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Evaluation of the coordinated development of China’s forest resources-economy-environment system 被引量:1
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作者 Yaofei Liu Yue Zhang +1 位作者 Yan Xu Zhijie Guan 《Chinese Journal of Population,Resources and Environment》 2023年第4期249-256,共8页
Forests provide enormous ecological, economic, and social benefits, as such forest development should be ori‐ented toward resource-economy-environment harmonization. This paper constructs a comprehensive evalua‐tion... Forests provide enormous ecological, economic, and social benefits, as such forest development should be ori‐ented toward resource-economy-environment harmonization. This paper constructs a comprehensive evalua‐tion index system and uses the coupled coordination degree model to measure the coordinated development level of China’ s forest resources-economy-environment system. The results show that, across 2006‒2020, the level of coupled coordinated development of China’ s forest resources-economy-environment composite system fluctuates in an upward trend, thus gradually developing from an initial imbalance to a high degree of coordi‐nation;the level of coordinated development of each subsystem of the forest resources, economy, and environ‐ment also shows an upward trend. The factors influencing the coordinated development of the forest resource economy-environment system are, in order, the government’ s financial capacity, market environment, scien‐tific and technological innovation capacity, level of economic development, and strength of policy implemen‐tation. Therefore, this paper proposes some measures to improve the coordinated development. 展开更多
关键词 Resources-economy-environment system Coupling coordination model Entropy method Grey correlation
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Optimization of Ultrasonic Extraction Process of Polysaccharides from Polyporus umbellatus 被引量:1
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作者 Juanjuan DU Mengting LIU Fei LI 《Agricultural Biotechnology》 CAS 2015年第6期7-9,共3页
[ Objective] This study aimed to investigate the optimal conditions for ultrasonic extraction of polysaccharides from Polyporus umbeUatus, thus providing a reliable basis for the development and utilization of P. umbe... [ Objective] This study aimed to investigate the optimal conditions for ultrasonic extraction of polysaccharides from Polyporus umbeUatus, thus providing a reliable basis for the development and utilization of P. umbellatus. [ Method ] By single-factor experiment, the ultrasonic extraction process of polyperus pelysac- charides was optimized. [Result] The optimal conditions for ultrasonic extraction of polysaccharides from P. umbeUatus were: solid-liquid ratio 1:40 (g: ml), ex- traction duration 60 rain, extraction temperature 70 ℃, ultrasonic power 100 W. [ Conclusion] Compared with conventional water extraction method, ultrasonic ex- traction could significantly improve the content of polyporus polysaccharides with shorter extraction duration, lower solid-liquid ratio and lower extraction tempera- 展开更多
关键词 Polyporus umbellatus POLYSACCHARIDES Ultrasonic extraction Single-factor experiment
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Estimation of the embodied carbon in China's wood products trade using input–output methodology
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作者 Zhijie Guan Qiong Zhao Yan Xu 《Chinese Journal of Population,Resources and Environment》 2020年第1期1-8,共8页
This study calculates the embodied carbon in imports,exports,net exports,and the processing trade of China's wood product sector between 2001 and 2016 using a non-competitive input-output(I-O)model.The results dem... This study calculates the embodied carbon in imports,exports,net exports,and the processing trade of China's wood product sector between 2001 and 2016 using a non-competitive input-output(I-O)model.The results demonstrate that embodied carbon showed a decreasing trend between 2001 and 2016.Embodied carbon was lowest in wood furniture imports and highest in paper and paperboard imports.The embodied carbon in sawnwood and veneer sheet exports was the lowest and paper and paperboard exports was the highest.The embodied carbon in the processing trade of paper and paperboard was the highest.To reduce the embodied carbon in China's wood products,the government should promote technological transformation and upgrading and encourage the implementation of green technology innovation. 展开更多
关键词 Input-output model Wood products Processing trade IMPORT EXPORT Net export Embodied carbon Carbon emissions
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The social welfare effect of forest certification under environmental spillovers
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作者 Zhijie Guan Yue Zhang Yan Xu 《Chinese Journal of Population,Resources and Environment》 2022年第3期245-250,共6页
Forest certification has positive environmental spillovers.Considering environmental spillovers,this study ana‐lyzed the social welfare effects of forest certification using partial and general equilibrium methods.Th... Forest certification has positive environmental spillovers.Considering environmental spillovers,this study ana‐lyzed the social welfare effects of forest certification using partial and general equilibrium methods.The re‐sults of the partial equilibrium analysis showed that social welfare in producing countries tended to increase under the market expansion of certified forest products.The general equilibrium analysis results indicated that,in autarky,or economic independence,the production amount of certified forest products could increase.If conventional forest products are imported and certified forest products are exported,then the level of utility in free trade condition is greater than that in autarky.If conventional forest products are exported and certi‐fied forest products are imported,then the price of imported products must be compared with the price of the autarky domestic market to determine the utility level of free trade and autarky.If the price of certified prod‐ucts is less than the price at the time of autarky,then the total utility level increases;otherwise,it decreases.The social welfare effect of forest certification can be increased through expanding the market demand of cer‐tified products and giving these products subsidies in production and price incentives in importing. 展开更多
关键词 Environmental spillover Forest certification Partial equilibrium General equilibrium Social welfare
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Identification and characterization of a TLR13 gene homologue from Laodelphax striatellus involved in the immune response induced by rice stripe virus
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作者 ZHOU Xue HU Jia +5 位作者 FU Mei-li JIN Ping ZHANG Yun-ye XIANG Ying LI Yao MA Fei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期183-192,共10页
Toll-like receptors(TLRs) are the critical superfamily homologues that initiate sensing of the invasion of pathogens by the Toll pathway. As one of several intracellular nucleic acid-sensing TLRs, TLR13 is activated b... Toll-like receptors(TLRs) are the critical superfamily homologues that initiate sensing of the invasion of pathogens by the Toll pathway. As one of several intracellular nucleic acid-sensing TLRs, TLR13 is activated by an unmethylated motif present in the large ribosomal subunit of bacterial RNA. However, little attention has been paid to the function of TLR13 gene homologue from Laodelphax striatellus(designated as LsToll-13) in the immune response to rice stripe virus(RSV). Herein, LsToll-13 was cloned and characterized using RACE-PCR. Phylogenetic analysis showed that LsToll-13 was clustered with the TLR13 from six insects. Real-time PCR analysis demonstrated that the expression level of LsToll-13 was significantly reduced in L. striatellus with RSV infection compared with that in the naive strain. When the expression of LsToll-13 was significantly up-regulated at 6 h after bacterial infection, the expression of ribonucleoprotein(RNP) indicated that the RSV titer in the host insect was significantly suppressed. Upon knockdown of LsToll-13, using RNA interference(RNAi) in L. striatellus, the expression level of RNP was significantly increased with enhanced RSV accumulation, suggesting that LsToll-13 potentially protects L. striatellus from RSV infection. Taken together, our results indicated that LsToll-13 might be involved in the immune response of L. striatellus to RSV infection, and provided a new insight into further elucidating the molecular mechanisms of complex pathogen-host interactions and integrative pest management. 展开更多
关键词 Laodelphax striatellus RSV TLR13 RNAI antiviral immunity
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Organometallic perovskite single crystals grown on lattice-matched substrate for photodetection
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作者 Xin Wang Yuwei Li +8 位作者 Yubing Xu Yuzhu Pan Yao Wua Guanwen Li Wei Zhang Shuyi Ding Jing Chen Wei Lei Dewei Zhao 《Nano Materials Science》 CAS 2020年第3期292-296,共5页
In this work,we demonstrate that an organometallic perovskite(OP)single crystal for effective photodetection can be grown on a gold(Au)-decorated substrate using liquid phase epitaxy.The covered gold could both contro... In this work,we demonstrate that an organometallic perovskite(OP)single crystal for effective photodetection can be grown on a gold(Au)-decorated substrate using liquid phase epitaxy.The covered gold could both control the shape of the epitaxial layer and act as its electrodes.An MAPbCl3 single crystal and an MAPbBr1.5Cl1.5 single crystal were used as the substrate and the epitaxial layer,respectively.The device,with an Au-perovskite-Au structure,can be fully characterized.Due to the high-quality epitaxial layer,the maximum external quantum efficiency(EQE)value is over 60%under the voltage of20 V.In addition,the response speed can reach 200 and 500 ns(ns)rise and fall,respectively.Our work provides an effective and promising method to fabricate efficient perovskite-based photodetectors. 展开更多
关键词 Perovskite single crystals Liquid phase epitaxy Ultraviolet detection
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Defects of Traditional Marketing Model and New Consumer Experience Requirements in the Context of"New Retail"
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作者 Yuejin Zhang 《Journal of Finance Research》 2018年第3期82-86,共5页
With the concept of"new retail"and the rapid development of"new retail"format,the defects of traditional marketing models such as advertising marketing,direct marketing and e-commerce marketing are... With the concept of"new retail"and the rapid development of"new retail"format,the defects of traditional marketing models such as advertising marketing,direct marketing and e-commerce marketing are becoming more and more obvious,which has seriously hindered the further development of the consumer retail industry.At the same time,under the background of"new retail",the industry demand based on the improvement of consumer experience is increasingly characterized by consumer entertainment,consumer autonomy,consumer personalization,and consumer socialization,which provides ideas and reference for the construction of new marketing models in the consumer retail industry. 展开更多
关键词 NEW RETAIL MARKETING model CONSUMER experience
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Roughness Research of Center Profile Curve on Rock Fracture Surface Based on Statistical Method
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作者 Xuezai Pan Zhigang Feng +1 位作者 Guoxing Dai Hongguang Liu 《Geomaterials》 2013年第2期47-53,共7页
In order to research roughness of rock fracture surfaces whether to depend on scale effect, Brazil discs were fractured under tensile and compression stresses in Brazil split test with MTS (Mechanics Test Systems) and... In order to research roughness of rock fracture surfaces whether to depend on scale effect, Brazil discs were fractured under tensile and compression stresses in Brazil split test with MTS (Mechanics Test Systems) and a laser profilometer was used to scan rock fracture surfaces and coordinates datum of central profile were acquired. A figure of the central profile was plotted through the coordinates datum. A certain line segment length is regarded as a step length, which is called scale and the scale length is taken to connect pairs of closer peak points on the profile curve. The directional distribution of every scale’s normal vector is analyzed by statistics and normal hypothesis test. Finally, some statistics of sample degrees datum are compared with other ones and reach a conclusion that roughness of center profile curve depends on scale effect. The distribution of degrees more and more approximates normal distribution along with increase of scale. 展开更多
关键词 ROCK MECHANICS ROCK Fracture Surfaces NORMAL VECTOR STATISTICS NORMAL Distribution
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Estimating rainfall intensity based on surveillance audio and deep-learning
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作者 Meizhen Wang Mingzheng Chen +4 位作者 Ziran Wang Yuxuan Guo Yong Wu Wei Zhao Xuejun Liu 《Environmental Science and Ecotechnology》 SCIE 2024年第6期135-145,共11页
Rainfall data with high spatial and temporal resolutions are essential for urban hydrological modeling.Ubiquitous surveillance cameras can continuously record rainfall events through video and audio,so they have been ... Rainfall data with high spatial and temporal resolutions are essential for urban hydrological modeling.Ubiquitous surveillance cameras can continuously record rainfall events through video and audio,so they have been recognized as potential rain gauges to supplement professional rainfall observation networks.Since video-based rainfall estimation methods can be affected by variable backgrounds and lighting conditions,audio-based approaches could be a supplement without suffering from these conditions.However,most audio-based approaches focus on rainfall-level classification rather than rainfall intensity estimation.Here,we introduce a dataset named Surveillance Audio Rainfall Intensity Dataset(SARID)and a deep learning model for estimating rainfall intensity.First,we created the dataset through audio of six real-world rainfall events.This dataset's audio recordings are segmented into 12,066 pieces and annotated with rainfall intensity and environmental information,such as underlying surfaces,temperature,humidity,and wind.Then,we developed a deep learning-based baseline using Mel-Frequency Cepstral Coefficients(MFCC)and Transformer architecture to estimate rainfall intensity from surveillance audio.Validated from ground truth data,our baseline achieves a root mean absolute error of 0.88 mm h^(-1) and a coefficient of correlation of 0.765.Our findings demonstrate the potential of surveillance audio-based models as practical and effective tools for rainfall observation systems,initiating a new chapter in rainfall intensity estimation.It offers a novel data source for high-resolution hydrological sensing and contributes to the broader landscape of urban sensing,emergency response,and resilience. 展开更多
关键词 Surveillance audio Rainfall intensity DATASET Regression Deep learning
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The Liouville Type Theorem for a System of Nonlinear Integral Equations on Exterior Domain
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作者 YIN Rong ZHANG Jihui SHANG Xudong 《Journal of Partial Differential Equations》 CSCD 2019年第3期191-206,共16页
In this paper we are concerned with a system of nonlinear integral equations on the exterior domain under the su让able boundary conditions.Through the method of moving planes in integral forms which has some innovativ... In this paper we are concerned with a system of nonlinear integral equations on the exterior domain under the su让able boundary conditions.Through the method of moving planes in integral forms which has some innovative ideas we obtain that the exterior domain is radial symmetry and a pair of positive solutions of the system is radial symmetry and monotone non-decreasing.Consequently,we can obtain the corresponding Liouville type theorem about the solutions. 展开更多
关键词 SYSTEM of integral equations EXTERIOR domain SYMMETRY MONOTONICITY LIOUVILLE type THEOREM
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