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Ecosystem service values of gardens in the Yellow River Basin,China

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Journal of Arid Land 2022年第3期14卷 284-296页

作者： GE qianqian xu Wenjie FU Meichen HAN Yingxin AN Guoqiang xu Yuetong School of Land Science and Technology China University of Geosciences(Beijing)Beijing 100083China China Land Surveying and Planning Institute Beijing 100035China Shandong Urban and Rural Planning Design Institute Jinan 250013China Territorial Spatial Planning Institute of Shandong Province Jinan 250014China College of Geography and Environment Shandong Normal UniversityJinan 250358China Key Laboratory of Land Use Ministry of Natural ResourcesShandong BasisJinan 250014China

Studies on the ecosystem service value(ESV)of gardens are critical for informing evidence-based land management practices based on an understanding of the local ecosystem.By analyzing equivalent value factors(EVFs),this paper evaluated the values of 11 ecosystem services of gardens in the Yellow River Basin of China in 2019.High-precision land use survey data were used to improve the accuracy of the land use classification,garden areas,and spatial distribution of the ESVs of gardens.The results showed that garden ecosystem generally had high ESVs,especially in terms of the ESV of food production,which is worthy of further research and application to the practice of land use planning and management.Specifically,the value of one standard EVF of ecosystem services in 2019 was 3587.04 CNY/(hm^(2)·a),and the ESV of food production of gardens was much higher than that of croplands.Garden ecosystem provided an ESV of 1348.66×10^(8)CNY/a in the Yellow River Basin.The areas with the most concentrated ESVs of gardens were located in four regions:downstream in the Shandong-Henan zone along the Yellow River,mid-stream in the Shanxi-Shaanxi zone along the Yellow River,the Weihe River Basin,and upstream in the Qinghai-Gansu-Ningxia-Inner Mongolia zone along the Yellow River.The spatial correlation of the ESVs in the basin was significant(global spatial autocorrelation index Moran's I=0.464),which implied that the characteristics of high ESVs adjacent to high ESVs and low ESVs adjacent to low ESVs are prominent.In the Yellow River Basin,the contribution of the ESVs of gardens to the local environment and economy varied across regions.We also put forward some suggestions for promoting the construction of ecological civilization in the Yellow River Basin.The findings of this study provide important contributions to the research of ecosystem service evaluation in the Yellow River Basin.

关键词： ecosystem service evaluation garden ecosystem equivalent value factors spatial autocorrelation analysis Yellow River Basin

Macro Debt Burden and Consumption Expansion:An Analysis Based on Panel Model and Panel Quantile Regression Model

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China Finance and Economic Review 2021年第1期10卷 26-43页

作者： qianqian Lu Kun xu Guangjian xu School of Public Administration and Policy Renmin University of China

As the level of social credit burden rises,to ease the liquidity constraint for residents is currently an important way to boost the domestic demand in China.This paper uses the panel data of Chinese provincial-level administrative units in 2007−2017 and adopts the panel regression model and panel quantile regression model to empirically analyze the relationship between debt burden level and average propensity to consume(APC).The result shows that increase in the level of macro debt burden can significantly improve the APC of residents;the marginal promoting effect of macro debt burden for the APC is in a V-shaped structure;such marginal influence differs evidently in different areas,with the marginal promoting effect turning out most prominent in the northeast of China.Accordingly,it’s suggested for government to keep refining the credit market,increase residents’income in multiple means,guide supply of liquidity towards the real economy and promote equalization of basic public services,so as to realize the expansion and upgrade of consumption.

关键词： macro debt burden consumption expansion regional heterogeneity panel quantile regression model

Magnetic manganese-based composites with multiple loss mechanisms towards broadband absorption

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Nano Research 2022年第6期15卷 5590-5600页

作者： Yue Liu Zirui Jia qianqian Zhan Yuhao Dong Qimeng xu Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China Weihai Innovation Institute Qingdao UniversityWeihai 264200China School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China

The weak dielectric properties and the lack of magnetic loss of manganese-based absorbers are obstructed as the new generation of electromagnetic wave absorption(EMA)materials applying in microelectronic devices.Herein,the sulfuration and subsequent compounding strategies have been employed to enhance the EMA performance of multi-shell nanosphere-shaped Mn_(2)O_(3)materials.With the narrow bandgap,the as-obtained MnS possesses reinforced electrical conductivity,which is conducive to conductivity loss.More importantly,the presence of potential difference between different phases will form space charge region at the heterogeneous interface,thus favoring interfacial polarization.Additionally,the improvement of magnetic loss is attributed to the presence of Co_(3)O_(4)nanoparticles.Consequently,the composites present enhanced EMA performance than original Mn_(2)O_(3).Specifically,the minimum reflection loss of as-prepared composites is−51.4 dB at the thickness of 1.8 mm and the broad effective absorption bandwidth reaches 6.2 GHz at 1.9 mm.The low matching thickness and high absorption efficiency in this work can provide a convincing reference when designing distinguished manganese-based absorbers.

关键词： manganese-based composites core@shell structure space charge polarization dielectric loss electromagnetic wave absorption

Source apportionment and suitability evaluation of seasonal VOCs contaminants in the soil around a typical refining-chemical integration park in China

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Journal of Environmental Sciences 2024年第3期137卷 651-663页

作者： xu Zhao Jing Meng qianqian Li Guijin Su Qifan Zhang Bin Shi Lingwen Dai Yong Yu Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring China National Environmental Monitoring CenterBeijing 100012China

Accurate source apportionment of volatile organic compounds(VOCs)in soil nearby petrochemical industries prevailing globally,is critical for preventing pollution.However,in the process,seasonal effect on contamination pathways and accumulation of soil VOCs is often neglected.Herein,Yanshan Refining-Chemical Integration Park,including a carpet,refining,synthetic rubber,and two synthetic resin zones,was selected for traceability.Season variations resulted in a gradual decrease of 31 VOCs in soil from winter to summer.A method of dry deposition resistance model coupling partitioning coefficient model was created,revealing that dry deposition by gas phase was the primary pathway for VOCs to enter soil in winter and spring,with 100 times higher fux than by particle phase.Source profiles for five zones were built by gas sampling with distinct substance indicators screened,which were used for positive matrix factorization factors determination.Contributions of the five zones were 14.9%,20.8%,13.6%,22.1%,and 28.6%in winter and 33.4%,12.5%,10.7%,24.9%,and 18.5%in spring,respectively.The variation in the soil sorption capacity of VOCs causes inter-seasonal differences in contribution.The better correlation between dry deposition capacity and soil storage of VOCs made root mean square and mean absolute errors decrease averagely by 8.8%and 5.5%in winter compared to spring.This study provides new perspectives and methods for the source apportionment of soil VOCs contamination in industrial sites.

关键词： Dry deposition resistance model Positive matrix factorization model Partitioning coefficient model Contamination pathway Source profile

Recent advances in hydrothermal modification of calcium phosphorus coating on magnesium alloy

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Journal of Magnesium and Alloys 2022年第1期10卷 66-87页

作者： Lei Ling Shu Cai qianqian Li Jiayue Sun Xiaogang Bao Guohua xu Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjinChina Department of Orthopedic Surgery Spine CenterChangzheng HospitalNaval Medical UniversityShanghaiChina

Magnesium(Mg) and its alloys have emerged as a favored candidate for bio-regenerative medical implants due to their superior biocompatibility, biodegradability and the elastic modulus close to that of human bone. Unfortunately, the rapid and uncontrollable degradation rate of Mg alloys in chloride-rich body microenvironments limits their clinical orthopedic applications. Recently, Calcium Phosphate(Ca-P)biomaterials, especially Hydroxyapatite(HA), have been broadly applied in the surface functional modification of metal-based biomaterials attributed to their excellent bioactivity and biocompatibility. Hydrothermal modification of Ca-P coatings on Mg alloys has been extensively exploited by researchers for its significant superiorities in controlling coating structure and improving interfacial bonding strength for better osseointegration and corrosion resistance. This work focuses on the up-to-the-minute advances in Ca-P coatings on the surface of Mg and its alloys via hydrothermal methods, including the strategies and mechanisms of hydrothermal modification. Herein, we are inclined to share some feasible and attractive hydrothermal surface modification strategies. From the perspectives of hydrothermal manufacturing technique innovation and coating structure optimization, we evaluate how to foster the corrosion resistance, coating bonding strength, osseointegration and antibacterial properties of Mg alloys with Ca-P coatings synthesized by hydrothermal method. The challenges and future perspectives on the follow-up exploration of Mg alloys for orthopedic applications are also elaborately proposed.

关键词： Calcium phosphorus Magnesium alloy Coatings Hydrothermal methods Corrosion resistance Biological properties

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东周龙凤耳陶簋的分析与研究

南方文物 2022年第1期 173-186页

作者：徐倩倩山东省文物考古研究院

龙凤耳陶簋是春秋时期出现的仿铜陶礼器,沿用到战国时期。簋身为盆、盂或豆形,腹有对称的龙耳、凤耳,耳多形体较大、造型夸张,器身及耳有彩绘。山东地区出土较多,其他地区也有少量出土。本文在对此类陶器进行型式分析的基础上,总结其空... 详细信息

龙凤耳陶簋是春秋时期出现的仿铜陶礼器,沿用到战国时期。簋身为盆、盂或豆形,腹有对称的龙耳、凤耳,耳多形体较大、造型夸张,器身及耳有彩绘。山东地区出土较多,其他地区也有少量出土。本文在对此类陶器进行型式分析的基础上,总结其空间分布、器物组合等,发现此类仿铜陶礼器在滕国、鲁国、齐国都各有不同,透过不同区域的代表器型,可以窥及背后的文化属性。

关键词：龙耳陶簋凤耳陶簋

Application of Sturm Theorem in the Global Controllability of a Class of High Dimensional Polynomial Systems

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Journal of Systems Science & Complexity 2015年第5期28卷 1049-1057页

作者： xu xueli LI qianqian SUN Yimin Guangdong Province Key Laboratory of Computational Science School of Mathematics and Computational Science Sun Yat-Sen University

In this paper, the global controllability for a class of high dimensional polynomial systems has been investigated and a constructive algebraic criterion algorithm for their global controllability has been obtained. By the criterion algorithm, the global controllability can be determined in finite steps of arithmetic operations. The algorithm is imposed on the coefficients of the polynomials only and the analysis technique is based on Sturm Theorem in real algebraic geometry and its modern progress.Finally, the authors will give some examples to show the application of our results.

关键词： Global controllability high dimensional systems number of sign variations polynomial Sturm theorem.

Screening and identification of candidate Fusarium wilt-resistance genes from pumpkin

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Horticultural Plant Journal 2022年第5期8卷 583-592页

作者： Jun xu qianqian Xian Ke Wang Jingping Dong Chaoyang Zhang Shengli Du xuewen xu xuehao Chen School of Horticulture and Plant Protection Yangzhou UniversityYangzhouJiangsu 225009China Huai’an Key Laboratory for Agricultural Biotechnology Huaiyin Institute of Agricultural Sciences in Xuhuai Region of Jiangsu ProvinceHuai’anJiangsu 223001China State Key Laboratory of Vegetable Germplasm Innovation Tianjin 300192China

Pumpkin(Cucurbita moschata)has been widely used as cucumber(Cucumis sativus L.)rootstock to defend against Fusarium wilt(FW)and increase cucumber yields and profits.However,the resistance genes and mechanisms underlying the FW tolerance in pumpkin are poorly understood.Here we analyzed the transcriptome of pumpkin inoculated with the cucumber FW causal agent Fusarium oxysporum f.***.cucumerinum(Foc),and obtained 3152 and 4735 upregulated genes induced by Foc at 24h after Foc inoculation compared with at 0h and 24h non-inoculated control,respectively.Next,404 common differentially expressed genes(DEGs)were screened using the criterion log_(2) FPKM(fold change)≥2.In total,206 of 404 DEGs were predominantly expressed in roots,which is the first tissue that Foc contacts and invades.140 DEGs were selected and classified into four groups(pathogenesis resistance,secondary metabolism-related,transcription factor and signal binding)based on their functional descriptions.Then,29 genes having high expression levels were selected to investigate the expression patterns induced by a Foc inoculation.Among them,16 genes were significantly induced by Foc and showed high expression levels at various treatment time points.These candidate genes may act as positive regulators of FW resistance in pumpkin and provide effective resources for improving cucumber FW resistance through breeding programs.

关键词： Pumpkin Rootstock Transcriptome Fusarium wilt Resistance genes

Diagnostic value of combination of rapid on-site evaluation and radial endobronchial ultrasound for peripheral pulmonary infectious lesions

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Chinese Medical Journal 2022年第23期135卷 2869-2871页

作者： Min Li Jiaqi Cao Qian He Ming Zhang qianqian xu Wenya Su Chunlai Feng Department of Respiratory and Critical Care Medicine The Third Affiliated Hospital of Soochow UniversityChangzhouJiangsu 213003

Peripheral pulmonary lesions(PPLs)are surrounded by lung parenchyma and invisible under an endoscope.The detection rate of PPLs by routine bronchoscopy is low.Radial endobronchial ultrasound(R-EBUS)can overcome those limitations,as it can locate peripheral bronchial lesions through a characteristic ultrasound signal.Rapid on-site evaluation(ROSE)is a real-time rapid cytological interpretation technology accompanied by tissue sampling.ROSEis helpful in improving the diagnostic rate of R-EBUS for PPLs,especially lung cancer.[1]However,the utility of ROSE during R-EBUS for peripheral pulmonary infectious lesions(infectious PPLs)is unclear.This study aimed to analyze the diagnostic value and safety of R-EBUS combined with ROSE in infectious PPLs.The study was approved by the Ethics Committee of the Third Affiliated Hospital of Soochow University(No.2019-017).The informed consent form was signed by the patient or his or her authorized legal representative.

关键词： lesions routine legal