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“地理环境制约论”的提出与文学地理学研究——以中国民间文学作品的产生为例 被引量:7
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作者 邹建军 《歌海》 2021年第3期8-14,共7页
"地理环境决定论"是由孟德斯鸠开始,历经许多西方学者反复论证才发展起来的一种文化地理学理论,认为世界上所有的文化(包括文学和艺术)的起源、产生、形成和发展,都是由特定的地理环境所决定的。改革开放以后,许多中国学者对&... "地理环境决定论"是由孟德斯鸠开始,历经许多西方学者反复论证才发展起来的一种文化地理学理论,认为世界上所有的文化(包括文学和艺术)的起源、产生、形成和发展,都是由特定的地理环境所决定的。改革开放以后,许多中国学者对"地理环境决定论"展开研究,为中国文学地理学的发展提供了理论支持。在"地理环境决定论"的基础上,以中国民间文学的部分作品为例进行讨论,提出"地理环境制约论",丰富中国的文学地理学批评理论,有利于推动中国文学地理学的进一步发展。 展开更多
关键词 “地理环境决定论” “反地理环境决定论” “地理环境制约论” 文学地理学
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Microenvironment and electronic state modulation of Pd nanoparticles within MOFs for enhancing low-temperature activity towards DCPD hydrogenation
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作者 Zhiyuan Liu Changan Wang +8 位作者 Ping Yang Wei Wang Hongyi Gao Guoqing An Siqi Liu Juan Chen Tingting Guo Xinmeng Xu Ge Wang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期112-122,共11页
Precise control of the local environment and electronic state of the guest is an important method of controlling catalytic activity and reaction pathways.In this paper,guest Pd NPs were introduced into a series of hos... Precise control of the local environment and electronic state of the guest is an important method of controlling catalytic activity and reaction pathways.In this paper,guest Pd NPs were introduced into a series of host UiO-67 MOFs with different functional ligands and metal nodes,the microenvironment and local electronic structure of Pd is modulated by introducing bipyridine groups and changing metal nodes(Ce6O6 or Zr6O6).The bipyridine groups not only promoted the dispersion Pd NPs,but also facilitated electron transfer between Pd and UiO-67 MOFs through the formation of Pd-N bridges.Compared with Zr6 clusters,the tunability and orbital hybridisation of the 4f electronic structure in the Ce6 clusters modulate the electronic structure of Pd through the construction of the Ce-O-Pd interfaces.The optimal catalyst Pd/UiO-67(Ce)-bpy presented excellent low-temperature activity towards dicyclopentadiene hydrogenation with a conversion of>99%and a selectivity of>99%(50℃,10 bar).The results show that the synergy of Ce-O-Pd and Pd-N promotes the formation of active Pdδ+,which not only enhances the adsorption of H2 and electron-rich C=C bonds,but also contributes to the reduction of proton migration distance and improves proton utilization efficiency.These results provide valuable insights for investigating the regulatory role of the host MOFs,the nature of host-guest interactions,and their correlation with catalytic performance. 展开更多
关键词 Interface regulation Pdδ+ MICROENVIRONMENT Electronic state HYDROGENATION
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Impact of cold indoor thermal environmental conditions on human thermal response 被引量:6
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作者 刘红 谭青 +2 位作者 李百战 谈美兰 马小磊 《Journal of Central South University》 SCIE EI CAS 2011年第4期1285-1292,共8页
To explore the thermal responses under the non-thermal equilibrium cold environmental conditions,a laboratory study was conducted in climate chamber.The local skin temperatures and thermal sensation of 20 subjects wer... To explore the thermal responses under the non-thermal equilibrium cold environmental conditions,a laboratory study was conducted in climate chamber.The local skin temperatures and thermal sensation of 20 subjects were recorded at 10 min intervals for 90 min under air temperatures of 7.4,9.1,11 and 15 °C.The results show that both local skin temperatures and mean skin temperature decrease not only with the drop of ambient air temperature but also with the exposure time.Local thermal sensation and overall the thermal sensation have the similar temperature-varying and time-varying characteristics.Predicted mean vote(PMV) model cannot correctly predict the thermal sensation under non-thermal equilibrium cold environment.The correlation between local thermal sensation and local skin temperatures shows that thermal sensation is closely related to skin temperature.Skin temperature is an effective indicator of thermal sensation.A linear relationship model between overall thermal sensation and mean skin temperature,considering both ambient temperature and exposure time,was established in the non-thermal equilibrium cold environment,which makes the evaluation of thermal sensation more objective. 展开更多
关键词 indoor thermal environment thermal comfort thermal sensation skin temperature human thermal response
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Sustainable Activated Carbons from Agricultural Residues Dedicated to Antibiotic Removal by Adsorption 被引量:3
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作者 Jonatan Torres-Pérez Claire Gérente Yves Andrès 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第3期524-529,共6页
The. objectives.of this study are to convert at laboratory s.cale agric.ultural residues into activated carbons (AC) with specific properties, to characterize them and to test them in adsorption reactor for tetracyc... The. objectives.of this study are to convert at laboratory s.cale agric.ultural residues into activated carbons (AC) with specific properties, to characterize them and to test them in adsorption reactor for tetracycline removal, a common antibiotic. Two new ACs were produced by direct activation with steam from beet pulp (BP-H2O) and peanut hu_lls (PH-H2O) in environmental friendly conditions BP-H2O and PH-H2Opresentcarbon content rangedcarbons with different intrinsic properties. 展开更多
关键词 activated carbon ADSORPTION antibiotic characterisation waste valorisation water treatment
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Palladium nanoparticles assembled on titanium nitride for enhanced electrochemical hydrodechlorination of 2,4-dichlorophenol in water 被引量:6
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作者 Wenyang Fu Kaifeng Wang +5 位作者 Xiaoshu Lv Hailu Fu Xingan Dong Ling Chen Xianming Zhang Guangming Jiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期693-700,共8页
We report a one‐pot surfactant‐free wet‐chemical reduction approach to the synthesis of palladium/titanium nitride(Pd/TiN)and Pd/carbon(Pd/C)composites,in which^5 nm Pd NPs were uniformly dispersed on TiN or C.In t... We report a one‐pot surfactant‐free wet‐chemical reduction approach to the synthesis of palladium/titanium nitride(Pd/TiN)and Pd/carbon(Pd/C)composites,in which^5 nm Pd NPs were uniformly dispersed on TiN or C.In terms of catalytic performance,Pd/TiN showed enhanced efficiency and stability compared with those of Pd/C and bare TiN in the electrocatalytic hydrodechlorination(EHDC)reaction of 2,4‐dichlorophenol(2,4‐DCP)in aqueous solution.The superior performance of Pd/TiN arises from the promotion effect of TiN.Strong metal‐support interactions modified the electronic structure of Pd,which optimized generation of H*ads and 2,4‐DCP adsorption/activation.The cathode potential plays a vital role in controlling the EHDC efficiency and the product distribution.A working potential of?0.80 V was shown to be optimal for achieving the highest EHDC efficiency and maximizing conversion of 2,4‐DCP to phenol(P).Our studies of the reaction pathway show that EHDC of 2,4‐DCP on Pd/TiN proceeded by 2,4‐DCP→p‐chlorophenol(p‐CP),o‐chlorophenol(o‐CP)→P;however,Pd/TiN presented little selectivity for cleavage of p‐C‐Cl vs o‐C‐Cl.This work presents a new approach to enhancing Pd performance towards EHDC through the effects of a support.The strategy demonstrated here could also be extended to design highly efficient catalysts for other hydrogenation reactions. 展开更多
关键词 HYDRODECHLORINATION ELECTROLYSIS PALLADIUM Titanium nitride Environmental remediation
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Synthesis of propylene glycol ethers from propylene oxide catalyzed by environmentally friendly ionic liquids 被引量:4
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作者 Cong Zhao Shengxin Chen +4 位作者 Ruirui Zhang Zihang Li Ruixia Liu Baozeng Ren Suojiang Zhang 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第5期879-889,共11页
A series of acetate ionic liquids were synthesized using a typical two‐step method.The ionic liquids were used as environmentally benign catalysts in the production of propylene glycol ethers from propylene oxide and... A series of acetate ionic liquids were synthesized using a typical two‐step method.The ionic liquids were used as environmentally benign catalysts in the production of propylene glycol ethers from propylene oxide and alcohols under mild conditions.The basic strengths of the ionic liquids were evaluated by determination of their Hammett functions,obtained using ultraviolet‐visible spectroscopy,and the relationship between their catalytic activities and basicities was established.The catalytic efficiencies of the ionic liquids were higher than that of the traditional basic catalyst NaOH.This can be attributed to the involvement of a novel reaction mechanism when these ionic liquids are used.A possible electrophilic‐nucleophilic dual activation mechanism was proposed and confirmed using electrospray ionization quadrupole time‐of‐flight mass spectrometry.In addition,the effects of significant reaction parameters such as concentration of catalyst,molar ratio of alcohol to propylene oxide,reaction temperature,and steric hindrance of the alcohol were investigated in detail. 展开更多
关键词 Ionic liquid Propylene glycol ether ETHERIFICATION Propylene oxide Basic strength Reaction mechanism Environmental friendly
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Numerical analysis of thermal distortion of the mirror in space-to-groundlaser communicationlinks 被引量:1
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作者 LI Xiao-feng ZHANG Bai-lei LIN Mi QI Li-mei 《Optoelectronics Letters》 EI 2005年第3期209-212,共4页
The thermal distortion of an optical reflector surface due to the changing sunlight in a space environment will cause shift and spreading of its reflected focus and thereby influence the performance of space-to-ground... The thermal distortion of an optical reflector surface due to the changing sunlight in a space environment will cause shift and spreading of its reflected focus and thereby influence the performance of space-to-ground laser communication links. Based on the characteristics of a low orbit satellite, the normal shift of a plan mirror caused by thermal distortion is analyzed with the software of the ANSYS of finite element analysis. A general expression of the transmitted beam from a distorted reflector surface and a counting formula for the shifts of the focus center before and after thermal distortion are deduced. The result of simulation shews that the magnitude order of the normal shift of the antenna mirror surface can be as high as tens of urad. The worse the mirror thermal distortion is, the larger the shift of the received focus center is. And the change of the shifts does not obey a linear rule. 展开更多
关键词 激光通信 数字分析 热传递 光学 空间环境
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Pretreatment of coking wastewater using anaerobic sequencing batch reactor (ASBR) 被引量:10
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作者 李冰 孙英兰 李玉瑛 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第11期1115-1123,共9页
A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical me... A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical methane potential (BMP)of the coking wastewater in the acclimated granular biomass was measured. At the same time, some fundamental technological factors, such as the filling time and the reacting time ratio (tf/tr), the mixing intensity and the intermittent mixing mode, that affect anaerobic pretreatment of coking wastewater with ASBR, were evaluated through orthogonal tests. The COD removal efficiency reached 38%~50% in the stable operation period with the organic loading rate of 0.37~0.54 kg COD/(m3.d) at the optimum conditions of tf/tr, the mixing intensity and the intermittent mixing mode. In addition, the biodegradability of coking wastewater distinctly increased after the pretreatment using ASBR. At the end of the experiment, the microorganism forms on the granulated sludge in the ASBR were observed using SEM (scanning electron microscope) and fluoroscope. The results showed that the dominant microorganism on the granular sludge was Methanosaeta instead of Methanosarcina dominated on the inoculated sludge. 展开更多
关键词 Anaerobic sequencing batch reactor (ASBR) Coking wastewater Anaerobic pre-treatment
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Importance of nutrition in inflammatory bowel disease 被引量:13
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作者 Alfredo José Lucendo Livia Cristina De Rezende 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第17期2081-2088,共8页
Inflammatory bowel disease (IBD) results from the interaction between an individual's immune response and precipitant environmental factors, which generatean anomalous chronic inflammatory response in thosewho are ... Inflammatory bowel disease (IBD) results from the interaction between an individual's immune response and precipitant environmental factors, which generatean anomalous chronic inflammatory response in thosewho are genetically predisposed. Various feeding practices have been implicated in the origin of IBD based on epidemiological observations in developed countries, but we do not have solid evidence for the etiological role played by specific food types. IBD is associated with frequent nutritional deficiencies, thepattern and severity of which depends on the extent,duration and activity of the inflammation. Nutritional support allows these deficiencies in calories, macro and micronutrients to be rectified. Enteral nutrition is also aprimary therapy for IBD, especially for Crohn's disease,as it allows the inflammatory activity to be controlled,kept in remission, and Drevents or delays the need forsurgery. Nutritional support is especially important in childhood IBD as an alternative to pharmacological treatment. This report discusses the complex relationship between diet and IBD. 展开更多
关键词 Nutritional support Inflammatory boweldisease Enteral diet Crohn's disease Ulcerative colitis
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Optimized two-level placement of test points for multi-objective air monitoring of the Three Gorges Reservoir area 被引量:1
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作者 肖东海 《Journal of Chongqing University》 CAS 2007年第4期231-237,共7页
To fit the complicated geographic conditions of the Three Gorges Reservoir area, a two-level multi-objective monitoring system was developed to monitor the atmosphere of the area. Statistical analysis of environmental... To fit the complicated geographic conditions of the Three Gorges Reservoir area, a two-level multi-objective monitoring system was developed to monitor the atmosphere of the area. Statistical analysis of environmental monitoring data and the macro control principle were employed to configure the upper layer. The lower layer was designed by the application of the thumb rule to a local terrain and specific point sources of pollution therein. The optimized two-level system comprises an upper layer of 16 monitoring stations distributed at places of diverse geographical, ecological, economical and social characteristics, and a lower layer of ]6 sub-machines at each monitoring station of the upper layer. This optimal outcome fits the complicated conditions of the Three Gorges Reservoir area, substantially cuts down the installation cost and the operation cost, and provides accurate monitoring data of atmosphere over the entire area with a high resolution. 展开更多
关键词 Three Gorges Reservoir area air monitoring two-level placement multi-objective air monitoring
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Design of a 6.25 Gbps backplane SerDes with adaptive decision feedback equalization 被引量:1
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作者 周明珠 Zhu +2 位作者 En Wang Zhigong 《High Technology Letters》 EI CAS 2009年第4期409-415,共7页
A 6.25 Gbps SerDes core used in the high signed based on the OIF-CEI-02.0 standard. To speed backplane communication receiver has been decounteract the serious Inter-Syrmbol-Interference (ISI), the core employed a h... A 6.25 Gbps SerDes core used in the high signed based on the OIF-CEI-02.0 standard. To speed backplane communication receiver has been decounteract the serious Inter-Syrmbol-Interference (ISI), the core employed a half-rate four-tap decision feedback equalizer (DFE). The equalizer used the Signsign least mean-squared (SS-LMS) algorithm to realize the coefficient adaptation. An automatic gain control (AGC) amplifier with the sign least mean-squared (S-LMS) algorithm has been used to compensate the transmission media loss. To recover the clock signal from the input data serial and provide for the DFE and AGC, a bang-bang clock recovery (BB-CR) is adopted. A third order phase loop loek (PLL) model was proposed to predict characteristics of the BB-CR. The core has been verified by behavioral modeling in MATLAB. The results indicate that the core can meet the specifications of the backplane receiver. The DFE recovered data over a 34" FR-4 backplane has a peak-to-peak jitter of 17 ps, a horizontal eye opening of 0.87 UI, and a vertical eye opening of 500 mVpp. 展开更多
关键词 Serializer/Desterilizer (SerDes) adaptive equalizer decision feedback equalization (DFE) automatic gain control (AGC) amplifier bang-bang clock recovery (BB-CR)
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Capsella bursa-pastoris extract as an eco-friendly inhibitor on the corrosion of Q235 carbon steels in 1 mol·L^(-1) hydrochloric acid 被引量:4
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作者 胡琴 邱于兵 +1 位作者 张国安 郭兴蓬 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第8期1408-1415,共8页
The corrosion inhibition effect of Capsella bursa-pastoris extracts(CBE) for Q235 carbon steels in 1 mol·L-1hydrochloric acid solution was studied using electrochemical methods, environmental scanning electron mi... The corrosion inhibition effect of Capsella bursa-pastoris extracts(CBE) for Q235 carbon steels in 1 mol·L-1hydrochloric acid solution was studied using electrochemical methods, environmental scanning electron microscopy(SEM) and Raman microscopy analysis. The polarization plots indicate that CBE serves as an effective, mixedtype inhibitor. Linear polarization resistance shows that increasing CBE concentration and temperature results in increased inhibition ef ficiency. The highest inhibition ef ficiency can reach 97% when adding 60 mg·L-1CBE,which is better than some reported plant extracts under the similar environment. The adsorption of CBE molecules is found to obey the Langmuir adsorption isotherm. Some thermodynamic and kinetic parameters for the adsorption process, such as the adsorption equilibrium constant(K), free energy of adsorption(ΔG ads), activation energy of corrosion reaction(E a) and the heat of adsorption(Q ads), are calculated and discussed. SEM and Raman microscopy analysis also demonstrate the formation of a CBE inhibition film on the metal surface. 展开更多
关键词 Biomaterial Corrosion inhibitor Electrochemical technique SEM Raman spectroscopy
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Immune response-based algorithm for optimization of dynamic environments
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作者 史旭华 钱锋 《Journal of Central South University》 SCIE EI CAS 2011年第5期1563-1571,共9页
A novel immune algorithm suitable for dynamic environments (AIDE) was proposed based on a biological immune response principle.The dynamic process of artificial immune response with operators such as immune cloning,mu... A novel immune algorithm suitable for dynamic environments (AIDE) was proposed based on a biological immune response principle.The dynamic process of artificial immune response with operators such as immune cloning,multi-scale variation and gradient-based diversity was modeled.Because the immune cloning operator was derived from a stimulation and suppression effect between antibodies and antigens,a sigmoid model that can clearly describe clonal proliferation was proposed.In addition,with the introduction of multiple populations and multi-scale variation,the algorithm can well maintain the population diversity during the dynamic searching process.Unlike traditional artificial immune algorithms,which require randomly generated cells added to the current population to explore its fitness landscape,AIDE uses a gradient-based diversity operator to speed up the optimization in the dynamic environments.Several reported algorithms were compared with AIDE by using Moving Peaks Benchmarks.Preliminary experiments show that AIDE can maintain high population diversity during the search process,simultaneously can speed up the optimization.Thus,AIDE is useful for the optimization of dynamic environments. 展开更多
关键词 dynamic optimization artificial immune algorithms immune response multi-scale variation
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Spontaneous combustion tendency of fresh and pre-oxidized sulfide ores 被引量:2
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作者 阳富强 吴超 李孜军 《Journal of Central South University》 SCIE EI CAS 2014年第2期715-719,共5页
Three representative sulfide ore samples were collected from typical metal mines,and their corresponding pre-oxidized products were obtained under nature environment.The thermal behaviors of each sample at heating rat... Three representative sulfide ore samples were collected from typical metal mines,and their corresponding pre-oxidized products were obtained under nature environment.The thermal behaviors of each sample at heating rates of 5,10,15 and 20 °C/min in air flow from ambient temperature to 800 °C were studied by simultaneous thermal analysis and the TG/DSC curves before and after the pre-oxidation were compared.By the peak temperature of DTG curves,the whole reaction process for each sample was divided into different stages,and the apparent activation energies were calculated by the Ozawa-Flynn-Wall method.The results show that the reaction process of each sample after pre-oxidation is more complex,with quicker reaction rates,fewer heat production quantities,and higher or lower ignition-points.The apparent activation energies decrease from 364.017-474.228 kJ/mol to 244.523- 333.161 kJ/mol.Therefore,sulfide ores are more susceptible to spontaneous combustion after the pre-oxidation. 展开更多
关键词 sulfide ores spontaneous combustion tendency apparent activation energy PRE-OXIDATION
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Reactor Network Synthesis for Waste Reduction Using Instantaneous Value of Environmental Index 被引量:2
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作者 陈启石 冯霄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期155-158,共4页
Waste reduction is gaining importance as the preferred means of pollution prevention. Reactor network synthesis is one of the key parts of chemical process synthesis. In this study, a geometric approach to reactor net... Waste reduction is gaining importance as the preferred means of pollution prevention. Reactor network synthesis is one of the key parts of chemical process synthesis. In this study, a geometric approach to reactor network synthesis for waste reduction is presented. The bases of the approach are potential environment impact (PEI) rate-law expression, PEI balance and the instantaneous value of environmental indexes. The instantaneous value can be derived using the PEI balance, PEI rate-law expression and the environmental indexes. The optimal reactor networks with the minimum generation of potential environment impact are geometrically derived by comparing with areas of the corresponding regions. From the case study involving complex reactions, the approach does not involve solving the complicated mathematical problem and can avoid the dimension limitation in the attainable region approach. 展开更多
关键词 instantaneous value of environmental indexes reactor network synthesis potential environmental impact waste reduction
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Effect of Air Velocity on Thermal Comfort under Thermal Environment Ramp Changing 被引量:1
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作者 嵇赟喆 涂光备 孙琳 《Transactions of Tianjin University》 EI CAS 2004年第4期291-296,共6页
Set points of the indoor air temperature and relative humidity in short-term staying location were studied. In this condition, the thermal reaction of human body varied with the ramp changes of the environmental therm... Set points of the indoor air temperature and relative humidity in short-term staying location were studied. In this condition, the thermal reaction of human body varied with the ramp changes of the environmental thermal parameters.The change rules of about 60 subjects′ thermal reaction to the ramp change of environment were surveyed, and the effect of air movement on the thermal reaction during transient condition was considered by using a questionnaire. With the experimental results and research findings under stable condition, a way to set environmental parameters of short-time staying location was recommended. 展开更多
关键词 transient environment ramp change thermal comfort air velocity
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A New Method of Profiling Remote-Sensing Reflectance of Coastal Waters
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作者 李铜基 陈清莲 +1 位作者 汪小勇 杨安安 《Marine Science Bulletin》 CAS 2005年第1期37-44,共8页
The profiling method is the first method to select in measuring the remote-sensing reflectance. In the light of the characteristics of China’s coastal waters, we develop a new method to compensate the environment’s ... The profiling method is the first method to select in measuring the remote-sensing reflectance. In the light of the characteristics of China’s coastal waters, we develop a new method to compensate the environment’s effects with the downwelling (λ)rsi r radiance’s profile and to estimate the underwater remote-sensing reflectance r. (λ)rsT he result indicates that the relative deviation of repetitious r in one station is around 10 %. 展开更多
关键词 profiling method remote-sensing reflectance METHOD
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Spatial Distribution and Environmental Determinants of Denitrification Enzyme Activity in Reed-Dominated Raised Fields 被引量:2
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作者 LAN Yan CUI Baoshan +3 位作者 HAN Zhen LI Xia LI Fengju ZHANG Yongtao 《Chinese Geographical Science》 SCIE CSCD 2015年第4期438-450,共13页
Denitrification is an important process of nitrogen removal in lake ecosystems.However,the importance of denitrification across the entire soil-depth gradients including subsurface layers remains poorly understood.Thi... Denitrification is an important process of nitrogen removal in lake ecosystems.However,the importance of denitrification across the entire soil-depth gradients including subsurface layers remains poorly understood.This study aims to determine the spatial pattern of soil denitrification enzyme activity(DEA) and its environmental determinants across the entire soil depth gradients in the raised fields in Baiyang Lake,North China.In two different zones of the raised fields(i.e.,water boundary vs.main body of the raised fields),the soil samples from 1.0 m to 1.1 m depth were collected,and the DEA and following environmental determinants were quantified:soil moisture,p H,total nitrogen(TN),ammonia nitrogen(NH4+-N),nitrate nitrogen(NO3–-N),total organic carbon(TOC),and rhizome biomass of Phragmites australis.The results showed that the soil DEA and environmental factors had a striking zonal distribution across the entire soil depth gradients.The soil DEA reached two peak values in the upper and middle soil layers,indicating that denitrification are important in both topsoil and subsurface of the raised fields.The correlation analysis showed that the DEA is negatively correlated with the soil depth(p < 0.05).However,this phenomenon did not occur in the distance to the water edge,except in the upper layers(from 0.2 m to 0.7 m) of the boundary zone of the raised fields.In the main body of the raised fields,the DEA level remained high;however,it showed no significant relationship with the distance to the water edge.The linear regression analysis showed significant positive correlation of the DEA with the soil TN,NO3–-N,NH4+-N,and TOC;whereas it showed negative correlation with soil p H.No significant correlations with soil moisture and temperature were observed.A positive correlation was also found between the DEA and rhizome biomass of P.australis. 展开更多
关键词 denitrification enzyme activity(DEA) nitrate removal raised fields Baiyang Lake rhizomes
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Development of Reaction Process with the Consideration of Environmental Impact Minimization
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作者 陈启石 冯霄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期611-615,共5页
A methodology is presented to identify environmental impact minimization alternatives for reaction processes and assess their environmental performance. The potential environmental impact (PEI) scheme can be used to v... A methodology is presented to identify environmental impact minimization alternatives for reaction processes and assess their environmental performance. The potential environmental impact (PEI) scheme can be used to visibly display the transformation relationships among different types of PEI, identify the sources of environmental impacts, and propose alternatives for eliminating or minimizing the impacts. To evaluate the environmental performance of the alternatives effectively, some new indices, such as PEI input rate of non-products, PEI output rate of non-products per profit and the PEI conversion efficiency are proposed. Finally, the application of the methodology is illustrated using an industrial case study. 展开更多
关键词 potential environmental impact scheme development of chemical process environmental protection
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Research on Resource Development Countermeasures and Environmental Governance of Cruise Tourism Enterprises in China
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作者 MENG jizhi 《International English Education Research》 2018年第2期43-45,共3页
The development of tourism resources aims to process tourism raw materials into direct-consumption tourism products. The essence of this behavior is innovation. The theory of innovation in economics, management, socio... The development of tourism resources aims to process tourism raw materials into direct-consumption tourism products. The essence of this behavior is innovation. The theory of innovation in economics, management, sociology, oriental management, and related disciplines provided methodology for the development of tourism resources and pointed out the direction. With the development of tourism, the cruise economy has grown and the urban economy has been rapidly developed and improved. However, while cruise tourism brings economic benefits, the discharge of various waste water and exhaust gas from cruise ships of major cruise companies also brings about some environmental pollution problems. Therefore, the environmental protection issue of cruise tourism companies is a sustainable development issue. Persisting in sustainable development strategy, we attach importance to the environmental governance of the cruise tourism industry. 展开更多
关键词 cruise ship enterprise resource development sustainable development environmental governance
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