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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing
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作者 Lina Cai Jie Yin +3 位作者 Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期66-86,共21页
Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was propose... Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture areas.This methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental factors.The fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 m.In the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in detail.The results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture area.As for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open waters.The water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the future.the fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world. 展开更多
关键词 mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis
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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM
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作者 WANG Yanxia YANG Lisha +1 位作者 HUANG Xiaoyuan ZHOU Ruliang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2025-2042,共18页
Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are n... Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources. 展开更多
关键词 high temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection
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Effect of dissolved-oxygen on the flotation behavior of pyrite at high altitude area
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作者 Yan Miao Guangke Ye Guofan Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2148-2158,共11页
With the continuous development of mineral resources to high altitude areas,the study of sulfide ore flotation in unconventional systems has been emphasized.There is a consensus that moderate oxidation of sulfide ore ... With the continuous development of mineral resources to high altitude areas,the study of sulfide ore flotation in unconventional systems has been emphasized.There is a consensus that moderate oxidation of sulfide ore is beneficial to flotation,but the specific suitable dissolved oxygen value is inconclusive,and there are few studies on sulfide ore flotation under low dissolved oxygen environment at high altitude.In this paper,we designed and assembled an atmosphere simulation flotation equipment to simulate the flotation of pyrite at high altitude by controlling the partial pressure of N_(2)/O_(2) and dissolved oxygen under atmospheric conditions.X-ray photoelectron spec-troscopy(XPS),atomic force microscope(AFM),Fourier transform infrared spectrometer(FT-IR),UV-vis spectrophotometer,zeta po-tential,and contact angle measurements were used to reveal the effects of surface oxidation and agent adsorption on pyrite at high altitude(4600 m dissolved oxygen(DO)=4.0 mg/L).The results of pure mineral flotation indicated that the high altitude and low dissolved oxy-gen environment is favorable for pyrite flotation.Contact angle measurements and XPS analysis showed that the high altitude atmosphere nslows down the oxidation of pyrite surface,facilitates S_(n)^(2-)/S^(0) production and enhances surface hydrophobicity.Electrochemical calcula-tions and zeta potential analysis showed that the influence of atmosphere on the form of pyrite adsorption is small,and the different atmo-spheric conditions are consistent with dixanthogen electrochemical adsorption,with lower Zeta potential under high altitude atmosphere and significant potential shift after sodium isobutyl xanthate(SIBX)adsorption.The results of FT-IR,UV-vis,and AFM analysis showed that SIBX adsorbed more on the surface of pyrite under high altitude atmosphere and adsorbed on the surface in a mesh structure com-posed of column/block.The results of the experimental study revealed the reasons for the easy flotation of sulfide ores at high altitude with less collector dosage,and confirmed that the combined DO-pH regulation is beneficial to achieve more efficient flotation of pyrite. 展开更多
关键词 high altitude DISSOLVED-OXYGEN PYRITE FLOTATION OXIDATION
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A Stroke-Limitation AMD Control System with Variable Gain and Limited Area for High-Rise Buildings
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作者 Zuo-Hua Li Qing-Gui Wu +1 位作者 Jun Teng Chao-Jun Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期865-884,共20页
Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a ... Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a strokelimited AMD control system with a fixed limited area shortens the available AMD stroke and leads to significant control power.To solve this problem,the design approach with variable gain and limited area(VGLA)is proposed in this study.First,the boundary of variable-limited areas is calculated based on the real-time status of the moving mass.The variable gain(VG)expression at the variable limited area is deduced by considering the saturation of AMD stroke.Then,numerical simulations of a stroke-limited AMD control system with VGLA are conducted on a high-rise building structure.These numerical simulations show that the proposed approach has superior strokelimitation performance compared with a stroke-limited AMD control system with a fixed limited area.Finally,the proposed approach is validated through experiments on a four-story steel frame. 展开更多
关键词 high-rise buildings active control stroke limitations variable gain variable limited area
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Effects of Health Education with Problem-Based Learning Approaches on the Knowledge, Attitude, Practice and Coping Skills of Women with High-Risk Pregnancies in Plateau Areas
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作者 Ying Wu Suolang Sezhen +5 位作者 Renqing Yuzhen Hong Wei Zhijuan Zhan Baima Hongying Yuhong Zhang Lihong Liu 《Open Journal of Nursing》 2024年第5期192-199,共8页
Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approach... Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approaches on the knowledge, attitude, practice, and coping skills of women with high-risk pregnancies in this region. Methods: 76 high-risk pregnancy cases were enrolled at Tibet’s Linzhi People’s Hospital between September 2023 and April 2024. 30 patients admitted between September 2023 and December 2023 were selected as the control group and were performed with regular patient education. 46 patients admitted between January 2024 and April 2024 were selected as the observation group and were performed regular patient education with problem-based learning approaches. Two groups’ performance on their health knowledge, attitude, practice and coping skills before and after interventions were evaluated, and patient satisfaction were measured at the end of the study. Results: There was no statistical significance (P P P Conclusions: Health education with problem-based learning approaches is worth promoting as it can help high-risk pregnant women in plateau areas develop better health knowledge, attitude and practice and healthier coping skills. Also, it can improve patient sanctification. 展开更多
关键词 Plateau areas Patients with high-Risk Pregnancies Problem-Based Learning Health Education Health Knowledge Attitude and Practice Coping Skills
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Clinical efficacy of intradermal type Ⅰ collagen injections in treating skin photoaging in patients from high-altitude areas
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作者 Bin Yang Ao He +6 位作者 Bin-Bin Bu Gong Zhuo Qing-Zhu Zhou Jia-Hang He Liu Liu Wen-Li Huang Xian Zhao 《World Journal of Clinical Cases》 SCIE 2024年第16期2713-2721,共9页
BACKGROUND Photoaging,a result of chronic sun exposure,leads to skin damage and pigmentation changes.Traditional treatments may have limitations in high-altitude areas like Yunnan Province.Intradermal Col Ⅰ injection... BACKGROUND Photoaging,a result of chronic sun exposure,leads to skin damage and pigmentation changes.Traditional treatments may have limitations in high-altitude areas like Yunnan Province.Intradermal Col Ⅰ injections stimulate collagen production,potentially improving skin quality.This study aims to assess the efficacy and safety of this treatment for photoaging.AIM To evaluate the efficacy and safety of intradermal typeΙcollagen(ColΙ)injection for treating photoaging.METHODS This prospective,self-controlled study investigated the impact of intradermal injections of ColΙon skin photodamage in 20 patients from the Yunnan Province.Total six treatment sessions were conducted every 4 wk±3 d.Before and after each treatment,facial skin characteristics were quantified using a VISIA skin detector.Skin thickness data were assessed using the ultrasound probes of the Dermalab skin detector.The Face-Q scale was used for subjective evaluation of the treatment effect by the patients.RESULTS The skin thickness of the right cheek consistently increased after each treatment session compared with baseline.The skin thickness of the left cheek significantly increased after the third through sixth treatment sessions compared with baseline.The skin thickness of the right zygomatic region increased after the second to sixth treatment sessions,whereas that of the left zygomatic region showed a significant increase after the fourth through sixth treatment sessions.The skin thickness of both temporal regions significantly increased after the fifth and sixth treatment sessions compared with baseline(P<0.05).These findings were also supported by skin ultrasound images.The feature count for the red areas and wrinkle feature count decreased following the treatment(P<0.05).VISIA assessments also revealed a decrease in the red areas after treatment.The Face-QSatisfaction with Facial Appearance Overall and Face-Q-Satisfaction with Skin scores significantly increased after each treatment session.The overall appearance of the patients improved after treatment.CONCLUSION Intradermal ColΙinjection improves photoaging,with higher patient satisfaction and fewer adverse reactions,and could be an effective treatment method for populations residing in high-altitude areas. 展开更多
关键词 PHOTOAGING TypeΙcollagen Face-Q high-altitude area Skin photodamage Patient satisfaction
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Three‐dimensional(3D)‐printed MXene high‐voltage aqueous micro‐supercapacitors with ultrahigh areal energy density and low‐temperature tolerance
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作者 Yuanyuan Zhu Qingxiao Zhang +6 位作者 Jiaxin Ma Pratteek Das Liangzhu Zhang Hanqing Liu Sen Wang Hui Li Zhong‐Shuai Wu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期36-48,共13页
The rapid advancement in the miniaturization,integration,and intelligence of electronic devices has escalated the demand for customizable microsupercapacitors(MSCs)with high energy density.However,efficient microfabri... The rapid advancement in the miniaturization,integration,and intelligence of electronic devices has escalated the demand for customizable microsupercapacitors(MSCs)with high energy density.However,efficient microfabrication of safe and high‐energy MXene MSCs for integrating microelectronics remains a significant challenge due to the low voltage window in aqueous electrolytes(typically≤0.6 V)and limited areal mass loading of MXene microelectrodes.Here,we tackle these challenges by developing a highconcentration(18mol kg^(−1))“water‐in‐LiBr”(WiB)gel electrolyte for MXene symmetric MSCs(M‐SMSCs),demonstrating a record high voltage window of 1.8 V.Subsequently,additive‐free aqueous MXene ink with excellent rheological behavior is developed for three‐dimensional(3D)printing customizable all‐MXene microelectrodes on various substrates.Leveraging the synergy of a highvoltage WiB gel electrolyte and 3D‐printed microelectrodes,quasi‐solid‐state MSMSCs operating stably at 1.8 V are constructed,and achieve an ultrahigh areal energy density of 1772μWhcm^(−2) and excellent low‐temperature tolerance,with a long‐term operation at−40℃.Finally,by extending the 3D printing protocol,M‐SMSCs are integrated with humidity sensors on a single planar substrate,demonstrating their reliability in miniaturized integrated microsystems. 展开更多
关键词 3D printing aqueous electrolyte high voltage micro‐supercapacitors MXene
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Predictive value of intracranial high-density areas in neurological function
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作者 Zhi-Juan Lu Jin-Xing Lai +2 位作者 Jing-Ru Huang Shu-Hua Xie Zhao-Hui Lai 《World Journal of Psychiatry》 SCIE 2024年第7期1080-1086,共7页
BACKGROUND Intracranial high-density areas(HDAs)have attracted considerable attention for predicting clinical outcomes;however,whether HDAs predict worse neurological function and mental health remains controversial a... BACKGROUND Intracranial high-density areas(HDAs)have attracted considerable attention for predicting clinical outcomes;however,whether HDAs predict worse neurological function and mental health remains controversial and unclear,which requires further investigation.In this prospective study,96 patients with acute ischemic stroke(AIS)who accepted endovascular mechanical thrombectomy(EMT)were included.The enrolled patients underwent cranial computed tomography(CT)examination within 24 hours after EMT.Clinical data in terms of National Institutes of Health Stroke Scale(NIHSS),the 3-month modified Rankin Scale(mRS),self-rating depression scale(SDS),and self-rating anxiety scale(SAS)scores were collected and compared between patients with HDAs and non-HDAs and between patients with good and poor clinical prognosis.Compared to patients without HDAs,patients with HDAs presented severe neurological deficits(admission NIHSS score:18±3 vs 19±4),were more likely to have post-stroke disabilities(mRS<3:35%vs 62%),and suffered more severe depression(SDS score:58±16 vs 64±13)and anxiety disorder(SAS score:52±8 vs 59±10).Compared to patients with a good prognosis,patients with a poor prognosis presented severe neurological deficits(admission NIHSS score:17±4 vs 20±3),were more likely to have HDAs on CT images(64%vs 33%),and suffered more severe depression(SDS score:55±19 vs 65±11)and anxiety(SAS score:50±8 vs 58±12).Multivariate analysis revealed that HDAs were independent nega-tive prognostic factors.CONCLUSION In conclusion,HDAs on CT images predicted poor prognosis and severe depressive and anxiety symptoms in patients with AIS who underwent EMT. 展开更多
关键词 Acute ischemic stroke Endovascular mechanical thrombectomy high-density areas Depressive disorder Anxiety disorder
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Regional Brand and High-quality Development of Fruits in Ethnic Areas of the Yangtze River Economic Belt under the Greater Food Approach
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作者 Li GAO Jianjun ZHANG +2 位作者 Yuanpeng SUN Zhiyang LIU Zhiguo SUN 《Asian Agricultural Research》 2024年第3期1-7,共7页
Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.T... Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.This paper introduces the characteristics of fruit industry in 16 autonomous prefectures and 47 autonomous counties under the jurisdiction of the Yangtze River Economic Belt.It studies the intellectual property resources of brand marks from the aspects of geographical indications,collective trademarks,certification trademarks,well-known trademarks in China and national design patents,and analyzes the main problems of brand and high-quality development of fruit industry in these ethnic autonomous areas.Finally,it puts forward some strategies,such as improving the protection of intellectual property rights of geographical indications,using intellectual property rights of brand signs,building modern seed industry upgrading project,drawing lessons from the experience of thousand villages demonstration project,ensuring that large-scale poverty does not occur,and building a diversified food supply system. 展开更多
关键词 GREATER FOOD APPROACH Fruit industry Regional brand The Yangtze River Economic Belt ETHNIC areas
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Promoting High-quality Development of Grain and Oil in Ethnic Areas of the Yangtze River Economic Belt from the Perspective of Agricultural Power
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作者 Li GAO Jianjun ZHANG +2 位作者 Yuanpeng SUN Zhiyang LIU Zhiguo SUN 《Asian Agricultural Research》 2024年第2期1-7,11,共8页
Accelerating the construction of agricultural power,further promoting the high-quality development of the Yangtze River Economic Belt,and better supporting and serving Chinese-style modernization are the key issues at... Accelerating the construction of agricultural power,further promoting the high-quality development of the Yangtze River Economic Belt,and better supporting and serving Chinese-style modernization are the key issues at present.This paper first introduces the Yangtze River Economic Belt and its ethnic areas,and studies the characteristics of the grain and oil industry in the ethnic autonomous areas of the economic belt,as well as the current situation of various types of intellectual property resources,such as industrial cultural heritage,scientific and tech-nological innovation,and brand marking intellectual property.Besides,it analyzes the main problems in the high-quality development of grain and oil in the Yangtze River Economic Belt ethnic areas.Finally,it comes up with recommendations,including protecting the intellectual prop-erty rights of cultural heritage in the field of grain and oil,leading the inheritance and development of excellent traditional Chinese culture,use scientific and technological innovation intellectual property rights to promote the innovation-driven development strategy of the grain and oil in-dustry,and providing counterpart assistance to ethnic autonomous areas in the Yangtze River Economic Belt to further promote the high-quality development of the Yangtze River Economic Belt. 展开更多
关键词 The Yangtze River Economic Belt Ethnic areas Grain and oil Intellectual property Agricultural power
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Seismic Reduction and Isolation Design Strategies for Bridges in High-Intensity Earthquake Areas
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作者 Shengtang Wang 《Journal of Architectural Research and Development》 2024年第1期68-74,共7页
High-intensity earthquakes can cause severe damage to bridges,buildings,and ground surfaces,as well as disrupt human activities.Such earthquakes can create long-distance,high-intensity surface movements that negativel... High-intensity earthquakes can cause severe damage to bridges,buildings,and ground surfaces,as well as disrupt human activities.Such earthquakes can create long-distance,high-intensity surface movements that negatively impact bridge structures.This article delves into the seismic reduction and isolation design strategies for bridges in high-intensity earthquake areas.It analyzes various seismic reduction and isolation technologies and provides case studies to help relevant units understand the design strategies of these technologies.The results of this article can be used as a guideline to effectively enhance the seismic performance of bridges in high-intensity earthquake areas. 展开更多
关键词 high-intensity earthquake areas Rubber isolation Seismic reinforcement technology
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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Screening of Wheat Cultivars for High Temperature Resistance to Stripe Rust from Wheat Resources in Huanghuai Growth Area 被引量:4
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作者 杨炜迪 陈宏灏 王美南 《Agricultural Science & Technology》 CAS 2008年第3期89-91,共3页
[Objective] The study aimed to screen wheat cultivars with high temperature resistance to stripe rust from the wheat resources in Huanghuai growth area. [Method] Seedlings of 165 wheat cultivars from Huanghuai growth ... [Objective] The study aimed to screen wheat cultivars with high temperature resistance to stripe rust from the wheat resources in Huanghuai growth area. [Method] Seedlings of 165 wheat cultivars from Huanghuai growth area were identified by wheat stripe rust under high temperature; then the wheat cultivars showing stripe rust at seedling stage were further used to identify the same resistance in field. [Results] 13 cultivars were proved to be stripe rust resistant under high temperature, and the expression stages of stripe rust in the 13 cultivars were revealed. The field identification results confirmed the identification results at seedling stage via inoculation of mixed stripe rust of physiological races. The stripe resistances of wheat cultivars were also proved to be non-race-specific. [Conclusion] Wheat resources in Huanghuai growth area are abundant in wheat cultivars with high temperature resistance to stripe rust. 展开更多
关键词 WHEAT high temperature disease resistance STRIPE RUST
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Influence of Global Warming on High-active Agricultural Development in Chaoyang Area 被引量:1
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作者 周广学 李普庆 周晓东 《Meteorological and Environmental Research》 CAS 2010年第3期42-44,共3页
The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in... The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in protective field,gross agricultural output value.The results showed that climate warming had a very significant positive effect on the development of high-active agriculture in Chaoyang. 展开更多
关键词 Chaoyang area INFLUENCE high-active agriculture China
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Low temperature solid-phase sintering of sintered metal fibrous media with high specific surface area 被引量:4
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作者 唐彪 汤勇 +3 位作者 周蕤 陆龙生 刘彬 屈修明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1755-1760,共6页
A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting proc... A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting process were first plated with a coarse copper coating layer by electroless plating process.A low-temperature sintering process was then completed at about 800 °C for 1 h under the protection of hydrogen atmosphere.The results show that a novel SMFM with complex surface morphology and high specific surface area(0.2 m2/g) can be obtained in this way.The effect of sintering temperature on the surface morphology and specific surface area of SMFM was studied by means of scanning electron microscopy and Brunauer-Emmett-Teller.The damage of micro-structure during the sintering process mainly contributed to the loss of specific surface area of SMFM and the optimal sintering temperature was 800 °C. 展开更多
关键词 sintered metal fibrous media low temperature solid-phase sintering electroless copper plating surface morphology specific surface area
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Satellite and high altitude platform-based inter-vehicle communications in vast and desolate areas 被引量:1
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作者 林元乖 王琳 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期135-139,共5页
In order to solve the problem of inter-vehicle communication (IVC) in vast and desolate areas such as the desert and the Gobi, two vehicle network models are proposed. One is based on satellite communication and the... In order to solve the problem of inter-vehicle communication (IVC) in vast and desolate areas such as the desert and the Gobi, two vehicle network models are proposed. One is based on satellite communication and the other is based on high altitude platform ( HAP ) communication. The system outline and networking modes of the two models are described. In the satellite communication based model, all the vehicles are equipped with vehicle-bone satellite communication on the move terminals and the communication signals between vehicles are forwarded by satellite. In the high altitude platform-based model, the HAPs are equipped with base station facilities to form aerial base stations, and vehicles can communicate with each other via common terrestrial mobile communication devices. Some key parameters such as path loss, link loss and system capacity are also computed. The analysis shows that both the two models can satisfy the requirement of IVC in the descriptive environment. 展开更多
关键词 inter-vehicle communication satellite communication high altitude platform communication terrestrial mobile communication device system capacity
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Cultivation Techniques for High-yield Corn in a Karst Area of Southwest Guizhou
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作者 郭银萍 王永树 黄蔚 《Agricultural Science & Technology》 CAS 2014年第8期1339-1341,共3页
The cultivation techniques for high-yield corn in a karst area of southwest Guizhou were elaborated in this research from the respects of choosing farmland, preparing farmland, picking good seeds, timely sowing, ratio... The cultivation techniques for high-yield corn in a karst area of southwest Guizhou were elaborated in this research from the respects of choosing farmland, preparing farmland, picking good seeds, timely sowing, rational close planting, im-proving the quality of planting, mulching, scientific fertilization, field management, timely harvest, etc. we hoped to provide a reference for the realization of high-effi-ciency corn planting in mountain areas. 展开更多
关键词 Karst area CORN high yield Cultivation technique
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Cultivation of Black Fungus under Forest in Middle-high Altitude Areas
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作者 袁长波 徐延熙 +5 位作者 王艳芹 姚利 付龙云 田叶 李瑞琴 曹德宾 《Agricultural Science & Technology》 CAS 2016年第10期2358-2361,共4页
[Objective] The study was to solve the contradiction between fungus and forest during the production of black fungi, and to obtain relatively high economic benefits and ecological benefits. [Method] Black fungi were c... [Objective] The study was to solve the contradiction between fungus and forest during the production of black fungi, and to obtain relatively high economic benefits and ecological benefits. [Method] Black fungi were cultivated in forest with middle-high altitude of 500-1 600 m. The germination time of fungus stick, germination days of buds, growth days of fruiting body, commodity exterior, marketing effect and biological efficiency of black fungi were investigated. [Result] Compared with traditional cultivation, black fungus products cultivated under forest had the taste and flavor of wild black fungus. Fungus chaff wastage was directly decomposed by the roots in forest land, improving the soil structure of forest land. The need of moisture retention and the frequent access of administrative staff reduced the probability of forest fire occurrence. [Conclusion] Cultivation of black fungus under forest saves more than 70% fixed-asset investment on fungus shed, and the biological efficiency reached 12.2%. 展开更多
关键词 Forest area in middle-high altitude Under forest Black Fungus
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Acute lesions of primary visual cortical areas in adult cats inactivate responses of neurons in higher visual cortices 被引量:1
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作者 张辉 孟建军 +3 位作者 王珂 刘瑞龙 奚敏敏 华田苗 《Zoological Research》 CAS CSCD 北大核心 2012年第2期218-224,共7页
Psychophysical studies suggest that lateral extrastriate visual cortical areas in cats may mediate the sparing of vision largely by network reorganization following lesions of early visual cortical areas. To date, how... Psychophysical studies suggest that lateral extrastriate visual cortical areas in cats may mediate the sparing of vision largely by network reorganization following lesions of early visual cortical areas. To date, however, there is little direct physiological evidence to support this hypothesis. Using in vivo single-anit recording techniques, we examined the response of neurons in areas 19, 21, and 20 to different types of visual stimulation in cats with or without acute bilateral lesions in areas 17 and 18. Our results showed that, relative to the controls, acute lesions inactivated the response of 99.3% of neurons to moving gratings and 93% of neurons to flickering square stimuli'in areas 19, 21, and 20. These results indicated that acute lesions of primary visual areas in adult eats may impair most visual abilities. Sparing of vision in cats with neonatal lesions in early visual cortical areas may result largely from a postoperative reorganization of visual pathways from subcortical nucleus to extrastriate visual cortical areas. 展开更多
关键词 Acute lesion Primary visual cortical areas Neuronal response areas 19 21 and 20
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Characteristics and origin of abnormally high porosity zones in buried Paleogene clastic reservoirs in the Shengtuo area, Dongying Sag, East China 被引量:24
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作者 Cao Yingchang Yuan Guanghui +5 位作者 Li Xiaoyan Wang Yanzhong Xi Kelai Wang Xiaoming Jia Zhenzhen Yang Tian 《Petroleum Science》 SCIE CAS CSCD 2014年第3期346-362,共17页
There are three abnormally high porosity zones developed in buried Paleogene nearshore subaqueous fan and sublacustrine fan clastic'reservoirs at 2,800-3,200 m, 3,250-3,700 m and 3,900- 4,400 m, respectively, within ... There are three abnormally high porosity zones developed in buried Paleogene nearshore subaqueous fan and sublacustrine fan clastic'reservoirs at 2,800-3,200 m, 3,250-3,700 m and 3,900- 4,400 m, respectively, within the Shengtuo area of the Dongying Sag. Here the porosity of reservoirs buried deeper than 4,000 m can still be greater than 20%. Investigation of these three abnormally high porosity (AHP) zones in the 3rd to 4th member of the Paleogene Shahejie Formation in the Shengtuo area was carried out with utilization of core observation, thin section identification, SEM observation, image analysis, core physical property testing and other technical methods. The results show that, the AHP zones in 2,800-3,200 m and 3,250-3,700 m are visible pores primary AHP zones dominated by significant primary intergranular pores (more than 50% of the total porosity), while secondary pores and micropores in authigenic clays may develop in some reservoirs. AHP reservoirs in the AHP zone of 3,900-4,400 m are dominated by micropores in matrix, visible pores are mainly grain dissolution pores but with low absolute content (〈 1%), so this zone belongs to the micropores primary AHP zone. The genesis of the three AHP zones was studied to distinguish between porosity enhancement and porosity preservation. Our research shows that, in deeply buried clastic reservoirs in the Shengtuo area, mineral dissolution occurred in a relatively closed diagenetic system with high temperature and high salinity. Reservoir rocks underwent extensive feldspar dissolution, while detrital carbonate grains and carbonate cements show no evidence of extensive dissolution. Although significant feldspar dissolution pores developed, feldspar dissolution enhanced porosity only a little due to the precipitation of almost isovolumetric dissolution products in the nearby primary intergranular pores in forms of authigenic clays and quartz cements. Net enhanced porosity originating from feldspar dissolution is generally less than 0.25%. Thus, the subsurface dissolution has little impact on the mid-deep buried high porosity reservoirs. Reservoirs in braided channels of middle fans in sublacustrine fans and reservoirs in the middle-front of fan bodies of nearshore subaqueous fans provide the basis for the development of AHP zones. The shallow development of fluid overpressure and early hydrocarbon emplacement have effectively retarded compaction and carbonate cementation, so that the high porosity in the superficial layers is preserved in the mid-deep layers. These are the main controlling factors in the development of AHP zones. 展开更多
关键词 Dongying Sag Shengmo area abnormally high porosity zone pores GENESIS
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