Sulfuric acid slag,a common byproduct with high iron content,poses challenges due to its high levels of harmful impurities and is often discarded as solid waste,leading to significant environmental and water pollution...Sulfuric acid slag,a common byproduct with high iron content,poses challenges due to its high levels of harmful impurities and is often discarded as solid waste,leading to significant environmental and water pollution.To address this issue and improve resource utilization,the preparation process of oxidized pellets from sulfuric acid slag was studied,exploring suitable pelletizing systems and thermal parameters.Additionally,the removal of harmful elements and the consolidation mechanism were established during the oxidation roasting process.The findings revealed that sulfuric acid slag along with specific processing conditions,such as using two high-pressure grinding rolls and adding 1.25 wt.%bentonite,resulted in the production of qualified green pellets with desirable physical properties.Through a thermal treatment process involving preheating and roasting,the desulfurization rate of the pellets reached 95.55%and the removal efficiency of arsenic achieved 27.11%.Hematite recrystallizes,shrinks,and forms a reticulated structure with Fe2O3 recrystallization as the backbone,resulting in higher consolidation strength.展开更多
Pueraria montana is a perennial twining vine species of Pueraria in Leguminosae.Because of its fast growth and strong climbing and covering ability,this species has the potential threat of invading forest ecosystem.Ba...Pueraria montana is a perennial twining vine species of Pueraria in Leguminosae.Because of its fast growth and strong climbing and covering ability,this species has the potential threat of invading forest ecosystem.Based on the investigation of the occurrence and harm of P.montana in the"four mountains"forest ecosystem in the central urban area of Chongqing,combined with its growth habits and biological characteristics,we comprehensively evaluated its harm risk.The results show that P.montana is widely distributed in the forest ecosystem within the"four mountains"in the central urban area of Chongqing.On average,there was a distribution site of P.montana every 1.38 km of forest road with a scale of 0.43 hm 2/survey point and a coverage of about 42.86%.P.montana mainly occupy forest land by covering and climbing,threatening the original vegetation of forest land.It grows rapidly,and its ability of diffusion and colonization is very strong.The average length of new branches was 11.52 m/year,and the number of effective tillers was 5.25.According to National Forestry Pest Risk Analysis Index System,the risk assessment value of P.montana was 2.51,so it is a medium-risk harmful plant to forestry.It is suggested that the forestry department should strengthen the management of P.montana to prevent its further spread.展开更多
Coal seams can enrich a variety of harmful trace elements under specific geological conditions.The spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of eac...Coal seams can enrich a variety of harmful trace elements under specific geological conditions.The spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of each element content are different.The harmful elements released in the process of coal mining and utilization will cause serious harm to the environment and the human body.It is of great resource significance to study the geochemistry of coal that affects the enrichment and distribution characteristics of harmful trace elements.Based on the domestic and foreign literature on coal geochemistry in Guizhou published by previous investigators,this study counted 1097 sample data from 23 major coal-producing counties in Guizhou Province,systematically summarized the relevant research results of harmful trace elements in the coal of Guizhou,and revealed the overall distribution and enrichment characteristics of harmful trace elements in the coal of Guizhou.The results show that the average contents of Cd,Pb,Se,Cu,Mo,U,V,As,Hg,and Cr in coal of Guizhou are higher than those in Chinese coal and world coal.A variety of harmful trace elements in the coal of Guizhou have high background values,especially in Liupanshui,Xingyi and Qianbei coalfield.The enrichment of various harmful trace elements in the Late Permian coal in Guizhou is mainly related to the combined action of various geological and geochemical factors.The supply of terrigenous debris and sedimentary environment may be the basic background of the enrichment of harmful elements in western Guizhou,while low-temperature hydrothermal activity and volcanic ash deposition may be the main reasons for the enrichment of harmful elements in southwestern Guizhou.展开更多
Tea,a globally cultivated crop renowned for its uniqueflavor profile and health-promoting properties,ranks among the most favored functional beverages worldwide.However,diseases severely jeopardize the production and qu...Tea,a globally cultivated crop renowned for its uniqueflavor profile and health-promoting properties,ranks among the most favored functional beverages worldwide.However,diseases severely jeopardize the production and quality of tea leaves,leading to significant economic losses.While early and accurate identification coupled with the removal of infected leaves can mitigate widespread infection,manual leaves removal remains time-con-suming and expensive.Utilizing robots for pruning can significantly enhance efficiency and reduce costs.How-ever,the accuracy of object detection directly impacts the overall efficiency of pruning robots.In complex tea plantation environments,complex image backgrounds,the overlapping and occlusion of leaves,as well as small and densely harmful leaves can all introduce interference factors.Existing algorithms perform poorly in detecting small and densely packed targets.To address these challenges,this paper collected a dataset of 1108 images of harmful tea leaves and proposed the YOLO-DBD model.The model excels in efficiently identifying harmful tea leaves with various poses in complex backgrounds,providing crucial guidance for the posture and obstacle avoidance of a robotic arm during the pruning process.The improvements proposed in this study encompass the Cross Stage Partial with Deformable Convolutional Networks v2(C2f-DCN)module,Bi-Level Routing Atten-tion(BRA),Dynamic Head(DyHead),and Focal Complete Intersection over Union(Focal-CIoU)Loss function,enhancing the model’s feature extraction,computation allocation,and perception capabilities.Compared to the baseline model YOLOv8s,mean Average Precision at IoU 0.5(mAP0.5)increased by 6%,and Floating Point Operations Per second(FLOPs)decreased by 3.3 G.展开更多
By establishing a distribution and environmental factor database of 21 typical harmful dinoflagellates in global waters,the MaxEnt model was used to predict shifts in the habitat of harmful dinoflagellates in Chinese ...By establishing a distribution and environmental factor database of 21 typical harmful dinoflagellates in global waters,the MaxEnt model was used to predict shifts in the habitat of harmful dinoflagellates in Chinese waters under global climate change.The results revealed that offshore distance was the most important predictive factor and that surface seawater temperature(SST),primary productivity,and nitrate concentration were the key ecological factors influencing the distribution of harmful dinoflagellates.Under the low greenhouse gas emission scenario defined by the Intergovernmental Panel on Climate Change(IPCC),by approximately 2050,17 of the 21harmful dinoflagellate species in high-suitability areas(HSA)will migrate northward,six species will migrate eastward,and six species will expand their HSA.By 2100,approximately 18 of the 21 harmful dinoflagellate species in HSA will have migrated northward,seven species will have migrated eastward,and four species will have expanded their HSA.Notably,the HSA content of highly toxic Alexandrium minutum is expected to increase by 13.4%and 9.4%by 2050 and 2100,respectively.Under the high greenhouse gas emissions,there will be 17species migrating northward,6 species migrating eastward,and 4 species increasing in their size in HSA by 2050;moreover,there will be 16 species migrating northward,2 migrating eastward,and 4 species according to their size of HSA by 2100.Specifically,the HSA of A.minutum is predicted to increase by 7.0%and 25.9%by 2050 and 2100,respectively.Notably,A.ostenfeldii,which is currently seldom present in the China seas,is predicted to exhibit an HSA in most coastal areas of the Yellow Sea,the Bohai Sea,the Hangzhou Bay,the Zhejiang Coast,and the Beibu Gulf of the South China Sea.Conversely,the HSA of Noctiluca scintillans,a typical red-tide species,will be reduced by 7%–90%.The northward migration of Karenia mikimotoi exceeded 100 km and 300 km under low and high greenhouse gas emission scenarios,respectively.These changes underscore the significant impact of climate change on the distribution and habitat suitability of harmful dinoflagellates,thus indicating a potential shift in their ecological dynamics and consequent effects on marine ecosystems.展开更多
In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively...In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively analyzed. The ultrasonic extraction technology was optimized by Box-Behnken response surface method, and the total flavonoid content of 21 kinds of Acanthopanax senticosus(Rupr. et Maxim.) Harms from different producing areas were analyzed by cluster analysis. The optimal process conditions were determined as ultrasonic time 30 min, solid-liquid ratio 1 : 12 and ultrasonic power 250 W, and the average yield of the total flavonoid was 1.453 mg·g^ (-1). By optimizing the ultrasonic-assisted extraction method, the total flavonoid content from different producing areas was compared in the experiment, which provided certain data support for the optimization of the extraction process in the future and laid a certain theoretical foundation for the quality analysis of Chinese medicinal materials.展开更多
Hail is one of meteorological disasters affecting crop growth in Ulanqab City.It happens frequently from May to September,and this period is also the main growing season of crops.In this period,hail will cause damage ...Hail is one of meteorological disasters affecting crop growth in Ulanqab City.It happens frequently from May to September,and this period is also the main growing season of crops.In this period,hail will cause damage to crops,make farmland soil harden,and bring varying degrees of harm to agricultural production.Artificial hail suppression is an important scientific and technological means for disaster prevention and mitigation.It is necessary to strengthen the monitoring,analysis and forecast of severe convection weather,intensify the release of early warning information of hail weather,provide accurate and reliable real-time information for the implementation of artificial hail suppression operations,strengthen the implementation of artificial weather modification,effectively carry out artificial hail suppression operations,and avoid and reduce the impact of hail disaster.展开更多
Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station （DNPS） in 1994. This...Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station （DNPS） in 1994. This study analyzed the changes of water temperature and harmful algal blooms （HABs） for two periods： 1983-1993 and 1994-2004, using in situ and satellite data. Results showed that yearly mean surface water temperature （SWT） and Chl-a concentration （Chl-a） increased by 1.1 ℃ and 1.9 mg/m^3, respectively, after 1994. The monthly occurrence of HAB was found to have increased also. HABs appeared only in spring and autumn before 1994, but occurred all the year round after 1994. SWT, Chl-a and HABs all increased significantly in May. Those changes were associated with environmental changes in this area, such as thermal discharge from the DNPS and enhancement of eutrophication from human activities around the Daya Bay.展开更多
目前普通系统评价/Meta分析都被要求遵循PRISMA(Preferred Reporting Items for Systematic Reviews and Meta-Analyses)进行规范报告。PRISMA harms清单是PRISMA报告规范的衍生版,其主要针对安全性系统评价如何进行报告提出条件要求。P...目前普通系统评价/Meta分析都被要求遵循PRISMA(Preferred Reporting Items for Systematic Reviews and Meta-Analyses)进行规范报告。PRISMA harms清单是PRISMA报告规范的衍生版,其主要针对安全性系统评价如何进行报告提出条件要求。PRISMA harms清单包括标题、摘要、前言、方法、结果、讨论和资助等需要报告的27个条目内容。该规范包括了清单、详尽的解释性文本以方便使用。通过应用PRISMA harms清单,作者、期刊编辑和同行评议者可促进安全性系统评价报告的质量。展开更多
In order to realize the detection and analysis of microalgae in sediment samples with complex scenes, the project takes advantage of the character of microalgae that they can auto-fluoresce when exposed to the illumin...In order to realize the detection and analysis of microalgae in sediment samples with complex scenes, the project takes advantage of the character of microalgae that they can auto-fluoresce when exposed to the illumination of certain exciation waves. The project takes grey-scale and fluorescent pictures of microalgae in the same field of view and uses the image processing technique to deal with the images, such as threshold segmentation, contour and texture analysis and pattern recognition. The results show that the fluorescent image can effectively elimate the yawp in the complex background and make the consequent image processing more effective and easy. Then the project comes to the conclusion that fluorescence-assisted image processing can realize the detection and analysis of microalgae in sediment samples containing complex scenes.展开更多
With the popularization of the Internet,this technology has changed the form of information dissemination. The information will spread quickly when food product harm crisis happens,and the phenomenon that information ...With the popularization of the Internet,this technology has changed the form of information dissemination. The information will spread quickly when food product harm crisis happens,and the phenomenon that information of product-harm spills over is very common. This article is based on " Frustration- Misbehaving" research paradigm,combined with the information dissemination motivation theory,discusses that the fitness between the consumers and the crisis will promote consumers' dysfunctional customer behavior. The study found that the fitness between the consumers and the crisis has significant effect on consumers' dysfunctional customer behavior,perceived social damage has a mediator effect between fitness and consumers' misbehavior,and the moderating effect of consumers' aggression tendency is significant,but not the emotional tendency. The theoretical contribution and valuable implications of findings for communication of crisis management are discussed at last.展开更多
Through the investigation and analysis of the wild boars in Mingtong Town, Chengkou, Chongqing, it was concluded that the area had long been seri- ously affected by wild boars and some of the human activities were pot...Through the investigation and analysis of the wild boars in Mingtong Town, Chengkou, Chongqing, it was concluded that the area had long been seri- ously affected by wild boars and some of the human activities were potentially threatened, and the potential threat areas were identified. Corresponding suggestions were proposed to guide the prevention and control work, so as to protect the habi- tat and reproduction of wildlife and ensure the normal production and life of the masses.展开更多
Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal ...Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal waters that facilitate its rapid expansion, the effects of temperature, salinity and irradiance on the growth of P. globosa from the South China Sea were examined in the laboratory. The saturating irradiance for the growth ofP. globosa （Is） was 60 μmol/（m^2·s）, which was lower than those of other harmful algal species （70-114μmol/（m^2·s））. A moderate growth rate of 0.22/d was observed at 2 μmol/（m^2·s） （the minimum irradiance in the experiment）, and photo-inhibition did not occur at 230 μmol/（m^2·s） （the maximum irradiance in the experiment）. Exposed to 42 different combinations of temperatures （10- 31 ℃） and salinities （10-40） under saturating irradiance, P. globosa exhibited its maximum specific growth rate of 0.80/d at the combinations of 24℃ and 35, and 27℃ and 40. The optimum growth rates （〉0.80/d） were observed at temperatures ranging from 24 to 27℃ and salinities from 35 to 40. While P. globosa was able to grow well at temperatures from 20℃ to 31℃ and salinities from 20 to 40, it could not grow at temperatures lower than 15℃ or salinities lower than 15. Factorial analysis revealed that temperature and salinity has similar influences on the growth of this species. This strain ofP. globosa not only prefers higher temperatures and higher salinity, but also possesses a flexible nutrient competing strategy, adapted to lower irradiance. Therefore, the P. globosa population from South China Sea should belong to a new ecotype. There is also a potentially high risk of blooms developing in this area throughout the year.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities of Central South University(2023ZZTS0506).
文摘Sulfuric acid slag,a common byproduct with high iron content,poses challenges due to its high levels of harmful impurities and is often discarded as solid waste,leading to significant environmental and water pollution.To address this issue and improve resource utilization,the preparation process of oxidized pellets from sulfuric acid slag was studied,exploring suitable pelletizing systems and thermal parameters.Additionally,the removal of harmful elements and the consolidation mechanism were established during the oxidation roasting process.The findings revealed that sulfuric acid slag along with specific processing conditions,such as using two high-pressure grinding rolls and adding 1.25 wt.%bentonite,resulted in the production of qualified green pellets with desirable physical properties.Through a thermal treatment process involving preheating and roasting,the desulfurization rate of the pellets reached 95.55%and the removal efficiency of arsenic achieved 27.11%.Hematite recrystallizes,shrinks,and forms a reticulated structure with Fe2O3 recrystallization as the backbone,resulting in higher consolidation strength.
基金Supported by Special Project of Performance Incentive and Guidance for Scientific Research Institutions in Chongqing(cstc2022jxjl80025).
文摘Pueraria montana is a perennial twining vine species of Pueraria in Leguminosae.Because of its fast growth and strong climbing and covering ability,this species has the potential threat of invading forest ecosystem.Based on the investigation of the occurrence and harm of P.montana in the"four mountains"forest ecosystem in the central urban area of Chongqing,combined with its growth habits and biological characteristics,we comprehensively evaluated its harm risk.The results show that P.montana is widely distributed in the forest ecosystem within the"four mountains"in the central urban area of Chongqing.On average,there was a distribution site of P.montana every 1.38 km of forest road with a scale of 0.43 hm 2/survey point and a coverage of about 42.86%.P.montana mainly occupy forest land by covering and climbing,threatening the original vegetation of forest land.It grows rapidly,and its ability of diffusion and colonization is very strong.The average length of new branches was 11.52 m/year,and the number of effective tillers was 5.25.According to National Forestry Pest Risk Analysis Index System,the risk assessment value of P.montana was 2.51,so it is a medium-risk harmful plant to forestry.It is suggested that the forestry department should strengthen the management of P.montana to prevent its further spread.
基金supported by National Natural Science Foundation of China(No.51964009)。
文摘Coal seams can enrich a variety of harmful trace elements under specific geological conditions.The spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of each element content are different.The harmful elements released in the process of coal mining and utilization will cause serious harm to the environment and the human body.It is of great resource significance to study the geochemistry of coal that affects the enrichment and distribution characteristics of harmful trace elements.Based on the domestic and foreign literature on coal geochemistry in Guizhou published by previous investigators,this study counted 1097 sample data from 23 major coal-producing counties in Guizhou Province,systematically summarized the relevant research results of harmful trace elements in the coal of Guizhou,and revealed the overall distribution and enrichment characteristics of harmful trace elements in the coal of Guizhou.The results show that the average contents of Cd,Pb,Se,Cu,Mo,U,V,As,Hg,and Cr in coal of Guizhou are higher than those in Chinese coal and world coal.A variety of harmful trace elements in the coal of Guizhou have high background values,especially in Liupanshui,Xingyi and Qianbei coalfield.The enrichment of various harmful trace elements in the Late Permian coal in Guizhou is mainly related to the combined action of various geological and geochemical factors.The supply of terrigenous debris and sedimentary environment may be the basic background of the enrichment of harmful elements in western Guizhou,while low-temperature hydrothermal activity and volcanic ash deposition may be the main reasons for the enrichment of harmful elements in southwestern Guizhou.
文摘Tea,a globally cultivated crop renowned for its uniqueflavor profile and health-promoting properties,ranks among the most favored functional beverages worldwide.However,diseases severely jeopardize the production and quality of tea leaves,leading to significant economic losses.While early and accurate identification coupled with the removal of infected leaves can mitigate widespread infection,manual leaves removal remains time-con-suming and expensive.Utilizing robots for pruning can significantly enhance efficiency and reduce costs.How-ever,the accuracy of object detection directly impacts the overall efficiency of pruning robots.In complex tea plantation environments,complex image backgrounds,the overlapping and occlusion of leaves,as well as small and densely harmful leaves can all introduce interference factors.Existing algorithms perform poorly in detecting small and densely packed targets.To address these challenges,this paper collected a dataset of 1108 images of harmful tea leaves and proposed the YOLO-DBD model.The model excels in efficiently identifying harmful tea leaves with various poses in complex backgrounds,providing crucial guidance for the posture and obstacle avoidance of a robotic arm during the pruning process.The improvements proposed in this study encompass the Cross Stage Partial with Deformable Convolutional Networks v2(C2f-DCN)module,Bi-Level Routing Atten-tion(BRA),Dynamic Head(DyHead),and Focal Complete Intersection over Union(Focal-CIoU)Loss function,enhancing the model’s feature extraction,computation allocation,and perception capabilities.Compared to the baseline model YOLOv8s,mean Average Precision at IoU 0.5(mAP0.5)increased by 6%,and Floating Point Operations Per second(FLOPs)decreased by 3.3 G.
基金The National Key Research and Development Program of China under contract Nos 2019YFE0124700 and 2022YFC3106002。
文摘By establishing a distribution and environmental factor database of 21 typical harmful dinoflagellates in global waters,the MaxEnt model was used to predict shifts in the habitat of harmful dinoflagellates in Chinese waters under global climate change.The results revealed that offshore distance was the most important predictive factor and that surface seawater temperature(SST),primary productivity,and nitrate concentration were the key ecological factors influencing the distribution of harmful dinoflagellates.Under the low greenhouse gas emission scenario defined by the Intergovernmental Panel on Climate Change(IPCC),by approximately 2050,17 of the 21harmful dinoflagellate species in high-suitability areas(HSA)will migrate northward,six species will migrate eastward,and six species will expand their HSA.By 2100,approximately 18 of the 21 harmful dinoflagellate species in HSA will have migrated northward,seven species will have migrated eastward,and four species will have expanded their HSA.Notably,the HSA content of highly toxic Alexandrium minutum is expected to increase by 13.4%and 9.4%by 2050 and 2100,respectively.Under the high greenhouse gas emissions,there will be 17species migrating northward,6 species migrating eastward,and 4 species increasing in their size in HSA by 2050;moreover,there will be 16 species migrating northward,2 migrating eastward,and 4 species according to their size of HSA by 2100.Specifically,the HSA of A.minutum is predicted to increase by 7.0%and 25.9%by 2050 and 2100,respectively.Notably,A.ostenfeldii,which is currently seldom present in the China seas,is predicted to exhibit an HSA in most coastal areas of the Yellow Sea,the Bohai Sea,the Hangzhou Bay,the Zhejiang Coast,and the Beibu Gulf of the South China Sea.Conversely,the HSA of Noctiluca scintillans,a typical red-tide species,will be reduced by 7%–90%.The northward migration of Karenia mikimotoi exceeded 100 km and 300 km under low and high greenhouse gas emission scenarios,respectively.These changes underscore the significant impact of climate change on the distribution and habitat suitability of harmful dinoflagellates,thus indicating a potential shift in their ecological dynamics and consequent effects on marine ecosystems.
基金Supported by the Breeding Techniques for New Varieties of Acanthopanax senticosus(CZKYF2022-1-B023)。
文摘In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively analyzed. The ultrasonic extraction technology was optimized by Box-Behnken response surface method, and the total flavonoid content of 21 kinds of Acanthopanax senticosus(Rupr. et Maxim.) Harms from different producing areas were analyzed by cluster analysis. The optimal process conditions were determined as ultrasonic time 30 min, solid-liquid ratio 1 : 12 and ultrasonic power 250 W, and the average yield of the total flavonoid was 1.453 mg·g^ (-1). By optimizing the ultrasonic-assisted extraction method, the total flavonoid content from different producing areas was compared in the experiment, which provided certain data support for the optimization of the extraction process in the future and laid a certain theoretical foundation for the quality analysis of Chinese medicinal materials.
文摘Hail is one of meteorological disasters affecting crop growth in Ulanqab City.It happens frequently from May to September,and this period is also the main growing season of crops.In this period,hail will cause damage to crops,make farmland soil harden,and bring varying degrees of harm to agricultural production.Artificial hail suppression is an important scientific and technological means for disaster prevention and mitigation.It is necessary to strengthen the monitoring,analysis and forecast of severe convection weather,intensify the release of early warning information of hail weather,provide accurate and reliable real-time information for the implementation of artificial hail suppression operations,strengthen the implementation of artificial weather modification,effectively carry out artificial hail suppression operations,and avoid and reduce the impact of hail disaster.
基金This study was jointly supported by the following funds awarded to Professor Danling TANG:Guangdong Natural Science Foundation(05102008 and 04001306),ChinaKey Innovation Project of Chinese Academy of Sciences(CAS)(KZCX3-SW-227-3)+3 种基金"0ne Hundred Talents Program"of CAS(Ybrjh0403)Authors are grateful to projects of South China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences(2007TS10 and 2007ZD03)High-tech Research and Development Program of China(2006AA100303)Chinese Ecosystem Research Network(http://www.cerndata.ac.cn),Dr.Guifeng WEI of Jinan University and the Key Innovation Project of CAS(KZCX3-SW-214).
文摘Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station （DNPS） in 1994. This study analyzed the changes of water temperature and harmful algal blooms （HABs） for two periods： 1983-1993 and 1994-2004, using in situ and satellite data. Results showed that yearly mean surface water temperature （SWT） and Chl-a concentration （Chl-a） increased by 1.1 ℃ and 1.9 mg/m^3, respectively, after 1994. The monthly occurrence of HAB was found to have increased also. HABs appeared only in spring and autumn before 1994, but occurred all the year round after 1994. SWT, Chl-a and HABs all increased significantly in May. Those changes were associated with environmental changes in this area, such as thermal discharge from the DNPS and enhancement of eutrophication from human activities around the Daya Bay.
文摘In order to realize the detection and analysis of microalgae in sediment samples with complex scenes, the project takes advantage of the character of microalgae that they can auto-fluoresce when exposed to the illumination of certain exciation waves. The project takes grey-scale and fluorescent pictures of microalgae in the same field of view and uses the image processing technique to deal with the images, such as threshold segmentation, contour and texture analysis and pattern recognition. The results show that the fluorescent image can effectively elimate the yawp in the complex background and make the consequent image processing more effective and easy. Then the project comes to the conclusion that fluorescence-assisted image processing can realize the detection and analysis of microalgae in sediment samples containing complex scenes.
基金Supported by National Natural Science Foundation of China(71073064)Fundamental Research Funds for the Central Universities(2013SC38)
文摘With the popularization of the Internet,this technology has changed the form of information dissemination. The information will spread quickly when food product harm crisis happens,and the phenomenon that information of product-harm spills over is very common. This article is based on " Frustration- Misbehaving" research paradigm,combined with the information dissemination motivation theory,discusses that the fitness between the consumers and the crisis will promote consumers' dysfunctional customer behavior. The study found that the fitness between the consumers and the crisis has significant effect on consumers' dysfunctional customer behavior,perceived social damage has a mediator effect between fitness and consumers' misbehavior,and the moderating effect of consumers' aggression tendency is significant,but not the emotional tendency. The theoretical contribution and valuable implications of findings for communication of crisis management are discussed at last.
文摘Through the investigation and analysis of the wild boars in Mingtong Town, Chengkou, Chongqing, it was concluded that the area had long been seri- ously affected by wild boars and some of the human activities were potentially threatened, and the potential threat areas were identified. Corresponding suggestions were proposed to guide the prevention and control work, so as to protect the habi- tat and reproduction of wildlife and ensure the normal production and life of the masses.
基金Supported by the National Natural Science Foundation of China(NSFC)(Nos.41576159,U1133003)the National High Technology Research and Development Program of China(863 Program)(No.2013AA065805)
文摘Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal waters that facilitate its rapid expansion, the effects of temperature, salinity and irradiance on the growth of P. globosa from the South China Sea were examined in the laboratory. The saturating irradiance for the growth ofP. globosa （Is） was 60 μmol/（m^2·s）, which was lower than those of other harmful algal species （70-114μmol/（m^2·s））. A moderate growth rate of 0.22/d was observed at 2 μmol/（m^2·s） （the minimum irradiance in the experiment）, and photo-inhibition did not occur at 230 μmol/（m^2·s） （the maximum irradiance in the experiment）. Exposed to 42 different combinations of temperatures （10- 31 ℃） and salinities （10-40） under saturating irradiance, P. globosa exhibited its maximum specific growth rate of 0.80/d at the combinations of 24℃ and 35, and 27℃ and 40. The optimum growth rates （〉0.80/d） were observed at temperatures ranging from 24 to 27℃ and salinities from 35 to 40. While P. globosa was able to grow well at temperatures from 20℃ to 31℃ and salinities from 20 to 40, it could not grow at temperatures lower than 15℃ or salinities lower than 15. Factorial analysis revealed that temperature and salinity has similar influences on the growth of this species. This strain ofP. globosa not only prefers higher temperatures and higher salinity, but also possesses a flexible nutrient competing strategy, adapted to lower irradiance. Therefore, the P. globosa population from South China Sea should belong to a new ecotype. There is also a potentially high risk of blooms developing in this area throughout the year.
