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Source-Load Coordinated Optimal Scheduling Considering the High Energy Load of Electrofused Magnesium and Wind Power Uncertainty
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作者 Juan Li Tingting Xu +3 位作者 Yi Gu Chuang Liu Guiping Zhou Guoliang Bian 《Energy Engineering》 EI 2024年第10期2777-2795,共19页
In fossil energy pollution is serious and the“double carbon”goal is being promoted,as a symbol of fresh energy in the electrical system,solar and wind power have an increasing installed capacity,only conventional un... In fossil energy pollution is serious and the“double carbon”goal is being promoted,as a symbol of fresh energy in the electrical system,solar and wind power have an increasing installed capacity,only conventional units obviously can not solve the new energy as the main body of the scheduling problem.To enhance the systemscheduling ability,based on the participation of thermal power units,incorporate the high energy-carrying load of electro-melting magnesiuminto the regulation object,and consider the effects on the wind unpredictability of the power.Firstly,the operating characteristics of high energy load and wind power are analyzed,and the principle of the participation of electrofusedmagnesiumhigh energy-carrying loads in the elimination of obstructedwind power is studied.Second,a two-layer optimization model is suggested,with the objective function being the largest amount of wind power consumed and the lowest possible cost of system operation.In the upper model,the high energy-carrying load regulates the blocked wind power,and in the lower model,the second-order cone approximation algorithm is used to solve the optimizationmodelwithwind power uncertainty,so that a two-layer optimizationmodel that takes into account the regulation of the high energy-carrying load of the electrofused magnesium and the uncertainty of the wind power is established.Finally,the model is solved using Gurobi,and the results of the simulation demonstrate that the suggested model may successfully lower wind abandonment,lower system operation costs,increase the accuracy of day-ahead scheduling,and lower the final product error of the thermal electricity unit. 展开更多
关键词 high energy load of electrofused magnesium wind energy consumption thermal power unit wind power uncertainty two-layer optimization
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High Resolution ID-TIMS Redefines the Distribution and Age of the Main Mesozoic Lacustrine Hydrocarbon Source Rocks in the Ordos Basin,China 被引量:3
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作者 CUI Jingwei ZHU Rukai +2 位作者 ZHANG Zhongyi Jahandar RAMEZANI LI Yang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期581-588,共8页
Using high-precision zircon U-Pb ID-TIMS geochronology,tuffs from the Chang 9 shale and the Chang 7 shale were dated.The tuff in the Chang 9 shale is 241.47±0.17 Ma,which falls between the top tuff age of 241.06&... Using high-precision zircon U-Pb ID-TIMS geochronology,tuffs from the Chang 9 shale and the Chang 7 shale were dated.The tuff in the Chang 9 shale is 241.47±0.17 Ma,which falls between the top tuff age of 241.06±0.12 Ma and the bottom tuff age of 241.558±0.093 Ma in the Chang 7 shale.These reveal that the Chang 9 and Chang 7 shales are contemporaneous,belonging to the Ladinian stage of the Middle Triassic.This insight expands the region of the main source rock of Chang 7 to the northeast and will inform the search for the deep Chang 9 shale petroleum system,increasing the scope for exploring the Chang 7 shale system in northern Shaanxi.The research results clarify the relationship between the two sets of shale in the Yanchang Formation and redefine the distribution range of the Chang 7 shale in the Ordos Basin.At the same time,it shows that there is a cross-layer problem in the stratigraphic division of the Yanchang Formation in different regions,the high-precision U-Pb dating technology providing a reference for the fine stratigraphic correlation of other continental basins in the world. 展开更多
关键词 ID-TIMS high precision age redefining distribution Chang 7 shale Chang 9 shale Ordos Basin
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The age at first consumption of forage in calves and its effect on growth and rumination in the short‑and long‑term 被引量:2
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作者 Jianxin Xiao Tianyu Chen +10 位作者 Rong Peng Gibson Maswayi Alugongo Hui Yang Muhammad Zahoor Khan Shuai Liu Yulin Ma Jingjun Wang Wei Wang Yajing Wang Shengli Li Zhijun Cao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期2143-2157,共15页
Background Previous investigations into the effect of dietary forage on calf performance have been inconsistent,and there is a paucity of information exploring the effect of age on the growth performance and ruminatio... Background Previous investigations into the effect of dietary forage on calf performance have been inconsistent,and there is a paucity of information exploring the effect of age on the growth performance and rumination of calves.Eighty-four female Holstein calves(41.5±4.2 kg)were enrolled at birth,a subset of the calves were fed calf starter only(CON,n=21)while the rest(n=63)were classified into three treatment groups:the early(EHAY,n=26,5.1±0.8 d),the middle(MHAY,n=21,7.9±0.8 d)and the late(LHAY,n=16,12.1±1.4 d)hay consumers.The short-term effect of the age at first forage consump-tion(AFF)on calves’feed intake was monitored until d 84.In addition,the long-term effects of AFF on body weight,structural growth and rumination behavior were recorded until d 196.Rumen samples were collected on d 1,7,35,84 and 196 to ana-lyze the rumen fermentation,while fecal samples were collected from d 78 to 84 to estimate digestibility parameters.Results Treatment had no effect on feed intake.While,the EHAY calves tended to have lower BW and ADG compared to LHAY and CON calves.Several total-tract apparent digestibility parameters and digestible nutrients intake were significantly lower in EHAY calves compared with CON and LHAY calves.Calves in the EHAY group tended to begin ruminating ealier,while CON calves were the latest(12.3 vs.15.5 days of age).A treatment and time interaction was present for rumination time due to greater rumination in calves consuming hay compared to CON calves in week 10 to 12,the differences in rumination disappeared afterwards,no long-lasting significant differences in the rumina-tion and rumen fermentation parameters were found between treatments.Conclusions In conclusion,this study showed that hay consumption earlier in life(in the first week,around 5 days of life)could negatively affect the growth of the calf in the short and long term.Compared to consuming hay from the second week(around 12 days of life)or feeding concentrate only without hay,starting to consume hay from the first week could compromise nutrient digestibility and digestible nutrient intake independent of developing rumination behaviour and rumen fermentation. 展开更多
关键词 age at first forage consumption Dairy calf GROWTH Nutrient digestibility Rumen fermentation RUMinATION
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The Influence of Internet Economy on High School Students’ Consumption Concept
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作者 Anqi Xiang 《Journal of Finance Research》 2020年第2期8-11,共4页
With the rapid development of Internet technology,the Internet economy has gradually penetrated into every aspect of people’s life.The group of high school students has increasingly become an important part of the In... With the rapid development of Internet technology,the Internet economy has gradually penetrated into every aspect of people’s life.The group of high school students has increasingly become an important part of the Internet consumption market,and its consumption concept is also deeply influenced by the Internet economy.Based on the analysis of the development status of the Internet economy and the characteristics of high school students’consumption concepts,this article analyzes the double impact of the Internet economy on high school students’consumption concepts.On this basis,it expounds how to guide high school students to form the correct consumption concepts under the Internet economy from the three dimensions of school,family and individual. 展开更多
关键词 internet economy high school students consumption concept IMPACT
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Study of High Efficiency Membrane Pilot Test for Membrane Design Optimisation in Order to Reduce the Electrical Consumption
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作者 Federico Antonio Leon Alejandro Ramos 《Journal of Energy and Power Engineering》 2016年第10期628-633,共6页
Regarding the studies of other authors about energy performance of a reverse osmosis desalination plant operating with variable pressure; about desalination efficiency in their different recent articles, we continued ... Regarding the studies of other authors about energy performance of a reverse osmosis desalination plant operating with variable pressure; about desalination efficiency in their different recent articles, we continued working in this way researching in a real seawater reverse osmosis plant following the items below. The objectives of this test are to get the minimum electrical consumption and energy costs for the operation of a sea water desalination plant using membranes. We need to compare the performance of the different membranes manufacturer's and to determine, under this new thermal scenario, the optimal configuration to get the water quality and quantity needs with the minimum energy consumption. 展开更多
关键词 Minimum energy consumption energetic efficiency high efficiency membrane energy costs.
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Differential Effects of Voluntary Ethanol Consumption on Dopamine Output in the Nucleus Accumbens Shell of Roman High- and Low-Avoidance Rats: A Behavioral and Brain Microdialysis Study
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作者 Maria G. Corda Giovanna Piras +1 位作者 Maria A. Piludu Osvaldo Giorgi 《World Journal of Neuroscience》 2014年第3期279-292,共14页
The Roman high(RHA) and low-Avoidance (RLA) rats were selectively bred for rapid vs poor acquisition of two-way active avoidance behavior. These lines differ in numerous behavioral traits, with RLA rats being more fea... The Roman high(RHA) and low-Avoidance (RLA) rats were selectively bred for rapid vs poor acquisition of two-way active avoidance behavior. These lines differ in numerous behavioral traits, with RLA rats being more fearful/anxious than RHA rats, and the latter being novelty-seekers and showing larger intake of, and preference for, addictive substances including ethanol (ETH). Moreover, several differences in central dopaminergic, serotonergic, and GABAergic functions have been reported in these two lines. Since those neural systems are involved in the regulation of ETH consumption, it was considered of interest to investigate: 1) the differences in ETH intake and preference between RHA and RLA rats, 2) the effects of ETH on DA release in the shell of the nucleus accumbens (AcbSh) using brain microdialysis. ETH solutions of increasing concentrations (2% - 10%) were presented on alternate days in a free choice with water. To examine ETH intake and preference stability, animals were subsequently switched to daily presentations of 10% ETH for 10 consecutive days. RHA rats consumed significantly larger amounts of ETH and displayed higher ETH preference than did RLA rats throughout the acquisition and maintenance phases. Following chronic exposure to ETH the animals were habituated to a restricted access to ETH schedule (2% ETH, 2 h per day × 4 days) before surgical implantation of a dialysis probe in the AcbSh. Under these experimental conditions, voluntary ETH intake (2%, 1 h, p.o.) produced a significant increase in accumbal DA output in RHA rats but not in their RLA counterparts. Finally, the i.p. administration of ETH (0.25 g/kg) to na?ve Roman rats produced a significant increment in accumbal DA output only in RHA rats. These results indicate that the mesolimbic dopaminergic system of RHA rats is more responsive to the effects of ETH than that of RLA rats. 展开更多
关键词 ROMAN high- and Low-Avoidance RATS VOLUNTARY Ethanol consumption Mesolimbic Dopaminergic System Nucleus Accumbens Shell Novelty-Seeking Behavior
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Decrement of Sugar Consumption in Rice Young Panicle Under High Temperature Aggravates Spikelet Number Reduction 被引量:8
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作者 WANG Yaliang ZHANG Yikai +9 位作者 SHI Qinghua CHEN Huizhe XIANG Jing HU Guohui CHEN Yanhua WANG Xiaodan WANG Junke YI Zihao ZHU Defeng ZHANG Yuping 《Rice science》 SCIE CSCD 2020年第1期44-55,共12页
Two rice genotypes Huanghuazhan(HHZ, heat-resistant) and IR36(heat-susceptible) were subjected to high-temperature(HT, 40℃) and normal-temperature(NT, 32℃) treatments at the spikelet differentiation stage. HT treatm... Two rice genotypes Huanghuazhan(HHZ, heat-resistant) and IR36(heat-susceptible) were subjected to high-temperature(HT, 40℃) and normal-temperature(NT, 32℃) treatments at the spikelet differentiation stage. HT treatment inhibited spikelet differentiation, aggravated spikelet degeneration, reduced spikelet size, and disordered carbohydrate allocation. Meanwhile, HT treatment increased nonstructural carbohydrate content in leaves, but decreased that in stems and young panicles, and the same tendencies of sucrose and starch contents were observed in leaves and stem. However, HT treatment significantly increased the sucrose content and sharply decreased the glucose and fructose contents in young panicles. Lower activity levels of soluble acid invertase(EC3.2.1.26) and sucrose synthase(EC2.4.1.13) were observed under HT treatment. Moreover, HT treatment reduced the activities of key enzymes associated with glycolysis and the tricarboxylic acid cycle, which indicated sucrose consumption was inhibited in young panicles under HT treatment. Exogenous glucose and fructose applied under HT treatment increased the spikelet number more than exogenous sucrose. In conclusion, the results demonstrated that the reduction of spikelet number under high temperature was more affected by the decrease in sugar consumption than the blocking of sucrose transport. The impairment of sucrose hydrolysis was the main reason for the inhibition of sugar utilization. 展开更多
关键词 RICE high temperature panicle development spikelet number carbohydrate allocation sugar consumption
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Effect of seedling age and water depth on morphological and physiological aspects of transplanted rice under high temperature 被引量:4
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作者 KHAKWANI Abdul Aziz SHIRAISHI Masaaki +3 位作者 ZUBAIR Muhammad BALOCH Mohammad Safdar NAVEED Khalid AWAN Inayatullah 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第5期389-395,共7页
To study the effect of high temperature, rice seedlings 20, 30, 40 and 50 d were kept at 5, 10, 15 and 20 cm water depth in a water pool. Meteorological findings indicated that water temperature varied up to 10 cm but... To study the effect of high temperature, rice seedlings 20, 30, 40 and 50 d were kept at 5, 10, 15 and 20 cm water depth in a water pool. Meteorological findings indicated that water temperature varied up to 10 cm but became stable below this depth. Deep water inflicted higher tiller mortality, minimal increase in dry weight of aerial parts and leaf area, decrease in root length, and decrease in root dry weight especially at 20 cm water depth and produced an unbalanced T/R ratio (top versus root dry weight). However, deep water tended to increase plant length. These parameters, however, excel in shallow water. Older seedlings, with the exception of root dry weight, could not perform well compared to young seedlings in all physiological and morphological aspects. The study revealed that seedlings, particularly young ones, stand well in shallow water and can cope with high temperature. 展开更多
关键词 RICE high temperature Seedling age Water depth
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Influences of Seasonal Freezing and Thawing on Soil Water-stable Aggregates in Orchard in High Cold Region,Northeast China 被引量:3
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作者 LIANG Yunjiang DENG Xu +4 位作者 SONG Tao CHEN Guoshuang WANG Yuemei ZHANG Qing LU Xinrui 《Chinese Geographical Science》 SCIE CSCD 2021年第2期234-247,共14页
Soil aggregate stability,as an important indicator of soil functions,may be affected by seasonal freezing and thawing(SFT)and land use in high cold and wet regions.Therefore,comprehensive understanding the effects of ... Soil aggregate stability,as an important indicator of soil functions,may be affected by seasonal freezing and thawing(SFT)and land use in high cold and wet regions.Therefore,comprehensive understanding the effects of SFT on aggregate stability in orchards during winter and spring is crucial to develop appropriate management strategies that can effectively alleviate the degradation of soil quality to ensure sustainable development of orchard ecosystems.To determine the mechanism of degradation in orchard soil quality,the effects of SFT on the stability of water-stable aggregates were examined in apple-pear orchards(Pyrus ussuriensis var.ovoidea)of four different ages(11,25,40,and 63 yr)on 0 to 5%slopes before freezing and after thawing from October 2015 to June 2016 in Longjing City,Yanbian Prefecture,Northeast China,involving a comparison of planted versus adjacent uncultivated lands(control).Soil samples were collected to investigate water-stable aggregate stability in three incremental soil layers(0–20,20–40 and 40–60 cm).In the same samples,iron oxide,organic matter,and clay contents of the soil were also determined.Results showed that the destructive influences of SFT on water-stable aggregates were more pronounced with the increased orchards ages,and SFT exerted severe effects on water-stable aggregates of older orchards(40 and 63 yr)than juvenile orchards.Undergoing SFT,the soil instability index and the percentage of aggregate destruction increased by mean 0.15 mm and 1.86%,the degree of aggregation decreased by mean 1.32%,and the erosion resistance weakened,which consequently led to aggregate stability decreased.In addition,soil free,amorphous,and crystalline iron oxide as well as soil organic matter and clay contents are all important factors affecting the stability of water-stable aggregates,and their changes in their contents were consistent with those in the stability of water-stable aggregates.The results of this study suggest that long-term planting fruit trees can exacerbate the damaging effects of SFT on aggregate stability and further soil erosion increases and nutrient losses in an orchard,which hider sustainable use of soil and the productivity orchards. 展开更多
关键词 water-stable aggregates orchard age apple-pear orchard soil seasonal freezing and thawing soil degradation high cold region
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The Sm-Nd Geochronology of the High Pressure Basic Granulite in Laixi, Eastern Shandong 被引量:4
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作者 Li Yonggang,Zhai Mingguo,Liu Wenjun,Guo Jinghui and Li Tiesheng (Institute of Geology, Chinese Academy of Sciences, Beijing 100029 China) 《Global Geology》 1999年第1期34-40,共7页
A high pressure basic granulite ultramafic rock belt, which is about 200km long and trends toward NE, occurs in the late Archaean orthogneiss in Laixi Laiyang Qixia area, eastern Shangdong. This belt is located east t... A high pressure basic granulite ultramafic rock belt, which is about 200km long and trends toward NE, occurs in the late Archaean orthogneiss in Laixi Laiyang Qixia area, eastern Shangdong. This belt is located east to the Su Lu UHPM terrane and west to the Archaean rocks of the North China craton, therefore, its geological situation and implication for collision between the North China plate and the Yangtze plate is very important. The analyzed sample of high pressure basic granulite has decreasing pressure metamorphic texture. The mineral assemblage of retrograde metamorphism is of granulite facies. The sample yields an internal mineral whole rock Sm Nd isochron age of 1725Ma. The T(DM) age of whole rock is 2788Ma. These data are very similar to those of high pressure basic granulites in Northern China craton. Considering the petrological and geochemical characteristics and isotopic ages, the high pressure granulite ultramafic rock belt in eastern Shandong is suggested to belong to the North China craton and to be of the early Precambrian lower crust. Their lifting from the lower crustal level is related to collision between the North China plate and the Yangtze plate. 展开更多
关键词 ISOTOPIC geochronolgy SM-ND ISOTOPIC age high PRESSURE basic GRANULITE EASTERN SHANDONG
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Effects of curing age on compressive and tensile stress-strain behaviors of ecological high ductility cementitious composites 被引量:1
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作者 Chai Lijuan Guo Liping +1 位作者 Chen Bo Cao Yuanzhang 《Journal of Southeast University(English Edition)》 EI CAS 2020年第1期73-80,共8页
To obtain the design parameters of the structure made by ecological high ductility cementitious composites(Eco-HDCC),the effects of curing age on the compressive and tensile stress-strain relationships were studied.Th... To obtain the design parameters of the structure made by ecological high ductility cementitious composites(Eco-HDCC),the effects of curing age on the compressive and tensile stress-strain relationships were studied.The reaction degree of fly ash,non-evaporable water content and the pH value in pore solution were calculated to reveal the mechanical property.The results indicate that as the curing age increases,the peak compressive strength,peak compressive strain and ultimate tensile strength of Eco-HDCC increase.However,the ultimate compressive strain and ultimate tensile strain of Eco-HDCC decrease with the increase in curing age.Besides,as the curing age increases,the reaction degree of fly ash and non-evaporable water content in Eco-HDCC increase,while the pH value in the pore solution of Eco-HDCC decreases.Finally,the simplified compressive and tensile stress-strain constitutive relationship models of Eco-HDCC with a curing age of 28 d were suggested for the structure design safety. 展开更多
关键词 ecological high ductility cementitious composites(Eco-HDCC) compressive stress-strain behavior tensile stress-strain behavior curing age reaction degree non-evaporable water content pH value in pore solution
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Stem sap flow of Haloxylon ammodendron at different ages and its response to physical factors in the Minqin oasis-desert transition zone, China
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作者 QIANG Yuquan ZHANG Jinchun +2 位作者 XU Xianying LIU Hujun DUAN Xiaofeng 《Journal of Arid Land》 SCIE CSCD 2023年第7期842-857,共16页
Haloxylon ammodendron, with its tolerance of drought, high temperature, and salt alkali conditions, is one of the main sand-fixing plant species in the oasis-desert transition zone in China. This study used the TDP30(... Haloxylon ammodendron, with its tolerance of drought, high temperature, and salt alkali conditions, is one of the main sand-fixing plant species in the oasis-desert transition zone in China. This study used the TDP30(where TDP is the thermal dissipation probe) to measure hourly and daily variations in the stem sap flow velocity of H. ammodendron at three age-classes(10, 15, and 20 years old,which were denoted as H10, H15, and H20, respectively) in the Minqin oasis-desert transition zone,China, from May through October 2020. By simultaneously monitoring temperature, relative humidity,photosynthetically active radiation, wind speed, net radiation, rainfall, and soil moisture in this region, we comprehensively investigated the stem sap flow velocity of different-aged H. ammodendron plants(H10,H15, and H20) and revealed its response to physical factors. The results showed that, on sunny days, the hourly variation curves of the stem sap flow velocity of H. ammodendron plants at the three age-classes were mainly unimodal. In addition, the stem sap flow velocity of H. ammodendron plants decreased significantly from September to October, which also delayed its peak time of hourly variation. On rainy days, the stem sap flow velocity of H. ammodendron plants was multimodal and significantly lower than that on sunny days.Average daily water consumption of H. ammodendron plants at H10, H15, and H20 was 1.98, 2.82, and 1.91kg/d, respectively. Temperature was the key factor affecting the stem sap flow velocity of H. ammodendron at all age-classes. Net radiation was the critical factor influencing the stem sap flow velocity of H.ammodendron at H10 and H15;however, for that at H20, it was vapor pressure deficit. The stem sap flow velocity of H. ammodendron was highly significantly correlated with soil moisture at the soil depths of 50and 100 cm, and the correlation was strengthened with increasing stand age. Altogether, our results revealed the dynamic changes of the stem sap flow velocity in different-aged H. ammodendron forest stands and its response mechanism to local physical factors, which provided a theoretical basis for the construction of new protective forests as well as the restoration and protection of existing ones in this region and other similar arid regions in the world. 展开更多
关键词 Haloxylon ammodendron stem sap flow stand age soil moisture water consumption Minqin oasis-desert transition zone
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The Influence of Sea Sprays on Drag Coefficient at High Wind Speed
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作者 SHI Hongyuan LI Qingjie +4 位作者 WANG Zhaowei ZHANG Xuri LI Huaqing XING Hao ZHANG Kuncheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期21-27,共7页
Field and laboratory observations indicate that the variation of drag coefficient with wind speed at high winds is different from that under low-to-moderate winds.By taking the effects of wave development and sea spra... Field and laboratory observations indicate that the variation of drag coefficient with wind speed at high winds is different from that under low-to-moderate winds.By taking the effects of wave development and sea spray into account,a new parameterization of drag coefficient applicable from low to extreme winds is proposed.It is shown that,under low-to-moderate wind conditions so that the sea spray effects could be neglected,the nondimensional aerodynamic roughness first increases and then decreases with the increasing wave age;whereas under high wind conditions,the drag coefficient decreases with the increasing wind speed due to the modification of the logarithmic wind profile by the effect of sea spray droplets produced by bursting bubbles or wind tearing breaking wave crests.The drag coefficients and sea surface aerodynamic roughnesses reach their maximum values vary under different wave developments.Correspondingly,the reduction of drag coefficient under high winds reduces the increasing rate of friction velocity with increasing wind speed. 展开更多
关键词 sea spray wave age drag coefficient high wind speed
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Infertility in Men with Varicocele: The Role of Age, Smoking and Alcohol Intake
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作者 Luca Coppeta Anna Neri +4 位作者 Maria Nicotra Vincenzo Gentile Claudio Spina Adalgisa Pietropolli Fulvia Gloria-Bottini 《Health》 2020年第3期231-239,共9页
Previous studies have focused on the damaging effects of smoking and alcohol on sperm parameters;however, some of these studies have failed to find a significant correlation between these variables. Herein we have inv... Previous studies have focused on the damaging effects of smoking and alcohol on sperm parameters;however, some of these studies have failed to find a significant correlation between these variables. Herein we have investigated the relationship of infertility with smoking and/or alcohol consumption in one hundred and thirty-six men with varicocele, admitted consecutively to the Outpatients Department of Infertility at the University of Rome La Sapienza (Italy) between 2005-2007. The sample size was small because we have selected couples with both marital infertility lasting for more than two years and the male partner with varicocele. Statistical analyses were carried out using the software of Statistical Package for the Social Sciences (SPSS). We showed a highly significant association of infertility with alcohol consumption. As the mean value was 32 years, comparing men of age less than or equal to 32 years and men of age over 32 years, this association is present only in men of age less than or equal to 32 years. A discriminant analysis with infertility as dependent variable and age, alcohol consumption and smoking habit as independent variables has shown a significant discrimination only in men of age less than or equal to 32 years. The most important contribution to this discrimination was given by alcohol followed by age while contribution from smoking was small. Our analyses suggest that alcohol consumption contributes to infertility in men of age less than or equal to 32 years whereas smoking does not. 展开更多
关键词 age ALCOHOL consumption inFERTILITY SMOKinG VARICOCELE
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High-intensity interval training for health benefits and care of cardiac diseases——The key to an efficient exercise protocol 被引量:11
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作者 Shigenori Ito 《World Journal of Cardiology》 CAS 2019年第7期171-188,共18页
Aerobic capacity, which is expressed as peak oxygen consumption (VO2peak), is well-known to be an independent predictor of all-cause mortality and cardiovascular prognosis. This is true even for people with various co... Aerobic capacity, which is expressed as peak oxygen consumption (VO2peak), is well-known to be an independent predictor of all-cause mortality and cardiovascular prognosis. This is true even for people with various coronary risk factors and cardiovascular diseases. Although exercise training is the best method to improve VO2peak, the guidelines of most academic societies recommend 150 or 75 min of moderate- or vigorous- intensity physical activities, respectively, every week to gain health benefits. For general health and primary and secondary cardiovascular prevention, high-intensity interval training (HIIT) has been recognized as an efficient exercise protocol with short exercise sessions. Given the availability of the numerous HIIT protocols, which can be classified into aerobic HIIT and anaerobic HIIT [usually called sprint interval training (SIT)], professionals in health-related fields, including primary physicians and cardiologists, may find it confusing when trying to select an appropriate protocol for their patients. This review describes the classifications of aerobic HIIT and SIT, and their differences in terms of effects, target subjects, adaptability, working mechanisms, and safety. Understanding the HIIT protocols and adopting the correct type for each subject would lead to better improvements in VO2peak with higher adherence and less risk. 展开更多
关键词 high-intensity interval TRAininG EXERCISE TRAininG Coronary artery disease Chronic heart failure Prevention LIFESTYLE Health Peak O2 consumption AEROBIC capacity
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Forbidden Fruit Tastes the Sweetest—A Study of Norwegians’ Consumption Pattern of Chocolate, Sweets, Salty Snacks, Soft Drinks and the Like
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作者 Annechen Bahr Bugge Randi Lavik 《Food and Nutrition Sciences》 2012年第12期1619-1630,共12页
The theme of this study is eating and drinking patterns for products of which the health authorities want the Norwegian people to reduce their consumption. Although consumption development has shown positive trends ov... The theme of this study is eating and drinking patterns for products of which the health authorities want the Norwegian people to reduce their consumption. Although consumption development has shown positive trends over the past few years, Norwegians still have a much higher intake of such products than what is advisable. The study showed that only a small proportion had not eaten chocolate, sweets, sweet pastries, salty snacks etc. in the last seven days. Young people, men, people with low education and people living in households with children had the highest eating and drinking frequency of these kinds of products. Gender and age had the strongest impact on eating and drinking frequency. However, women had a higher eating rate of chocolate and sweets, and men had a higher eating and drinking frequency of salty snacks and sugary soda. People with low education had a considerably higher frequency of drinking sugary soda than people with high education. Among those who ate these products weekly, there were many who expressed that they would prefer to avoid such products, but that they were often tempted. Among those who ate these products a few times a month or less, few said that they did not like chocolate, sweets, etc. The main reason for having a relatively low eating and drinking frequency was that they perceived such products as unhealthy and fattening. Although there were only a few in the group of respondents who were concerned with healthy eating that had not eaten any of the listed products in the past seven days, this group had a significantly lower frequency of eating chocolate, sweets, etc. than the group that was not concerned with this. It was also clear that people who were health conscious to a greater extent limited eating of such products to the weekends and special occasions than those who were not. In order to succeed in reducing eating and drinking frequency of these products, it will be necessary to draw attention to product availability and social acceptance. 展开更多
关键词 ADVERTISinG age agency Class consumption Food Cultural Codes Gender Health Marketing Nutritional Policy Pseudo Foods Societal Structures
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Analysis and Evaluation of the Chocolate Market in Poland Between 2005-2012 With a Particular Emphasis on Consumers Aged 60 and over
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作者 Joanna Brzostek Barbara Kowrygo 《Economics World》 2014年第2期71-78,共8页
The aim of this paper was to analyze and evaluate the chocolate market in Poland in years 2005-2012 with particular emphasis on older consumer purchasing and consumption behavior. In the study a secondary and primary ... The aim of this paper was to analyze and evaluate the chocolate market in Poland in years 2005-2012 with particular emphasis on older consumer purchasing and consumption behavior. In the study a secondary and primary data were used. Secondary data source was the literature, trade press, Internet publications, and the results of household budget. Primary data were obtained through a survey conducted among the participants of the University of the Third Age. The work turned out to increase the production of chocolate in Poland and increased competition in the sector as a result of changes in ownership. These changes were accompanied by increased consumption of chocolate. It was found that older consumers in their purchasing decisions are guided chiefly by the taste of chocolate, then a habit, brand/manufacturer, and price. Most of them prefer dark chocolate. Nearly half of respondents describe themselves as a reasonable consumer. Having this in mind the traditional assortment of chocolate next to innovative should be on market. 展开更多
关键词 CHOCOLATE major producers consumption of chocolate purchasing and consumption behaviours ofconsumer aged 60 and over
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Age-hardening of surface aged hardening alloy 被引量:1
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作者 李忠厚 刘小萍 +1 位作者 赵金香 徐 重 《中国有色金属学会会刊:英文版》 CSCD 2000年第6期788-790,共3页
Steel T8 treated by plasma surface decarburizing was alloyed by the Xu Tec process with Co,W and Mo. An alloyed layer of Fe Co W Mo with low carbon content was formed on the surface of the high carbon steel, thus an a... Steel T8 treated by plasma surface decarburizing was alloyed by the Xu Tec process with Co,W and Mo. An alloyed layer of Fe Co W Mo with low carbon content was formed on the surface of the high carbon steel, thus an advanced gradient composite was produced. The specimens then were treated by the solution and aging treatments. The characteristics of age hardening of the alloying layer were studied. The hardness of the surface layer increases from HV200 to HV1 200 after the solution treatment at 1 190 ℃ and aging at 400 ℃ for 30 min. The results show that the surface aged high speed steel possesses not only high surface hardness, but also enough bulk strength. [ 展开更多
关键词 high CARBON steel PLASMA decarburizing age HARDENinG SURFACE aged HARDENinG alloy(
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The Maximum Ice Age Glaciation between the Karakorum Main Ridge (K_2) and the Tarim Basin and its Influence on Global Energy Balance 被引量:1
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作者 Matthias Kuhle 《Journal of Mountain Science》 SCIE CSCD 2005年第1期5-22,共18页
A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an an... A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an annual meltwater output. The short Aghil glaciers on the contrary are continental, arid and cold. 2). The present-day oscillations of the Karakorum glaciers are related to their own mass, and are contrary to and independent of the actual climate. Only the short glaciers, with steep tongue fronts, show a present-day positive balance. 3). C- dated Late Glacial moraines indicate14 a 400~800 m thick valley glacier at the former confluence point of the K2-, Sarpo Laggo- and Skamri glaciers. 4). From the evidence of transfluence passes with roches moutonnées, striae and the limits of glacial polishing, as well as moraines and erratics, a High Glacial at least 1200 m thick ice-stream network between the Karakorums and the Kuen Lun north slopes was reconstructed. The Shaksgam and Yarkand valleys were occupied by glaciers coming from west Tibet. The lowest-lying moraines are to be found in the foreland down to 2000 m, indicating a depression of the High Glacial (LGM) snowline (ELA) by 1300 m. 5). The approximately 10,000 measurements of the radiation balance at up to heights of 5500 m on K2 indicate that with incoming energy near the solar constant the reflection from snow- covered ice is up to 70% greater than from rock and rock waste surfaces. 6).These results confirm for the very dry western margins of Tibet an almost complete ice sheet cover in an area with subtropical energy balance, conforming with the Ice Age hypothesis of the author which is based upon the presence of a 2.4 million km2 Tibetan inland ice sheet. This inland ice developed for the first time when Tibet was uplifted over the snowline during the early Pleistocene. As the measured subtropical radiation balance shows, it was able to trigger the Quaternary Ice Ages. 展开更多
关键词 KARAKORUM Tibet ice age glaciation PALEOCLIMATE ice age theory high mountain geomorphology
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Aeolian activity in the southern Gurbantunggut Desert of China during the last 900 years 被引量:1
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作者 LI Wen MU Guijin +2 位作者 YE Changsheng XU Lishuai LI Gen 《Journal of Arid Land》 SCIE CSCD 2023年第6期649-666,共18页
The mineral dust emitted from Central Asia has a significant influence on the global climate system.However,the history and mechanisms of aeolian activity in Central Asia remain unclear,due to the lack of well-dated r... The mineral dust emitted from Central Asia has a significant influence on the global climate system.However,the history and mechanisms of aeolian activity in Central Asia remain unclear,due to the lack of well-dated records of aeolian activity and the intense wind erosion in some of the dust source areas(e.g.,deserts).Here,we present the records of aeolian activity from a sedimentary sequence in the southern Gurbantunggut Desert of China using grain size analysis and optically stimulated luminescence(OSL)dating,based on field sampling in 2019.Specifically,we used eight OSL dates to construct chronological frameworks and applied the end-member(EM)analysis for the grain size data to extract the information of aeolian activity in the southern Gurbantunggut Desert during the last 900 a.The results show that the grain size dataset can be subdivided into three EMs(EM1,EM2,and EM3).The primary modal sizes of these EMs(EM1,EM2,and EM3)are 126.00,178.00,and 283.00μm,respectively.EM1 represents a mixture of the suspension components and saltation dust,while EM2 and EM3 show saltation dust transported over a shorter distance via strengthened near-surface winds,which can be used to trace aeolian activity.Combined with the OSL chronology,our results demonstrate that during the last 900 a,more intensive and frequent aeolian activity occurred during 450-100 a BP(Before Present)(i.e.,the Little Ice Age(LIA)),which was reflected by a higher proportion of the coarse-grained components(EM2+EM3).Aeolian activity decreased during 900-450 a BP(i.e.,the Medieval Warm Period(MWP))and 100 a BP-present(i.e.,the Current Warm Period(CWP)).Intensified aeolian activity was associated with the strengthening of the Siberian High and cooling events at high northern latitudes.We propose that the Siberian High,under the influence of temperature changes at high northern latitudes,controlled the frequency and intensity of aeolian activity in Central Asia.Cooling at high northern latitudes would have significantly enhanced the Siberian High,causing its position to shift southward.Subsequently,the incursion of cold air masses from high northern latitudes resulted in stronger wind regimes and increased dust emissions from the southern Gurbantunggut Desert.It is possible that aeolian activity may be weakened in Central Asia under future global warming scenarios,but the impact of human activities on this region must also be considered. 展开更多
关键词 aeolian activity grain size wind regime Little Ice age Siberian high climatic drying Central Asia
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