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Journal of Rare Earths 2024年第6期42卷 1020-1028,I0001页

作者： Yan Lei Guangzhi Zhang yitong yao Gaiqin Zhu Zhong Chen Jiangrong Dan Hua Liu Shuwang Duo School of Materials and Mechanical and Electrical EngineeringJiangxi Science and Technology Normal University Nanchang330013China

ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase method.The crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(A.oryzae)were investigated.It is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 nm.Ce^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is increased.The integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of A.oryzae cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.

关键词： Zns Quantum dots Doping First-principles calculations Aspergllus oryzae Rare earths

Stacked arrangement of substrate integrated waveguide cavity-backed semicircle patches for wideband circular polarization with filtering effect

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Frontiers of Information Technology & Electronic Engineering 2023年第5期24卷 759-766页

作者： yitong yao Gang DONG Zhangming ZHU Yintang YANG School of Microelectronics Xidian UniversityXi’an 710071China

We present a novel broadband circularly polarized(CP)antenna with filtering effect for X-and Kuband satellite wireless communication.The structure comprises a driven layer(also a filtering layer)and a stacked layer(also a CP layer).The bandpass filtering response consists of two radiation nulls,which is the combined effect of a substrate integrated waveguide(SIW)cavity-backed aperture and embedded driven patch.

关键词： waveguide polarization antenna

Surface repair of wide-bandgap perovskites for high-performance all-perovskite tandem solar cells

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Journal of Energy Chemistry 2024年第6期93卷 64-70,I0003页

作者： Xiaojing Lv Weisheng Li Jin Zhang Yujie Yang Xuefei Jia yitong Ji Qianqian Lin Wenchao Huang Tongle Bu Zhiwei Ren Canglang yao Fuzhi Huang Yi-Bing Cheng Jinhui Tong State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina Key Lab of Artificial Micro-and Nano-Structures of Ministry of Education of China School of Physics and TechnologyWuhan UniversityWuhan 430072HubeiChina Department of Electrical and Electronic Engineering Photonics Research Institute(PRI)Research Institute for Intelligent Wearable Systems(iWEAR)The Hong Kong Polytechnic University999077Hong KongChina Laboratory of Advanced Materials Fudan UniversityShanghai 200438China Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Foshan 528200GuangdongChina

Wide-bandgap(WBG)perovskite solar cells(PSCs)play a fundamental role in perovskite-based tandem solar cells.However,the efficiency of WBG PSCs is limited by significant open-circuit voltage losses,which are primarily caused by surface defects.In this study,we present a novel method for modifying surfaces using the multifunctional S-ethylisothiourea hydrobromide(SEBr),which can passivate both Pb^(-1)and FA^(-1)terminated surfaces,Moreover,the SEBr upshifted the Fermi level at the perovskite interface,thereby promoting carrier collection.This proposed method was effective for both 1.67 and 1.77 eV WBG PSCs,achieving power conversion efficiencies(PCEs)of 22.47%and 19.90%,respectively,with V_(OC)values of 1.28 and 1.33 V,along with improved film and device stability.With this advancement,we were able to fabricate monolithic all-perovskite tandem solar cells with a champion PCE of 27.10%,This research offers valuable insights for passivating the surface trap states of WBG perovskite through rational multifunctional molecular engineering.

关键词： Wide-bandgap perovskite Surface defect Multifunctional molecule All-perovskite tandem solar cells

Future biomass carbon sequestration capacity of Chinese forests

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Science Bulletin 2018年第17期63卷 1108-1117页

作者： yitong yao Shilong Piao Tao Wang Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University Beijing 100871 China Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Center for Excellence in Tibetan Earth Science Chinese Academy of Sciences Beijing 100085. China

Chinese forests, characterized by relatively young stand age, represent a significant biomass carbon(C)sink over the past several decades. Nevertheless, it is unclear how forest biomass C sequestration capacity in China will evolve as forest age, climate and atmospheric CO_2 concentration change continuously. Here,we present a semi-empirical model that incorporates forest age and climatic factors for each forest type to estimate the effects of forest age and climate change on total forest biomass, under three different scenarios based on the fifth phase of the Coupled Model Intercomparison Project(CMIP5). We estimate that age-related forest biomass C sequestration to be 6.69 Pg C(~0.17 Pg C a^(-1)) from the 2000s to the 2040s.Climate change induces a rather weak increase in total forest biomass C sequestration(0.52–0.60 Pg C by the 2040s). We show that rising CO_2 concentrations could further increase the total forest biomass C sequestration by 1.68–3.12 Pg C in the 2040s across all three scenarios. Overall, the total forest biomass in China would increase by 8.89–10.37 Pg C by the end of 2040s. Our findings highlight the benefits of Chinese afforestation programs, continued climate change and increasing CO_2 concentration in sustaining the forest biomass C sink in the near future, and could therefore be useful for designing more realistic climate change mitigation policies such as continuous forestation programs and careful choice of tree species.

关键词：中国森林生物资源能力气候变化年龄相关碳联合模型年代表

The polycaprolactone/silk fibroin/carbonate hydroxyapatite electrospun scaffold promotes bone reconstruction by regulating the polarization of macrophages

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Regenerative Biomaterials 2022年第1期9卷 533-547页

作者： Xiaoshi Jia Jing Zhou Jinqiu Ning Maoquan Li yitong yao Xiaodong Wang Yutao Jian Ke Zhao Department of Prosthodontics Guanghua School of StomatologyHospital of StomatologySun Yat-sen UniversityGuangzhouGuangdong 510055China Guangdong Provincial Key Laboratory of Stomatology GuangzhouGuangdong 510055China

Macrophages are known to modulate the osteogenic environment of bone regeneration elicited by biological bone grafts.Alteration in certain chemical components tends to affect macrophages polarization.Comparatively to hydroxyapatite(HAp),carbonate hydroxyapatite(CHA)consists of 7.4(wt%)carbonate ions and more closely resembles the mineral content of bone.It remains unknown whether CHA scaffolds or HA scaffolds have better osteogenic properties.In this study,we fabricated PCL/SF scaffold,PCL/SF/HAp scaffold and PCL/SF/CHA scaffold using the electrospinning technique.Despite comparable mechanical properties,the PCL/SF/CHA scaffold exhibited better osteogenic properties than the PCL/SF/HAp scaffold.Although no significant differences were observed between the two scaffolds for promoting osteoblast differentiation in vitro,the PCL/SF/CHA group appeared to be more effective at promoting bone regeneration in cranial defects in vivo.The PCL/SF/CHA scaffold was found to promote macrophage polarization toward M2 via activating the JAK/STAT5 pathway which caused a pro-osteogenic microenvironment to facilitate osteoblast differentiation.The results of this study indicated a higher potential of CHA to substitute HAp in the production of bone scaffolds for better bone regeneration.

关键词： bone reconstruction PCL/SF/CHA scaffold macrophage polarization electrospinning

中国肉鸭产业绿色全要素生产率测算及区域差异分析

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中国家禽 2024年第6期46卷 56-64页

作者：姚懿桐林昊刘灵芝唐山工业职业技术学院河北唐山063299 华中农业大学湖北武汉430070

为提高我国24个肉鸭主产省(市、区)的环境技术效率和绿色全要素生产率,研究基于2020和2021年我国24个肉鸭主产省(市、区)的肉鸭养殖投入产出数据,利用超效率SBM模型和ML指数,分别对我国肉鸭产业环境技术效率和绿色全要素生产率进行测算... 详细信息

为提高我国24个肉鸭主产省(市、区)的环境技术效率和绿色全要素生产率,研究基于2020和2021年我国24个肉鸭主产省(市、区)的肉鸭养殖投入产出数据,利用超效率SBM模型和ML指数,分别对我国肉鸭产业环境技术效率和绿色全要素生产率进行测算,将其与不考虑非期望产出的测算结果对比,分析肉鸭产业绿色发展总体情况及省际、区域差异。结果显示:①从环境技术效率来看,我国肉鸭养殖技术效率总体在改善,我国大部分肉鸭主产省(市、区)实现决策充分有效,但存在环境技术投入相对不足问题。环境技术效率呈现东中西递减趋势,北方高于南方,各区域内仍存在产业发展与环境不协调问题,忽视环境约束会使肉鸭养殖效率高估;②从绿色全要素生产率来看,我国肉鸭产业绿色全要素生产率出现增长但整体增长形势并不乐观,产业面临技术进步放缓,增长的动力主要依靠绿色技术效率改善,增长速度也呈现东中西递减趋势,北方高于南方,区域差距体现在绿色技术进步上。研究表明,我国肉鸭产业绿色全要素生产率存在很大提升空间,要从技术创新投入、技术推广入手,因地制宜制定绿色全要素生产率提升策略,发挥环境规制的作用。

关键词：肉鸭环境技术效率绿色全要素生产率超效率SBM 区域差异

百香果皮分级萃取物中多酚轮廓分析及其抗氧化活性物质筛选

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食品工业科技 2024年第1期45卷 18-27页

作者：么亚妹陈奕彤田永涛刘天悦王文蜀质谱成像与代谢组学国家民委重点实验室(中央民族大学) 北京100081 中央民族大学生命与环境科学学院北京100081

为探究不同溶剂对百香果皮多酚的萃取效率,寻找其中抗氧化活性贡献大的特征多酚。选用石油醚、乙酸乙酯和正丁醇分级萃取百香果皮乙醇粗提物,采用分光光度法分别测定其总酚总黄酮含量,借助超高效液相色谱串联质谱解析各分级萃取物中酚... 详细信息

为探究不同溶剂对百香果皮多酚的萃取效率,寻找其中抗氧化活性贡献大的特征多酚。选用石油醚、乙酸乙酯和正丁醇分级萃取百香果皮乙醇粗提物,采用分光光度法分别测定其总酚总黄酮含量,借助超高效液相色谱串联质谱解析各分级萃取物中酚类化合物,并结合非靶向代谢组学技术筛选差异代谢物并定量。选用DPPH自由基清除、ABTS^(+)自由基清除和Fe^(2+)还原法分析各分级萃取物体外抗氧化活性差异,通过皮尔逊相关性分析探寻百香果皮中抗氧化活性酚类标志物。结果表明:各萃取物总酚和总黄酮含量差异显著(P正丁醇部位(BE)>乙醇粗提物(CE)>水部位(WE)>石油醚部位(PE)。从CE和各分级萃取物中共鉴定出33个酚类化合物,CE、EE和BE酚类化合物种类和数量较多。主成分分析(PCA)区分了各萃取物的代谢物,正交偏最小二乘法判别分析(OPLS-DA)对羟基苯甲酸、原儿茶酸、异槲皮苷和异荭草苷为差异物。EE中对羟基苯甲酸(653.44μg/g)、异槲皮苷(2420.64μg/g)和异荭草苷(113.23μg/g)含量最高,CE中原儿茶酸(152.40μg/g)含量最高。百香果皮各分级萃取物体外抗氧化活性差异显著,EE体外抗氧化能力最强,是优质的抗氧化剂开发部位。相关性分析结果显示,总酚和总黄酮是百香果皮抗氧化活性物质基础,异荭草苷和异槲皮苷是其中的抗氧化活性酚类标志物。研究结果为建立百香果皮相关抗氧化产品质量控制标准及精准开发利用百香果皮酚类化合物资源提供了基础数据。

关键词：百香果皮分级萃取超高效液相色谱串联质谱技术(UPLC-MS) 多酚化合物主成分分析(PCA) 抗氧化

金属离子对Trichoderma longibrachiatum UN32石斛碱型生物碱产量的影响

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食品与发酵工业 2024年第6期50卷 226-232页

作者：秦一彤余娧凡钱旭姚云君金磊磊陈集双虞龙南京工业大学生物与制药工程学院江苏南京211800 遵义医科大学生物资源健康利用研究中心贵州遵义563000

石斛碱是传统植物金钗石斛(Dendrobium nobile)的特征药用活性成分,结构上属于石斛型生物碱(dendrobine-type total alkaloids,DTTAs)。石斛碱的积累受周期和环境的影响,仅从植物中获取难以满足需求。该研究的对象Trichoderma longibrac... 详细信息

石斛碱是传统植物金钗石斛(Dendrobium nobile)的特征药用活性成分,结构上属于石斛型生物碱(dendrobine-type total alkaloids,DTTAs)。石斛碱的积累受周期和环境的影响,仅从植物中获取难以满足需求。该研究的对象Trichoderma longibrachiatum UN32是实验室前期通过复合诱变获得的产DTTAs的正突变株。为提高UN32的生物碱产量,使产物表达水平趋于稳定,该研究从UN32发酵培养基中无机盐的添加量出发,利用响应面法确定金属离子的最优配比。根据Plackett-Burman法设计筛选出对响应结果影响程度最显著的3个因素分别为Zn^(2+)、Cu^(2+)、Fe^(2+),其最佳添加时间和添加浓度分别是Cu^(2+)0.5 mmol/L(第6天)、Fe^(2+)0.4 mmol/L(第6天)和Zn^(2+)0.7 mmol/L(第3天)。响应面统计的结果显示,当模型响应值生物碱量达最大值时,Cu^(2+)、Zn^(2+)和Fe^(2+)的浓度分别为0.54、0.69、0.39 mmol/L,此时生物碱产量达到(317.36±6.48)μg,比初始培养基提高了72.68%。综上,金属离子及其不同组合对菌株UN32生物碱的积累具有促进作用,该方法具有较好的开发价值和应用前景。

关键词：长枝木霉内生真菌石斛型生物碱金属离子响应面优化

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打印微结构对表面电荷积聚特性的影响

高电压技术 2024年第5期50卷 2237-2246页

作者：姚亦桐杨洋牛广乾钱志源刘承山穆海宝西安交通大学电工材料电气绝缘全国重点实验室西安710049 上海宇航系统工程研究所上海201109

航天器等真空设备面临着高电压、小型化的发展需求,但其中的固体-真空绝缘界面容易发生真空沿面闪络。为了提升真空绝缘的沿面耐电性能,通过3D打印技术在绝缘介质表面构建了微刻槽和打印金属两种微结构,并通过电荷积聚实验研究发现了打... 详细信息

航天器等真空设备面临着高电压、小型化的发展需求,但其中的固体-真空绝缘界面容易发生真空沿面闪络。为了提升真空绝缘的沿面耐电性能,通过3D打印技术在绝缘介质表面构建了微刻槽和打印金属两种微结构,并通过电荷积聚实验研究发现了打印微结构能有效抑制表面电荷积聚过程;同时,改变微刻槽数量以及金属的宽度和数量,进一步通过实验对比研究了参数不同时的情况,发现增加微结构的数量和宽度均有利于提升其对电荷积聚的抑制效果;最后,构建真空沿面闪络粒子仿真模型,通过研究电子运动和二次电子崩的发展,并结合实验结果发现微结构能够散射电子,从而产生抑制电荷积聚、提升沿面耐电强度的效果。

关键词：真空沿面闪络 3D打印打印微结构电荷积聚二次电子崩耐电强度

蛹虫草磷酸甲羟戊酸激酶和焦磷酸甲羟戊酸脱羧酶基因的功能分析

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微生物学报 2024年第2期64卷 461-472页

作者：闫欢欢尚怡彤王丽红田学琴姚丽华曾斌胡志宏江西科技师范大学生命科学学院江西南昌330013 江西科技师范大学江西省生物加工过程重点实验室江西南昌330013 深圳技术大学药学院广东深圳518118

【目的】确定蛹虫草甲羟戊酸途径中的2个关键酶——磷酸甲羟戊酸激酶(CmErg8)和焦磷酸甲羟戊酸脱羧酶(CmErg19)的功能及其对麦角甾醇和虫草素含量的影响。【方法】通过生物信息学分析鉴定蛹虫草中CmErg8和CmErg19,并采用酵母互补确定其... 详细信息

【目的】确定蛹虫草甲羟戊酸途径中的2个关键酶——磷酸甲羟戊酸激酶(CmErg8)和焦磷酸甲羟戊酸脱羧酶(CmErg19)的功能及其对麦角甾醇和虫草素含量的影响。【方法】通过生物信息学分析鉴定蛹虫草中CmErg8和CmErg19,并采用酵母互补确定其功能是否保守;以蛹虫草尿嘧啶营养缺陷型CmΔpyrG为背景菌株,利用农杆菌介导的转化方法对CmErg8和CmErg19进行过表达,观察其对麦角甾醇和虫草素含量的影响。【结果】CmErg8和CmErg19不能互补酵母erg8和erg19突变体的温度敏感表型;CmErg8和CmErg19过表达菌株中麦角甾醇和虫草素含量均有所增加,特别是CmErg19基因过表达可以使虫草素含量提升5倍左右。【结论】本研究揭示了蛹虫草CmErg8和CmErg19的功能,并且发现蛹虫草麦角甾醇合成通路基因可能会影响虫草素含量。

关键词：蛹虫草磷酸甲羟戊酸激酶焦磷酸甲羟戊酸脱羧酶麦角甾醇虫草素