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Understory plant diversity and phenolic allelochemicals across a range of Eucalyptus grandis plantation ages

林业研究:英文版 2023年第5期34卷 1577-1590页

作者： Jinjin Li Yumei Huang Lianghua Chen shun gao Jian Zhang Danju Zhang Sichuan Provincial Key Laboratory of Ecological Forestry Engineering College of ForestrySichuan Agricultural UniversityWenjiang 611130ChengduChina College of Landscape Architecture Sichuan Agricultural UniversityWenjiang 611130ChengduChina

Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory diversity.Phenolic compounds are the main allelochemicals suppressing understory plants.However,the dynamic changes in phenolic allelochemicals and their relationship with understory diversity with increasing age of Eucalyptus plantations remain largely unclear.In this study,the understory plant diversity was assessed and phenolic compounds identified from leaf litter,roots,and rhizosphere soil samples in a Eucalyptus grandis plantation at two-year intervals for ten years using ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The abundance and diversity of under story plant species were lowest in 4-year-old plantations and increased significantly with age.Seven phenolic acids and 10 flavonoids were identified from leaf litter,roots,and rhizosphere soils.Most of the potential phenolic allelochemicals,such as salicylic acid,gallic acid,4-hydroxybenzoic acid,and epicatechin,were more abundant in younger plantations,especially at4 years old.The concentrations of phenolic compounds in the rhizosphere zone were significantly lower than in litter and root samples and did not change significantly with an increase in age.Notably,phenolic compounds contributed more to the variation in the understory plants than soil factors.Hydroxyphenyllactic acid,ellagic acid,quercetin,salicylic acid,and 4-hydroxybenzoic acid were the main phenolic compounds explaining the variation in plant diversity with plantation age.These findings indicate that young E.grandis plantations,especially at four years of age,merit a greater focus because of their lower understory plant diversity and higher allelopathic potential.

关键词： Eucalyptus grandis Phenolic compounds Understory plant diversity Plantation age

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融合信息物理社会因素的配电网可靠性评估方法

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电力系统自动化 2024年第3期48卷 51-61页

作者：卢俞帆刘念高舜安新能源电力系统国家重点实验室(华北电力大学) 北京市102206 国网冀北电力有限公司北京市100054

为分析重大社会活动中信息系统先进技术和社会系统应急保电措施对配电网可靠性的影响,文中提出融合信息物理社会因素的配电网可靠性评估方法。首先,为分析信息物理社会系统的相互作用,构建了配电网可靠性的信息物理社会交互框架。然后,... 详细信息

为分析重大社会活动中信息系统先进技术和社会系统应急保电措施对配电网可靠性的影响,文中提出融合信息物理社会因素的配电网可靠性评估方法。首先,为分析信息物理社会系统的相互作用,构建了配电网可靠性的信息物理社会交互框架。然后,通过构建设备发展型和破坏型故障状态转移模型,量化了信息系统中缺陷诊断、风险预警技术作用周期以及社会系统中检修人员技术水平与设备故障率的关系。通过构建设备故障恢复时间模型,量化了信息系统中故障定位技术精度以及社会系统中交通路况、应急物资充裕度与设备故障恢复时间的关系。最后,为了验证框架和模型的有效性,文中建立了一个包含信息物理社会系统基本信息的测试系统。结果验证了信息、社会系统对配电物理系统可靠性的提升作用。

关键词：配电网可靠性评估信息物理社会系统缺陷诊断应急保电

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Recent Advances and Perspective on Design and Synthesis of Electrode Materials for Electrochemical Sensing of Heavy Metals

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Energy & Environmental Materials 2018年第3期1卷 113-131页

作者： Huijie Hou Kemal M.Zeinu shun gao Bingchuan Liu Jiakuan Yang Jingping Hu School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Hubei Provincial Engineering Laboratory of Solid Waste Treatment Disposal and RecyclingWuhan 430074China Kombolcha Institute of Technology Wollo UniversityP.O.Box 208KombolchaEthiopia

The increase in release of toxic heavy metals into natural water attracts much attention due to its devastating effect on ecology and human health.The design and implementation of green electrode materials is pivotal ... 详细信息

关键词： bismuth electrochemical sensing environmental monitoring heavy metals nanostructured materials

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大学物理线上教学学生内驱力的培养策略研究

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大学物理 2024年第2期43卷 44-48页

作者：李刚高顺起天津财经大学理工学院天津300222

线上教学以其独特优势,成为疫情下教学正常开展的必然选择,也是后疫情时代线下教学的有益补充.通过激发和培养学生的内驱力,将极大增加学生的线上学习主动性,提高学习效率,从而提高课堂教学的有效性.本文以大学物理课程为例,阐述了线上... 详细信息

线上教学以其独特优势,成为疫情下教学正常开展的必然选择,也是后疫情时代线下教学的有益补充.通过激发和培养学生的内驱力,将极大增加学生的线上学习主动性,提高学习效率,从而提高课堂教学的有效性.本文以大学物理课程为例,阐述了线上教学中学生内驱力的培养策略,为开展线上线下混合式教学提供有益启示.

关键词：线上教学内驱力大学物理培养策略

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铜尾矿/聚磷酸铵阻燃聚氨酯的制备及研究

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塑料工业 2024年第5期52卷 90-97页

作者：沈海峰高顺王国栋高业访付存龙刘秀玉唐刚安徽工业大学建筑工程学院安徽马鞍山243002

以聚磷酸铵(APP)/铜尾矿(CTS)为阻燃体系,采用一步全水发泡法制备硬质聚氨酯泡沫/聚磷酸铵/铜尾矿(RPUF/APP/CTS)复合材料。阻燃测试表明,RPUF-30APP的极限氧指数(LOI)达到24.0%,垂直燃烧测试达到V-0级别,其阻燃性明显提高。锥形量热测... 详细信息

以聚磷酸铵(APP)/铜尾矿(CTS)为阻燃体系,采用一步全水发泡法制备硬质聚氨酯泡沫/聚磷酸铵/铜尾矿(RPUF/APP/CTS)复合材料。阻燃测试表明,RPUF-30APP的极限氧指数(LOI)达到24.0%,垂直燃烧测试达到V-0级别,其阻燃性明显提高。锥形量热测试表明,RPUF-30APP的热释放速率峰值(PHRR)由纯样的300.5 kW/m^(2)降低至139.4 kW/m^(2),下降幅度高达53.6%;总热释放(THR)由纯样的40.0 MJ/m^(2)下降至28.1 MJ/m^(2),降低幅度高达29.8%,表明APP/CTS体系明显降低复合材料燃烧过程中的热释放,其火灾安全性提高。炭渣分析表明,CTS/APP/RPUF复合材料燃烧过程中形成了致密的炭层,提高了复合材料的阻燃性能。该研究为CTS提供了一个新的应用领域,并为提高聚合物的防火安全性铺平了道路。

关键词：硬质聚氨酯泡沫聚磷酸铵铜尾矿复合材料阻燃

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Fast Determination of the Rubber Content in Taraxacum kok-saghyz Fresh Biomass Using Portable Near-Infrared Spectroscopy and Pyrolysis-Gas Chromatography

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Journal of Analysis and Testing 2022年第4期6卷 393-400页

作者： Ying Chen shun-Kai gao Yi-Yang Dong Xiang Ma Jia-Ru Li Min-Min Guo Ji-Chuan Zhang College of Life Science and Technology Rubber Plant Research CenterBeijing University of Chemical TechnologyBeijing100029China College of Materials and Engineering Beijing University of Chemical TechnologyBeijing100029China

Taraxacum kok-saghyz(TKS)is a plant native to the Tianshan valley on the border between China and Kazakhstan.TKS rubber is a good substitute for natural rubber.TKS's breeding work necessitates the need to screen high-yielding varieties,hence rapid determination of rubber content is essential for the screening.Conventional analytical methods cannot meet actual needs in terms of real-time testing and economic cost.Near-infrared spectroscopy analysis technology,which has developed rapidly in the field of industrial process analysis in recent years,is a green detection technology with obvious merits of fast measurement speed,low cost and no sample loss.This research aims to develop a portable non-destructive near-infrared spectroscopic detection scheme to evaluate the content of natural rubber in TKS fresh roots.Pyrolysis gas chromatography(Py-GC)was chosen as the reference method for the development of NIR prediction model.208 TKS fresh root samples were collected from the Inner Mongolia Autonomous Region of China.Near-infrared spectra were acquired for all samples.Randomly,two-thirds of them were selected as the calibration set,the remaining one-third as the validation set,and the partial least squares method was successfully established a good NIR prediction model for rubber content at 1080-1800 nm with a ratio of performance to deviation(RPD)of 5.54 and coefficient of determination(R^(2))of 0.95.This study showed that portable near-infrared spectroscopy could be used with ease for large-scale screening of TKS plants in farmland,and could greatly facilitate TKS germplasm preservation,high-yield cultivation,environment-friendly,high-efficiency and low-cost rubber extraction,and comprehensive advancement of the natural rubber industry thereof.

关键词： Taraxacum kok-saghyz Rubber Near-infrared spectroscopy Pyrolysis gas chromatography

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湘东北仁里- 传梓源地区锂、铌钽矿找矿远景浅析

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世界有色金属 2024年第11期 94-96页

作者：林跃徐美玲王延波高顺王奇金湖南省地质灾害调查监测所湖南长沙410000 湖南省核地质调查所湖南长沙410000

仁里-传梓源地区位于湘东北幕阜山岩体南缘,是湖南省最具潜力的花岗伟晶岩型稀有金属成矿区域,目前已发现仁里大型铌钽矿、传梓源中型锂铍铌钽矿等稀有金属矿床。该地区位于江南新元古代造山带中段,稀有金属成矿与燕山期岩浆活动有关,具... 详细信息

仁里-传梓源地区位于湘东北幕阜山岩体南缘,是湖南省最具潜力的花岗伟晶岩型稀有金属成矿区域,目前已发现仁里大型铌钽矿、传梓源中型锂铍铌钽矿等稀有金属矿床。该地区位于江南新元古代造山带中段,稀有金属成矿与燕山期岩浆活动有关,具有LCT伟晶岩典型分带特征,根据这一特征结合稀有金属成矿规律,对周边地区进行综合分析,圈定稀有金属找矿远景区。通过地质勘查和科研等工作,该地区有望成为湖南省重要的花岗伟晶岩型稀有金属矿田。

关键词：锂铌钽矿找矿远景湘东北仁里-传梓源伟晶岩

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Conservative resection for benign tumors of the proximal pancreas

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World Journal of Gastroenterology 2009年第32期15卷 4044-4048页

作者： Hai Huang Xin Dong shun-Liang gao Yu-Lian Wu Department of Surgery. Second Affiliated Hospital College of Medicine Zhejiang University 88 Jiefang Road Hangzhou 310009 Zhejiang Province China

AIM:To evaluate the safety and long-term prognosis of conservative resection (CR) for benign or borderline tumor of the proximal pancreas.METHODS: We retrospectively analyzed 20 patients who underwent CR at the Second Affi liated Hospital of Zhejiang University School of Medicine between April 2000 and October 2008. For pancreaticojejunostomy, a modified invagination method, continuous circular invaginated pancreaticojejunostomy (CCI-PJ) was used. Modified continuous closed lavage (MCCL) was performed for patients with pancreatic fistula.RESULTS: The indications were: serous cystadenomas in eight patients, insulinomas in six, non-functional islet cell tumors in three and solid pseudopapillary tumors in three. Perioperative mortality was zero and morbidity was 25%. Overall, pancreatic fistula was present in 25% of patients. At a mean follow up of 42.7 mo, all patients were alive with no recurrence and no new-onset diabetes mellitus or exocrine dysfunction.CONCLUSION: CR is a safe and effective procedure for patients with benign tumors in the proximal pancreas, with careful CCI-PJ and postoperative MCCL.

关键词：良性肿瘤切除术胰腺保守浙江大学肠吻合术胰岛细胞乳头状瘤

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Green manuring relocates microbiomes in driving the soil functionality of nitrogen cycling to obtain preferable grain yields in thirty years

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Science China(Life Sciences) 2024年第3期67卷 596-610页

作者： Guopeng Zhou Kunkun Fan Songjuan gao Danna Chang Guilong Li Ting Liang Hai Liang shun Li Jiudong Zhang Zongxian Che Weidong Cao State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China Institute of Soil&Fertilizer and Resource&Environment Jiangxi Academy of Agricultural SciencesNanchang 330200China Institute of Soil and Fertilizer and Water-saving Agriculture Gansu Academy of Agricultural SciencesLanzhou 730070China

Fertilizers are widely used to produce more food, inevitably altering the diversity and composition of soil organisms. The role of soil biodiversity in controlling multiple ecosystem services remains unclear, especially after decades of fertilization. Here, we assess the contribution of the soil functionalities of carbon(C), nitrogen(N), and phosphorus(P) cycling to crop production and explore how soil organisms control these functionalities in a 33-year field fertilization experiment. The long-term application of green manure or cow manure produced wheat yields equivalent to those obtained with chemical N, with the former providing higher soil functions and allowing the functionality of N cycling(especially soil N mineralization and biological N fixation) to control wheat production. The keystone phylotypes within the global network rather than the overall microbial community dominated the soil multifunctionality and functionality of C,N, and P cycling across the soil profile(0–100 cm). We further confirmed that these keystone phylotypes consisted of many metabolic pathways of nutrient cycling and essential microbes involved in organic C mineralization, N_(2)O release, and biological N fixation. The chemical N, green manure, and cow manure resulted in the highest abundances of amoB, nifH, and GH48 genes and Nitrosomonadaceae,Azospirillaceae, and Sphingomonadaceae within the keystone phylotypes, and these microbes were significantly and positively correlated with N_(2)O release, N fixation, and organic C mineralization, respectively. Moreover, our results demonstrated that organic fertilization increased the effects of the network size and keystone phylotypes on the subsoil functions by facilitating the migration of soil microorganisms across the soil profiles and green manure with the highest migration rates. This study highlights the importance of the functionality of N cycling in controlling crop production and keystone phylotypes in regulating soil functions, and provides selectable fertilization strategies f

关键词： soil biodiversity soil multifunctionality element cycling keystone phylotypes

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Central pancreatectomy for benign or low-grade malignant pancreatic tumors in the neck and body of the pancreas

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World Journal of Gastrointestinal Surgery 2022年第9期14卷 896-903页

作者： Yi-Wen Chen Jian Xu Xiang Li Wei Chen shun-Liang gao Yan Shen Min Zhang Jian Wu Ri-Sheng Que Jun Yu Ting-Bo Liang Xue-Li Bai Department of Hepatobiliary and Pancreatic Surgery The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina Department of Pancreatic Disease Zhejiang Provincial Key LaboratoryHangzhou 310000Zhejiang ProvinceChina The Study of Pancreatic Disease Zhejiang Provincial Innovation CenterHangzhou 310000Zhejiang ProvinceChina The Study of Hepatobiliary&Pancreatic Diseases Zhejiang Provincial Clinical Research CenterHangzhou 310003Zhejiang ProvinceChina Cancer Center Zhejiang UniversityHangzhou 310058Zhejiang ProvinceChina

BACKGROUND For tumors in the neck and body of the pancreas,distal pancreatectomy(DP)has been the standard surgical procedure for the last few decades and central pancreatectomy(CP)is an alternative surgical option.Whether CP better preserves remnant pancreatic endocrine and exocrine functions after surgery remains a subject of debate.AIM To evaluate the safety and efficacy of CP compared with DP for benign or lowgrade malignant pancreatic tumors in the neck and body of the pancreas.METHODS This retrospective study enrolled 296 patients who underwent CP or DP for benign and low-malignant neoplasms at the same hospital between January 2016 and March 2020.Perioperative outcomes and long-term morbidity of endocrine/exocrine function were prospectively evaluated.RESULTS No significant difference was observed in overall morbidity or clinically relevant postoperative pancreatic fistula between the two groups(P=0.055).Delayed gastric emptying occurred more frequently in the CP group than in the DP group(29.4%vs 15.3%;P<0.005).None of the patients in the CP group had new-onset or aggravated distal metastasis,whereas 40 patients in the DP group had endocrine function deficiency after surgery(P<0.05).There was no significant difference in the incidence of diarrhea immediately after surgery,but at postoperative 12 mo,a significantly higher number of patients had diarrhea in the DP group than in the CP group(0%vs 9.5%;P<0.05).CONCLUSION CP is a generally safe procedure and is better than DP in preserving long-term pancreatic endocrine and exocrine functions.Therefore,CP might be a better option for treating benign or low-grade malignant neoplasms in suitable patients.

关键词： Central pancreatectomy Distal pancreatectomy Endocrine function Exocrine function Morbidity

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