的研究

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功能材料 2007年第7期38卷 1106-1109页

作者：刘卫东刘小芬朱宝库谢曙辉徐志康浙江师范大学化学与生命科学学院物理化学研究所浙江金华321004 浙江大学高分子科学研究所高分子合成与功能构造教育部重点实验室浙江杭州310027

通过硅烷偶联剂改性的BaTiO3粒子与聚酰胺酸溶液共混成膜、亚胺化后制备出高介电常数聚酰亚胺/BaTiO3复合膜。考察了BaTiO3粒子的体积分数、粒径大小、偶联剂的种类与用量、频率等对介电性能的影响。研究发现,通过使用偶联剂对BaTiO3粒... 详细信息

通过硅烷偶联剂改性的BaTiO3粒子与聚酰胺酸溶液共混成膜、亚胺化后制备出高介电常数聚酰亚胺/BaTiO3复合膜。考察了BaTiO3粒子的体积分数、粒径大小、偶联剂的种类与用量、频率等对介电性能的影响。研究发现,通过使用偶联剂对BaTiO3粒子进行表面改性、增加粒子的粒径都可以有效提高复合膜的介电常数,膜的介电常数随BaTiO3粒子的体积分数的增加而增加,由粒径为100nm改性Ba-TiO3制备的复合膜,BaTiO3的体积分数为0.5时,膜在10kHz电场中的介电常数达到35。

关键词：聚酰亚胺钛酸钡复合膜介电性能

有机/无机杂化纳米粒子共混改性聚偏氟乙烯多孔膜及其表面两性离子化的研究

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功能材料 2014年第6期45卷 65-69页

作者：朱丽静朱利平徐又一朱宝库陈亦力刘德祥浙江大学高分子科学与工程学系杭州210027 北京碧水源科技股份有限公司北京102206

通过表面引发的可逆-加成断裂链转移(RAFT)聚合,制备了聚甲基丙烯酸甲酯-聚甲基丙烯酸二甲氨乙酯嵌段共聚物(PMMA-b-PDMAEMA)接枝改性的有机/无机杂化二氧化硅纳米粒子(BCP-gSiO2NPs),并将其与聚偏氟乙烯(PVDF)溶液共混,通过传统的非溶... 详细信息

通过表面引发的可逆-加成断裂链转移(RAFT)聚合,制备了聚甲基丙烯酸甲酯-聚甲基丙烯酸二甲氨乙酯嵌段共聚物(PMMA-b-PDMAEMA)接枝改性的有机/无机杂化二氧化硅纳米粒子(BCP-gSiO2NPs),并将其与聚偏氟乙烯(PVDF)溶液共混,通过传统的非溶剂诱导相分离(NIPS)法制备PVDF/BCP-g-SiO2有机-无机杂化分离膜,进一步通过膜表面PDMAEMA链段与1,3-丙磺酸内酯之间的季胺化反应,实现了PVDF/BCP-g-SiO2有机-无机杂化膜的表面两性离子化。研究结果表明,BCP-g-SiO2NPs的引入以及膜表面的进一步两性离子化显著提高了PVDF膜的亲水性和抗污染性能,是PVDF超滤膜等相转化膜材料改性的有效方法。

关键词：有机-无机杂化纳米粒子聚偏氟乙烯表面两性离子化抗污染

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： bao-Ri Zhang Yong-Hua Shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Carbon materials for enhanced photothermal conversion:Preparation and applications on steam generation

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Materials Reports(Energy) 2024年第2期4卷 34-44页

作者： Jiayi zhu Liu Huang Feng bao Guanli Chen Kangjin Song Zheling Wang Hong Xia Jinping Gao Yibing Song Caizhen zhu Fushen Lu Tingting Zheng Muwei Ji College of Chemistry and Chemical Engineering Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou515063China School of Chemistry and Chemical Engineering Guangdong Pharmaceutical UniversityZhongshan528458China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen518060China Department of Pharmacy Shandong University of Traditional Chinese MedicineJinan250355China

Photothermal conversion attracted lots of attention in the past years and sorts of materials were explored to enhance photothermal *** the past years,solar-driven desalination by photothermal conversion was proposed to release the shortage of fresh water and then it was considered much more important to prepare photothermal materials on large scales with high performance and low *** this review,we summarized the works on carbon-based photothermal materials in the past years,including the preparation as well as their application in steam *** these works,we give an outlook on the difficulties and chances of how to design and prepare carbon-based photothermal materials.

关键词： Photothermal conversion Carbon Composites Solar energy Steam generation

Clinical observation of extraction-site incisional hernia after laparoscopic colorectal surgery

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 710-716页

作者： bao-Hang Fan Ke-Li Zhong Li-Jin zhu Zhao Chen Fang Li Wen-Fei Wu Second Clinical Medical College of Jinan University Jinan UniversityShenzhen 518020Guangdong ProvinceChina Department of Gastrointestinal Surgery Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina Department of Radiation Oncology Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina

BACKGROUND Laparoscopic colorectal cancer surgery increases the risk of incisional hernia(IH)at the tumor extraction *** To investigate the incidence of IH at extraction sites following laparoscopic colo-rectal cancer surgery and identify the risk factors for IH *** This study retrospectively analyzed the data of 1614 patients who underwent la-paroscopic radical colorectal cancer surgery with tumor extraction through the abdominal wall at our center between January 2017 and December ***-rences in the incidence of postoperative IH at different extraction sites and the risk factors for IH incidence were *** Among the 1614 patients who underwent laparoscopic radical colorectal cancer surgery,303(18.8%),923(57.2%),171(10.6%),and 217(13.4%)tumors were ex-tracted through supraumbilical midline,infraumbilical midline,umbilical,and off-midline *** these,52 patients developed IH in the abdominal wall,with an incidence of 3.2%.The incidence of postoperative IH was significantly higher in the off-midline incision group(8.8%)than in the middle incision groups[the supraumbilical midline(2.6%),infraumbilical midline(2.2%),and umbilical incision(2.9%)groups](χ^(2)=24.985;P<0.05).Univariate analysis showed that IH occurrence was associated with age,obesity,sex,chronic cough,incision infection,and combined diabetes,anemia,and hypopro-teinemia(P<0.05).Similarly,multivariate analysis showed that off-midline incision,age,sex(female),obesity,incision infection,combined chronic cough,and hypoproteinemia were independent risk factors for IH at the site of laparoscopic colorectal cancer surgery(P<0.05).CONCLUSION The incidence of postoperative IH differs between extraction sites for laparoscopic colorectal cancer *** infraumbilical midline incision is associated with a lower hernia rate and is thus a suitable tumor extraction site.

关键词： Incisional hernia Laparoscopy Colorectal cancer Incision infection