Kirsten rat sarcoma viral oncogene homolog(KRAS)-phosphodiesterase-delta(PDEδ)is a promising target for antitumor drug discovery.Herein,highly efficient and environmentally sensitive fluorescent probes of PDEδ(DS-Pr...Kirsten rat sarcoma viral oncogene homolog(KRAS)-phosphodiesterase-delta(PDEδ)is a promising target for antitumor drug discovery.Herein,highly efficient and environmentally sensitive fluorescent probes of PDEδ(DS-Probes)were rationally designed.As compared with the reported PDEδprobes,DS-Probes showed higher binding affinity and selectivity,which were able to conveniently and efficiently label PDEδin live cells as well as tumor tissues.Therefore,these fluorescent probes are expected to facilitate PDEδ-based mechanism elucidation,drug discovery and pathologic diagnosis.展开更多
A simply synthesized 4-aminonaphthalimide derivative 1 expresses both polarity and viscosity sensitive fluorescence spectra,indicating its potential usage as an environmentally sensitive fluorescence probe. By compari...A simply synthesized 4-aminonaphthalimide derivative 1 expresses both polarity and viscosity sensitive fluorescence spectra,indicating its potential usage as an environmentally sensitive fluorescence probe. By comparing the fluorescence behavior of 1 with that of a known 4-aminonaphthalimide derivative 2,it was found that the substitution of the 4-amino group has profound influence on the environmentally sensitive fluorescence properties of 4-aminonaphthalimide.展开更多
By analyzing the influence of pollution factors in each process on the environmentally sensitive area in construction and operation of oil and gas infrastructure,main problems were obtained:delimitation and implementa...By analyzing the influence of pollution factors in each process on the environmentally sensitive area in construction and operation of oil and gas infrastructure,main problems were obtained:delimitation and implementation of three control lines in land space planning,relevant environmental protection laws and regulations not perfect and specific,delimitation of environmentally sensitive area lack of sufficient demonstration,"conditional permission to pass"not be raised to an explicit provision,urban energy corridor planning not fully implement the concept of environmental protection,and the idea of adjacent spatial planning not be implemented yet.Moreover,it put forward countermeasures and suggestions for the construction department of oil and gas infrastructure.展开更多
The availability of better economic possibilities and well-connected transportation networks has attracted people to migrate to peri-urban and rural neighbourhoods,changing the landscape of regions outside the city an...The availability of better economic possibilities and well-connected transportation networks has attracted people to migrate to peri-urban and rural neighbourhoods,changing the landscape of regions outside the city and fostering the growth of physical infrastructure.Using multi-temporal satellite images,the dynamics of Land Use/Land Cover(LULC)changes,the impact of urban growth on LULC changes,and regional environmental implications were investigated in the peri-urban and rural neighbourhoods of Durgapur Municipal Corporation in India.The study used different case studies to highlight the study area’s heterogeneity,as the phenomenon of change is not consistent.Landsat TM and OLI-TIRS satellite images in 1991,2001,2011,and 2021 were used to analyse the changes in LULC types.We used the relative deviation(RD),annual change intensity(ACI),uniform intensity(UI)to show the dynamicity of LULC types(agriculture land;built-up land;fallow land;vegetated land;mining area;and water bodies)during 1991-2021.This study also applied the Decision-Making Trial and Evaluation Laboratory(DEMATEL)to measure environmental sensitivity zones and find out the causes of LULC changes.According to LULC statistics,agriculture land,built-up land,and mining area increased by 51.7,95.46,and 24.79 km^(2),respectively,from 1991 to 2021.The results also suggested that built-up land and mining area had the greatest land surface temperature(LST),whereas water bodies and vegetated land showed the lowest LST.Moreover,this study looked at the relationships among LST,spectral indices(Normalized Differenced Built-up Index(NDBI),Normalized Difference Vegetation Index(NDVI),and Normalized Difference Water Index(NDWI)),and environmental sensitivity.The results showed that all of the spectral indices have the strongest association with LST,indicating that built-up land had a far stronger influence on the LST.The spectral indices indicated that the decreasing trends of vegetated land and water bodies were 4.26 and 0.43 km^(2)/a,respectively,during 1991-2021.In summary,this study can help the policy-makers to predict the increasing rate of temperature and the causes for the temperature increase with the rapid expansion of built-up land,thus making effective peri-urban planning decisions.展开更多
To cooperate with the five ministries and commissions of the state to carry out joint investigation on the environmentally sensitive areas involved in oil and gas exploration and development,for the problems found in ...To cooperate with the five ministries and commissions of the state to carry out joint investigation on the environmentally sensitive areas involved in oil and gas exploration and development,for the problems found in survey,containing complex type and numerous amount of ecologically sensitive space and ecological red line involved in oil and gas field enterprises,scientific nature of delimitation,lack of strong support of laws and regulations for forced withdrawal of oil and gas production facilities in these areas,some countermeasures and suggestions were proposed,such as further evaluating and combing scope and functional zoning of existing environmentally sensitive areas and ecological red lines,treating differently,enhancing pertinence of prohibition in ecologically sensitive regions,declining blindness of the withdrawal of oil and gas facilities in environmentally sensitive areas,strengthening seriousness of approval of exploration and mining rights of oil and gas resources,and establishing strategic reserve exploration and hierarchical development mechanism. Moreover,oil and gas field enterprises should integrate more efforts to ① accelerate to find out the current situation of environmental quality,② adhere to developing in protection,and protecting in development,③ increase attention and participation strengthen of providing technical support for national oil and gas exploration and development strategy evaluation,④ accelerate communication and docking with local governments on the ecological red line,⑤ actively strive to be included in the positive list management of local governments,⑥ accelerate to establish and perfect primary database of oil and gas production and facilities construction,and ⑦ document management information system of the ecological red line.展开更多
Urban eco-environmental degradation is becoming inevitable due to the extensive urbanization, popula- tion growth, and socioeconomic development in China. One of the traffic arteries in Shenzhen is an urban expressway...Urban eco-environmental degradation is becoming inevitable due to the extensive urbanization, popula- tion growth, and socioeconomic development in China. One of the traffic arteries in Shenzhen is an urban expressway that is under construction and that runs across environmentally sensitive areas (ESAs). The environmental pollution from urban expressways is critical, due to the characteristics of expressways such as high runoff coefficients, considerable contaminant accumulation, and complex pollutant ingredi- ents. ESAs are vulnerable to anthropogenic disturbances and hence should be given special attention. In order to evaluate the environmental sensitivity along this urban expressway and minimize the influences of the ongoing road construction and future operation on the surrounding ecosystem, the environmental sensitivity of the relevant area was evaluated based on the application of a geographic information sys- tem (GIS). A final ESA map was classified into four environmental sensitivity levels; this classification indicates that a large proportion of the expressway passes through areas of high sensitivity, representing 11.93 km or 52.3% of the total expressway, and more than 90% of the total expressway passes through ESAs. This study provides beneficial information for optimal layout schemes of initial rainfall runofftreatment facilities developed from low-impact development (LID) techniques in order to minimize the impact of polluted road runoff on the surrounding ecological environment.展开更多
This paper examines the cost of environmental regulation and the environmental total factor productivity (TFP) with directional distance function and the Malmquist-Luenberger (ALL) index respectively, using inputs...This paper examines the cost of environmental regulation and the environmental total factor productivity (TFP) with directional distance function and the Malmquist-Luenberger (ALL) index respectively, using inputs and output data of 36 two-digit industries over the period 1998- 2010. It finds that Chinese industries incur a relatively high environmental regulatory cost and that China has paid a high price fulfilling its promise to emissions mitigation. A comparison between conventional and environmental TFP shows that the two indicators for all industries declined on average, but a hypothesis test reveals insignificant difference between the two. In addition, the rise in environmental TFP is mainly due to technological progress, which is consistent with findings of many researches; analysis demonstrates signs of absolute convergence of environmental TFP.展开更多
According to sensitivity to environment, rice varieties can be classified into a strong environmentally sensitive variety, a weak environmentally sensitive variety and an environmentally insensitive variety. The gener...According to sensitivity to environment, rice varieties can be classified into a strong environmentally sensitive variety, a weak environmentally sensitive variety and an environmentally insensitive variety. The general method that was used to evaluate the environmental sensitivity (ES) of rice variety was put forward in this paper. ESs of varieties were evaluated as follows:(1) ES of indica-japonica hybird rice was more sensitive than that of japonica rice. (2)The order of ESs of japonica type varieties was medium-maturing late japonica variety > early-maturing late japonica variety > late-maturing medium japonica variety > medium-maturing medium japonica variety. (3)There was a significant difference in ESs among varieties of the same japonica type rice, too. Some problems, such as the principles of rather late-maturing rice planted northward, were also discussed at the end of this paper.展开更多
[Objective] This study aimed to assess the vulnerability of ecological environment in Hebei Province.[Method] Based on ArcGIS,by using the dominant factor and maximum limits factor method,we established the sensitivit...[Objective] This study aimed to assess the vulnerability of ecological environment in Hebei Province.[Method] Based on ArcGIS,by using the dominant factor and maximum limits factor method,we established the sensitivity-reality indicator system and assessment model of the eco-environment vulnerability in Hebei Province to quantitatively evaluate its eco-environment vulnerability,and analyzed its spatial distribution.[Result] The status quo of environmental degradation was inconsistent with the sensitivity of eco-environment in Hebei Province.The area of severely vulnerable region accounted for only 4.1% of total area in Hebei Province,mainly distributed in nine counties or districts of Baxia region,Zhangjiakou,northwestern Hebei,which was covered with mountains and basins,showing bands,which resulted from the vulnerability of soil erosion and land desertification.In addition,the moderately vulnerable region made up 38.4%,having the largest proportion,and mainly distributed in the mountain and basin region in northwestern Hebei,Yanshan Mountain and the most regions of Taihang Mountain,due to the vulnerability of soil erosion.At the same time,there were also large patches of moderately vulnerable region in Bashang and Baxia of Zhangjiakou,owning to the vulnerability of land desertification.Besides,most plains were mildly vulnerable and slightly vulnerable regions,and their areas accounted for 25.1% and 32.4% respectively of total area.[Conclusion] The research could provide scientific references for safeguarding the ecological security and main functional district planing of Hebei Province.展开更多
Land degradation has a major impact on environmental and socio-economic sustainability. Scientific methods are necessary to monitor the risk of land degradation. In this study, the environmental sensitive area index(E...Land degradation has a major impact on environmental and socio-economic sustainability. Scientific methods are necessary to monitor the risk of land degradation. In this study, the environmental sensitive area index(ESAI) was utilized to assess land degradation sensitivity and convergence analysis in Korla, a typical oasis city in Xinjiang of China, which is located on the northeast border of the Tarim Basin. A total of 18 indicators depicting soil, climate, vegetation, and management qualities were used to illustrate spatial-temporal patterns of land degradation sensitivity from 1994 to 2018. We investigated the causes of spatial convergence and divergence based on the Ordinary Least Squares(OLS) and Geographically Weighted Regression(GWR) models. The results show that the branch of the Tianshan Mountains and oasis plain had a low sensitivity to land degradation, while the Tarim Basin had a high risk of land degradation. More than two-thirds of the study area can be categorized as "critical" sensitivity classes. The largest percentage(32.6%) of fragile classes was observed for 2006. There was no significant change in insensitive or low-sensitivity areas, which accounted for less than 0.4% of the entire observation period. The ESAI of the four time periods(1994–1998, 1998–2006, 2006–2010, and 2010–2018) formed a series of convergence patterns. The convergence patterns of 1994–1998 and 1998–2006 can be explained by the government's efforts to "Returning Farmland to Forests" and other governance projects. In 2006–2010, the construction of afforested work intensified, but industrial development and human activities affected the convergence pattern. The pattern of convergence in most regions between 2010 and 2018 can be attributed to the government's implementation of a series of key ecological protection projects, which led to a decrease in sensitivity to land degradation. The results of this study altogether suggest that the ESAI convergence analysis is an effective early warning method for land degradation sensitivity.展开更多
Poly(N,N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by gamma-irradiation showed obvious temperature-sensitivity in a temperature range of 38-40degreesC and pH-sensitivity at pH=2.5. They also sho...Poly(N,N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by gamma-irradiation showed obvious temperature-sensitivity in a temperature range of 38-40degreesC and pH-sensitivity at pH=2.5. They also showed electric response behavior although it was not typical. The hydrogels were used in controlled release at different pH, temperature, and electric voltage. The release rates of methylene blue (MB) from the gels at 52degreesC and pH=1.24 were faster than those at 20degreesC and pH=10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that without electric field.展开更多
We here present a Förster resonance energy transfer(FRET)-based and environment-sensitive fluorescent probe VG-1 for vicinal-dithiol-containing proteins(VDPS).VG-1 uniquely contalns two sites sensitive to the pro...We here present a Förster resonance energy transfer(FRET)-based and environment-sensitive fluorescent probe VG-1 for vicinal-dithiol-containing proteins(VDPS).VG-1 uniquely contalns two sites sensitive to the protein environment(SPE)thus it shows weak fluorescence in both blue and green channels(a low FRET efficiency)in solution.After specifically binding with VDPs,its fuorescence in the green channel increases,while that in the blue channel disappears,achieving the specific detection of VDPs.The obvioussignal changes in fluorescence may be attributed to that the increased rigidity of the molecular skeletons causes the enhanced FRET eficiency,The probe also achleved the cell super-resolution imaging of VDPs and the confocal imaging of VDPs in zebrafish.展开更多
This paper develops an economic production quantity(EPQ)model for a singlemanufacturer multi-retailer(SMMR)production and reworking system with green and environmental sensitive customer demand.The minimum cost of the...This paper develops an economic production quantity(EPQ)model for a singlemanufacturer multi-retailer(SMMR)production and reworking system with green and environmental sensitive customer demand.The minimum cost of the manufacturer has obtained under carbon emissions(CE)policies and discrete ordering cost reduction.The model is used to optimize the total number of shipments,greening investment level,environmental measure,and lot size for productions and rework.This research work determines that the manufacturer’s and retailer’s profits will be increased after considering the environmental and green dependent demand of customers.Further,the development of green and environmental demand is proposed to minimize the CE and maximize the demand for the customers.In the existing literature,no discrete investment is developed for reducing the cost of ordering for the retailer/buyer.However,in this paper,we have introduced it.We provide numerical examples to explain the models and determine the significance of model parameters.展开更多
17 samples were collected from aeolian and lacustrine profiles within the environment sensitive zone of the Loess Plateau, and an experimental method was established which is suitable for pollen extraction from aeolia...17 samples were collected from aeolian and lacustrine profiles within the environment sensitive zone of the Loess Plateau, and an experimental method was established which is suitable for pollen extraction from aeolian sediment. A comparative study of pollen dating was carried out using the accelerator mass spectrometry (AMS)14C dating of known age samples, and then an experiment with the pollen concentrates was performed. The results indicate that pollen that has been deposited simultaneously with sediment in a stable environment can provide reliable ages. This technique will provide a way of improving the chronological framework for the Loess Plateau since the late Pleistocene. TheI4c dating was combined with field investigations, and from the geological record within this zone, evidence was extracted of four major monsoon precipitation changes during the transition from the late Pleistocene to Holocene.展开更多
Energy transfer and electron transfer are both fundamental mechanisms enabling numerous functional materials and applications.While most materials systems employ either energy transfer or electron transfer,the combine...Energy transfer and electron transfer are both fundamental mechanisms enabling numerous functional materials and applications.While most materials systems employ either energy transfer or electron transfer,the combined effect of energy and electron transfer processes in a single donor/acceptor system remains largely unexplored.Herein,we demonstrated the energy transfer followed by electron transfer(ETET)process in a molecular dyad TPE-NBD.Due to energy transfer,the fluorescence of TPE-NBD was greatly enhanced in non-polar solvents.In contrast,polar solvents activated subsequent electron transfer and markedly quenched the emission of TPE-NBD.Consequently,ETET endows TPE-NBD with significant polarity sensitivities.We expect that employing ETET could generate many functional materials with unprecedented properties,i.e.,for single laser powered multicolor fluorescence imaging and sensing.展开更多
基金supported by the National Key Research and Development Program of China(No.2020YFA0509200 to C.Sheng)National Natural Science Foundation of China(Nos.81903436 to Y.Li,82204211 to W.Wang and 22077138 to S.Wu)Shanghai Rising-Star Program(No.22QA1411300 to S.Wu).
文摘Kirsten rat sarcoma viral oncogene homolog(KRAS)-phosphodiesterase-delta(PDEδ)is a promising target for antitumor drug discovery.Herein,highly efficient and environmentally sensitive fluorescent probes of PDEδ(DS-Probes)were rationally designed.As compared with the reported PDEδprobes,DS-Probes showed higher binding affinity and selectivity,which were able to conveniently and efficiently label PDEδin live cells as well as tumor tissues.Therefore,these fluorescent probes are expected to facilitate PDEδ-based mechanism elucidation,drug discovery and pathologic diagnosis.
基金the National Science & Technology Pillar Program of China(No.2011BAE31B01)
文摘A simply synthesized 4-aminonaphthalimide derivative 1 expresses both polarity and viscosity sensitive fluorescence spectra,indicating its potential usage as an environmentally sensitive fluorescence probe. By comparing the fluorescence behavior of 1 with that of a known 4-aminonaphthalimide derivative 2,it was found that the substitution of the 4-amino group has profound influence on the environmentally sensitive fluorescence properties of 4-aminonaphthalimide.
文摘By analyzing the influence of pollution factors in each process on the environmentally sensitive area in construction and operation of oil and gas infrastructure,main problems were obtained:delimitation and implementation of three control lines in land space planning,relevant environmental protection laws and regulations not perfect and specific,delimitation of environmentally sensitive area lack of sufficient demonstration,"conditional permission to pass"not be raised to an explicit provision,urban energy corridor planning not fully implement the concept of environmental protection,and the idea of adjacent spatial planning not be implemented yet.Moreover,it put forward countermeasures and suggestions for the construction department of oil and gas infrastructure.
文摘The availability of better economic possibilities and well-connected transportation networks has attracted people to migrate to peri-urban and rural neighbourhoods,changing the landscape of regions outside the city and fostering the growth of physical infrastructure.Using multi-temporal satellite images,the dynamics of Land Use/Land Cover(LULC)changes,the impact of urban growth on LULC changes,and regional environmental implications were investigated in the peri-urban and rural neighbourhoods of Durgapur Municipal Corporation in India.The study used different case studies to highlight the study area’s heterogeneity,as the phenomenon of change is not consistent.Landsat TM and OLI-TIRS satellite images in 1991,2001,2011,and 2021 were used to analyse the changes in LULC types.We used the relative deviation(RD),annual change intensity(ACI),uniform intensity(UI)to show the dynamicity of LULC types(agriculture land;built-up land;fallow land;vegetated land;mining area;and water bodies)during 1991-2021.This study also applied the Decision-Making Trial and Evaluation Laboratory(DEMATEL)to measure environmental sensitivity zones and find out the causes of LULC changes.According to LULC statistics,agriculture land,built-up land,and mining area increased by 51.7,95.46,and 24.79 km^(2),respectively,from 1991 to 2021.The results also suggested that built-up land and mining area had the greatest land surface temperature(LST),whereas water bodies and vegetated land showed the lowest LST.Moreover,this study looked at the relationships among LST,spectral indices(Normalized Differenced Built-up Index(NDBI),Normalized Difference Vegetation Index(NDVI),and Normalized Difference Water Index(NDWI)),and environmental sensitivity.The results showed that all of the spectral indices have the strongest association with LST,indicating that built-up land had a far stronger influence on the LST.The spectral indices indicated that the decreasing trends of vegetated land and water bodies were 4.26 and 0.43 km^(2)/a,respectively,during 1991-2021.In summary,this study can help the policy-makers to predict the increasing rate of temperature and the causes for the temperature increase with the rapid expansion of built-up land,thus making effective peri-urban planning decisions.
文摘To cooperate with the five ministries and commissions of the state to carry out joint investigation on the environmentally sensitive areas involved in oil and gas exploration and development,for the problems found in survey,containing complex type and numerous amount of ecologically sensitive space and ecological red line involved in oil and gas field enterprises,scientific nature of delimitation,lack of strong support of laws and regulations for forced withdrawal of oil and gas production facilities in these areas,some countermeasures and suggestions were proposed,such as further evaluating and combing scope and functional zoning of existing environmentally sensitive areas and ecological red lines,treating differently,enhancing pertinence of prohibition in ecologically sensitive regions,declining blindness of the withdrawal of oil and gas facilities in environmentally sensitive areas,strengthening seriousness of approval of exploration and mining rights of oil and gas resources,and establishing strategic reserve exploration and hierarchical development mechanism. Moreover,oil and gas field enterprises should integrate more efforts to ① accelerate to find out the current situation of environmental quality,② adhere to developing in protection,and protecting in development,③ increase attention and participation strengthen of providing technical support for national oil and gas exploration and development strategy evaluation,④ accelerate communication and docking with local governments on the ecological red line,⑤ actively strive to be included in the positive list management of local governments,⑥ accelerate to establish and perfect primary database of oil and gas production and facilities construction,and ⑦ document management information system of the ecological red line.
文摘Urban eco-environmental degradation is becoming inevitable due to the extensive urbanization, popula- tion growth, and socioeconomic development in China. One of the traffic arteries in Shenzhen is an urban expressway that is under construction and that runs across environmentally sensitive areas (ESAs). The environmental pollution from urban expressways is critical, due to the characteristics of expressways such as high runoff coefficients, considerable contaminant accumulation, and complex pollutant ingredi- ents. ESAs are vulnerable to anthropogenic disturbances and hence should be given special attention. In order to evaluate the environmental sensitivity along this urban expressway and minimize the influences of the ongoing road construction and future operation on the surrounding ecosystem, the environmental sensitivity of the relevant area was evaluated based on the application of a geographic information sys- tem (GIS). A final ESA map was classified into four environmental sensitivity levels; this classification indicates that a large proportion of the expressway passes through areas of high sensitivity, representing 11.93 km or 52.3% of the total expressway, and more than 90% of the total expressway passes through ESAs. This study provides beneficial information for optimal layout schemes of initial rainfall runofftreatment facilities developed from low-impact development (LID) techniques in order to minimize the impact of polluted road runoff on the surrounding ecological environment.
基金This research is funded by Natural Science Foundation of China (71171001) the Ministry of Education's General Project of Humanitarian and Social Science (Approval No.11YJC630107).
文摘This paper examines the cost of environmental regulation and the environmental total factor productivity (TFP) with directional distance function and the Malmquist-Luenberger (ALL) index respectively, using inputs and output data of 36 two-digit industries over the period 1998- 2010. It finds that Chinese industries incur a relatively high environmental regulatory cost and that China has paid a high price fulfilling its promise to emissions mitigation. A comparison between conventional and environmental TFP shows that the two indicators for all industries declined on average, but a hypothesis test reveals insignificant difference between the two. In addition, the rise in environmental TFP is mainly due to technological progress, which is consistent with findings of many researches; analysis demonstrates signs of absolute convergence of environmental TFP.
文摘According to sensitivity to environment, rice varieties can be classified into a strong environmentally sensitive variety, a weak environmentally sensitive variety and an environmentally insensitive variety. The general method that was used to evaluate the environmental sensitivity (ES) of rice variety was put forward in this paper. ESs of varieties were evaluated as follows:(1) ES of indica-japonica hybird rice was more sensitive than that of japonica rice. (2)The order of ESs of japonica type varieties was medium-maturing late japonica variety > early-maturing late japonica variety > late-maturing medium japonica variety > medium-maturing medium japonica variety. (3)There was a significant difference in ESs among varieties of the same japonica type rice, too. Some problems, such as the principles of rather late-maturing rice planted northward, were also discussed at the end of this paper.
基金Supported by Science and Technology Planning Project of Hebei Academy of Sciences (11128)Major Science and Technology Planning Project of Hebei Academy of Sciences (11104)
文摘[Objective] This study aimed to assess the vulnerability of ecological environment in Hebei Province.[Method] Based on ArcGIS,by using the dominant factor and maximum limits factor method,we established the sensitivity-reality indicator system and assessment model of the eco-environment vulnerability in Hebei Province to quantitatively evaluate its eco-environment vulnerability,and analyzed its spatial distribution.[Result] The status quo of environmental degradation was inconsistent with the sensitivity of eco-environment in Hebei Province.The area of severely vulnerable region accounted for only 4.1% of total area in Hebei Province,mainly distributed in nine counties or districts of Baxia region,Zhangjiakou,northwestern Hebei,which was covered with mountains and basins,showing bands,which resulted from the vulnerability of soil erosion and land desertification.In addition,the moderately vulnerable region made up 38.4%,having the largest proportion,and mainly distributed in the mountain and basin region in northwestern Hebei,Yanshan Mountain and the most regions of Taihang Mountain,due to the vulnerability of soil erosion.At the same time,there were also large patches of moderately vulnerable region in Bashang and Baxia of Zhangjiakou,owning to the vulnerability of land desertification.Besides,most plains were mildly vulnerable and slightly vulnerable regions,and their areas accounted for 25.1% and 32.4% respectively of total area.[Conclusion] The research could provide scientific references for safeguarding the ecological security and main functional district planing of Hebei Province.
基金supported by the National Key Research and Development Program of China (2017YFB0504203)the Central Government Guides Local Development Special Fund (2017L3012)the National Natural Science Foundation of China (41771468, 41471362)。
文摘Land degradation has a major impact on environmental and socio-economic sustainability. Scientific methods are necessary to monitor the risk of land degradation. In this study, the environmental sensitive area index(ESAI) was utilized to assess land degradation sensitivity and convergence analysis in Korla, a typical oasis city in Xinjiang of China, which is located on the northeast border of the Tarim Basin. A total of 18 indicators depicting soil, climate, vegetation, and management qualities were used to illustrate spatial-temporal patterns of land degradation sensitivity from 1994 to 2018. We investigated the causes of spatial convergence and divergence based on the Ordinary Least Squares(OLS) and Geographically Weighted Regression(GWR) models. The results show that the branch of the Tianshan Mountains and oasis plain had a low sensitivity to land degradation, while the Tarim Basin had a high risk of land degradation. More than two-thirds of the study area can be categorized as "critical" sensitivity classes. The largest percentage(32.6%) of fragile classes was observed for 2006. There was no significant change in insensitive or low-sensitivity areas, which accounted for less than 0.4% of the entire observation period. The ESAI of the four time periods(1994–1998, 1998–2006, 2006–2010, and 2010–2018) formed a series of convergence patterns. The convergence patterns of 1994–1998 and 1998–2006 can be explained by the government's efforts to "Returning Farmland to Forests" and other governance projects. In 2006–2010, the construction of afforested work intensified, but industrial development and human activities affected the convergence pattern. The pattern of convergence in most regions between 2010 and 2018 can be attributed to the government's implementation of a series of key ecological protection projects, which led to a decrease in sensitivity to land degradation. The results of this study altogether suggest that the ESAI convergence analysis is an effective early warning method for land degradation sensitivity.
基金This work was financially supported by the National Natural Science Foundation of China (No. 39870227) this paper was reported on International Symposium on Radiation Technology in Emerging Industry Application, held on Nov. 6-10, 2001 in Beijing, China
文摘Poly(N,N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by gamma-irradiation showed obvious temperature-sensitivity in a temperature range of 38-40degreesC and pH-sensitivity at pH=2.5. They also showed electric response behavior although it was not typical. The hydrogels were used in controlled release at different pH, temperature, and electric voltage. The release rates of methylene blue (MB) from the gels at 52degreesC and pH=1.24 were faster than those at 20degreesC and pH=10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that without electric field.
基金National Natural Science Foundation of China(Nos.21977082,22037002 and 21472148)the Natural Science Basic Research Program of Shaanxi(No.2020JC-38).
文摘We here present a Förster resonance energy transfer(FRET)-based and environment-sensitive fluorescent probe VG-1 for vicinal-dithiol-containing proteins(VDPS).VG-1 uniquely contalns two sites sensitive to the protein environment(SPE)thus it shows weak fluorescence in both blue and green channels(a low FRET efficiency)in solution.After specifically binding with VDPs,its fuorescence in the green channel increases,while that in the blue channel disappears,achieving the specific detection of VDPs.The obvioussignal changes in fluorescence may be attributed to that the increased rigidity of the molecular skeletons causes the enhanced FRET eficiency,The probe also achleved the cell super-resolution imaging of VDPs and the confocal imaging of VDPs in zebrafish.
基金supported by University Grants Commission–Special Assistance Program(DSA I)[grant number F.510/7/DSA-I/2015(SAP-I)],Government of India,New Delhi.
文摘This paper develops an economic production quantity(EPQ)model for a singlemanufacturer multi-retailer(SMMR)production and reworking system with green and environmental sensitive customer demand.The minimum cost of the manufacturer has obtained under carbon emissions(CE)policies and discrete ordering cost reduction.The model is used to optimize the total number of shipments,greening investment level,environmental measure,and lot size for productions and rework.This research work determines that the manufacturer’s and retailer’s profits will be increased after considering the environmental and green dependent demand of customers.Further,the development of green and environmental demand is proposed to minimize the CE and maximize the demand for the customers.In the existing literature,no discrete investment is developed for reducing the cost of ordering for the retailer/buyer.However,in this paper,we have introduced it.We provide numerical examples to explain the models and determine the significance of model parameters.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 49894170, 49725308)Chinese Academy of Sciences (Nos. KZ-951-A1-402 & KZ-952-S1-419)State Committee of Science and Technology of China.
文摘17 samples were collected from aeolian and lacustrine profiles within the environment sensitive zone of the Loess Plateau, and an experimental method was established which is suitable for pollen extraction from aeolian sediment. A comparative study of pollen dating was carried out using the accelerator mass spectrometry (AMS)14C dating of known age samples, and then an experiment with the pollen concentrates was performed. The results indicate that pollen that has been deposited simultaneously with sediment in a stable environment can provide reliable ages. This technique will provide a way of improving the chronological framework for the Loess Plateau since the late Pleistocene. TheI4c dating was combined with field investigations, and from the geological record within this zone, evidence was extracted of four major monsoon precipitation changes during the transition from the late Pleistocene to Holocene.
基金supported by Singapore University of Technology and Design(No.T1SRCI17126)A*STAR under its Advanced Manufacturing and Engineering Program(No.A2083c0051)+1 种基金the National Natural Science Foundation of China(Nos.21878286,21908216)Dalian Institute of Chemical Physics(Nos.DMTO201603,TMSR201601)。
文摘Energy transfer and electron transfer are both fundamental mechanisms enabling numerous functional materials and applications.While most materials systems employ either energy transfer or electron transfer,the combined effect of energy and electron transfer processes in a single donor/acceptor system remains largely unexplored.Herein,we demonstrated the energy transfer followed by electron transfer(ETET)process in a molecular dyad TPE-NBD.Due to energy transfer,the fluorescence of TPE-NBD was greatly enhanced in non-polar solvents.In contrast,polar solvents activated subsequent electron transfer and markedly quenched the emission of TPE-NBD.Consequently,ETET endows TPE-NBD with significant polarity sensitivities.We expect that employing ETET could generate many functional materials with unprecedented properties,i.e.,for single laser powered multicolor fluorescence imaging and sensing.