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Effects of temperature, particle size, and air humidity on sensibility of typical high-energetic explosives
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作者 WU Sanzhen FANG Mingkun +3 位作者 WU Xingliang GUO Guangfei WANG Junhong XU Sen 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期408-416,共9页
The production and utilization of high-energetic explosives often pose a range of safety hazards,with sensitivity being a key factor in evaluating these risks.To investigate how temperature,particle size,and air humid... The production and utilization of high-energetic explosives often pose a range of safety hazards,with sensitivity being a key factor in evaluating these risks.To investigate how temperature,particle size,and air humidity affect the responsiveness of commonly used high-energetic explosives,a series of BAM(Bundesanstalt für Materialforschung und-prüfung)impact and friction sensitivity tests were carried out to determine the critical impact energy and critical load pressure of four representative high-energetic explosives(RDX,HMX,PETN and CL-20)under different temperatures,particle sizes,and air humidity conditions.The experimental findings facilitated an examination of temperature and particle size affecting the sensitivity of high-energetic explosives,along with an assessment of the influence of air humidity on sensitivity testing.The results clearly indicate that high-energetic explosives display a substantial decline in critical reaction energy when subjected to micrometre-sized particles and an air humidity level of 45%at a temperature of 90℃.Furthermore,it was noted that the critical reaction energy of high-energetic explosives diminishes with an increase in temperature within 25℃−90℃.In the same vein,as the particle sizes of high-energetic explosives increase,so does the critical reaction energy for micrometre-sized particles.High air humidity significantly affects the sensitivity testing of high-energetic explosives,emphasizing the importance of refraining from conducting sensitivity tests in such conditions. 展开更多
关键词 high-energetic explosives temperature particle size air humidity critical reaction energy
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On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-Power Electronics
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作者 Qun Jin Tianxiao Guo +4 位作者 Nicolas Perez Nianjun Yang Xin Jiang Kornelius Nielsch Heiko Reith 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期98-108,共11页
Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity ... Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely challenging.Herein,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane substrate.Its tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are observed.Our proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics. 展开更多
关键词 temperature control Low-power electronics On-chip micro temperature controller Freestanding thermoelectric nano films temperature-sensitive components
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Gypsum-based Silica Gel Humidity-controlling Composite Materials:Preparation,Characterization,and Performance
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作者 李曦 冉茂宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期337-344,共8页
Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based compos... Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based composites were compared with adding different silica gel particle size and proportion.The morphological characteristics,the isothermal equilibrium moisture content curve,moisture absorption and desorption rate,moisture absorption and desorption stability,and humidity-conditioning performance were tested and analyzed.The experimental results show that,compared with pure-gypsum,the surface structure of the gypsum-based composites is relatively loose,the quantity,density and aperture of the pores in the structure increase.The absorption and desorption capacity increase along with the increase of silica gel particle size and silica gel proportion.When 3 mm silica gel particle size is added with a mass ratio of 40%,the maximum equilibrium moisture content of humidity-controlling composites is 0.161 g/g at 98% relative humidity(RH),3.22 times that of pure-gypsum.The moisture absorption and desorption rates are increased,the equilibrium moisture absorption and desorption rates are 2.68 times and 1.61 times that of pure-gypsum at 58.5% RH,respectively.The gypsum-based composites have a good stability,which has better timely response to dynamic humidity changes and can effectively regulate indoor humidity under natural conditions. 展开更多
关键词 humidity controlling composite materials GYPSUM silica gel
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A strength model for cement-stabilized mud subjected to various curing temperatures and its early-stage quality control
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作者 Sijie Liu Rongjun Zhang +1 位作者 Junjie Zheng Lin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4727-4741,共15页
The influence of curing temperature on the strength development of cement-stabilized mud has been well documented in terms of strength-increase rate and ultimate strength.However,the strength development model is not ... The influence of curing temperature on the strength development of cement-stabilized mud has been well documented in terms of strength-increase rate and ultimate strength.However,the strength development model is not mature for the extremely early stages.In addition,there is a lack of studies on quality control methods based on early-stage strength development.This paper presents a strength model for cement-stabilized mud to address these gaps,considering various curing temperatures and early-stage behaviors.In this study,a series of laboratory experiments was conducted on two types of muds treated with Portland blast furnace cement and ordinary Portland cement under four different temperatures.The results indicate that elevated temperatures expedite strength development and lead to higher long-term strength.The proposed model,which combines a three-step conversion process and a hyperbolic model at the reference temperature,enables accurate estimate of the strength development for cement-treated mud with any proportions cured under various temperatures.With this model,a practical early quality control method is introduced for applying cement-stabilized mud in field projects.The back-analysis parameters obtained from a 36-h investigation at temperature of 60C demonstrated a sufficient accuracy in predicting strength levels in practical applications. 展开更多
关键词 Cement-stabilized mud Curing temperature Early stage Quality control Strength development
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Development of Temperature-Humidity Independent Control Air-Conditioning Unit for Residential Buildings 被引量:3
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作者 HAN Xing1,ZHANG Xu1,LIU Jin-tao2,GAO Si-yun2,KANG Yue2(1.Institute of HVAC & Gas,College of Mechanical Engineering,Tongji University,Shanghai 200092,China 2.Hisense R&D Center,Qingdao,266000,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期83-87,共5页
Cooling panels are increasingly used in domestic residential buildings.To provide medium temperature cold water for the cooling panel,and dehumidify the indoor air simultaneously,a new kind of temperature-humidity ind... Cooling panels are increasingly used in domestic residential buildings.To provide medium temperature cold water for the cooling panel,and dehumidify the indoor air simultaneously,a new kind of temperature-humidity independent control air-conditioning unit was developed for single residential house by utilizing multi-variable technology.First,the supply air temperature was studied to determine the proper supply air flow rate for the humidity control.Then,the energy consumption of different temperature-humidity independent control systems was studied.The analysis indicates that unity evaporating temperature can be used to handle the moisture load and sensible heat load in two evaporators.So the unit scheme was put forward.Two evaporators were used to produce medium temperature water and dry air separately,and electric expansion valves were used to control the refrigerant distribution between the two evaporators.Then,experimental work was carried out to investigate the influence of compressor frequency,refrigerant distribution on the dehumidification capacity,energy efficiency and refrigeration capacity.In the end,the paper concludes that both compressor frequency and refrigerant distribution can control the dehumidification capacity,but the former influences the EER more than the latter,while the latter influences the refrigeration capacity more than the former.We can find a proper running point at certain sensible and latent cooling load by adjusting both compressor frequency and electric expansion valve.The energy consumption of this kind of unit was estimated and compared with present room air conditioners,which shows that it can save about 41% cooling energy consumption. 展开更多
关键词 temperature-humidity INDEPENDENT control RESIDENTIAL BUILDINGS COLD DEhumidIFICATION experimental study
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COMPUTER DECOUPLE CONTROL OF TEMPERATURE AND HUMIDITY IN PREPROCESSING CHAMBER OF AIR-CONDITIONING TEST EQUIPMENT
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作者 陆宏正 盖其祥 《Journal of China Textile University(English Edition)》 EI CAS 1989年第2期29-34,共6页
This paper deals with the application of decouple Control theory to temperature and humidi-ty control in air-conditioning system. The decouple control algorithm for bivariable systems isderived applicablly for air-con... This paper deals with the application of decouple Control theory to temperature and humidi-ty control in air-conditioning system. The decouple control algorithm for bivariable systems isderived applicablly for air-conditioning system. The algorithm is used to design a temperatureand humidity computer control system for the preprocessing chamber of air-conditioning testequipment. The results of the real-time control experiments indicate that the decouple controlalgorithm is feasible, the control quality is improved and high control precision is achieved. 展开更多
关键词 COMPUTER applications COMPUTER control DECOUPLING temperature control SYSTEM humidity control SYSTEM air conditioning control
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Effects of Land Cover on Soil Temperature,Humidity and Moisture in Phoebe bournei Forest 被引量:9
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作者 吴际友 陈明皋 +5 位作者 董春英 黄小飞 黄明军 程勇 刘球 吴其军 《Agricultural Science & Technology》 CAS 2015年第12期2725-2729,共5页
Under the condition of high temperature, the effects of five cover patterns (clean tillage, film mulching, weed covering, branches and leaves covering and growing grass covering) on soil properties in young Phoebe b... Under the condition of high temperature, the effects of five cover patterns (clean tillage, film mulching, weed covering, branches and leaves covering and growing grass covering) on soil properties in young Phoebe boumei forest were in- vestigated. The results showed that the five cover patterns all showed significant ef- fects on soil properties in young Phoebe bournei forest under the condition of high temperature. Land cover increased land temperature in Phoebe boumei forest. Un- der the film mulching, the land temperature was increased most rapidly with the largest increment. However, weed covering, branches and leaves covering and growing grass covering decreased land temperature. Among them, growing grass covering showed the best cooling effect. The film mulching, weed covering, branch- es and leaves covering and growing grass covering all increased land humidity. The film mulching showed the best moisture-preserving effect in the early period, but in the late period, the humidity in the film mulching treatment group was lower than that in the clean tillage treatment group. Among the five mulching patterns, moisture loss in the film mulching treatment group was slowest and least, followed by those in the weed covering and branches and leaves covering treatment groups, and moisture loss in the growing grass covering treatment group was fastest and most. 展开更多
关键词 Soil management Land cover Land temperature Land humidity Soil moisture
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Temperature and Humidity Control in Greenhouses in Desert Areas
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作者 Shigeki Hirasawa Mai Nakatsuka +2 位作者 Kunio Masui Tsuyoshi Kawanami Katsuaki Shirai 《Agricultural Sciences》 2014年第13期1261-1268,共8页
Water consumption can be reduced by using a greenhouse for agriculture in desert areas. We analyzed the effect of control of ventilation, sprinkler water, and solar radiation?shielding on changes of temperature and hu... Water consumption can be reduced by using a greenhouse for agriculture in desert areas. We analyzed the effect of control of ventilation, sprinkler water, and solar radiation?shielding on changes of temperature and humidity in a greenhouse under various desert area conditions. We calculated the changes in temperature and humidity in a greenhouse for a whole day in four seasons, and the calculation results of water consumption with and without a greenhouse were compared. When ventilation, shielding, and sprinkler water were controlled under suitable conditions to grow orchids in a desert area, water consumption in July was only 7% of that without a greenhouse. 展开更多
关键词 temperature control humidity Ventilation SPRINKLER Water HEAT TRANSFER GREENHOUSE DESERT
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Design of greenhouse temperature and humidity wireless control system based on CC3200
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作者 ZHAO Cheng-cheng DING Hai-fei +1 位作者 LIU Wen-yi KANG Xi 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第2期134-139,共6页
Referring to the shortages that the process of traditional greenhouse measurement by using thermometer and hygrometer is complex,the measurement result is not accurate,and the control system operation is cumbersome,a ... Referring to the shortages that the process of traditional greenhouse measurement by using thermometer and hygrometer is complex,the measurement result is not accurate,and the control system operation is cumbersome,a greenhouse temperature and humidity(TH)control system based on CC3200 is designed.The system uses FPGA as the main controller,sends the TH signals to the wireless module CC3200 by controlling DHT22.The proposed system realizes the remote transmission of data and the automatic control of system. 展开更多
关键词 field programmable gate array(FPGA) CC3200 DHT22 temperature and humidity(TH)of greenhouse wireless control
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Impact of Variegated Temperature, CO<SUB>2</SUB>and Relative Humidity on Survival and Development of Beet Armyworm <i>Spodoptera exigua</i>(Hubner) under Controlled Growth Chamber
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作者 Jagdish Jaba Suraj Prashad Mishra +1 位作者 Naveen Arora Rajendra Munghate 《American Journal of Climate Change》 2020年第4期357-370,共14页
Climate change will have a noteworthy bearing on survival, development, and population dynamics of insect pests. Therefore, we contemplated the survival and development of beet army worm, <em>Spodoptera exigua&l... Climate change will have a noteworthy bearing on survival, development, and population dynamics of insect pests. Therefore, we contemplated the survival and development of beet army worm, <em>Spodoptera exigua</em> under different temperatures, (15<span style="white-space:nowrap;">&#176;</span>C, 25<span style="white-space:nowrap;">&#176;</span>C, 35<span style="white-space:nowrap;">&#176;</span>C, and 45<span style="white-space:nowrap;">&#176;</span>C), CO<sub>2</sub> (350, 550, 750 ppm) and relative humidity (55%, 65%, 75% and 85%) regimes. Maximum larval and pupal weights were recorded in insects reared at 25<span style="white-space:nowrap;">&#176;</span>C. The growth of <em>S. exigua</em> was faster at 35<span style="white-space:nowrap;">&#176;</span>C (larval period 7.4 days and pupal period 4.5 days) than at lower temperatures. At 15<span style="white-space:nowrap;">&#176;</span>C, the larval period was extended for 61.4 days and there was no adult emergence from the pupae till 90 days. The <em>S. exigua</em> hatchling was absent at 45<span style="white-space:nowrap;">&#176;</span>C. The larval survival ranged from 31.6% - 57.2%, maximum survival was recorded at 25<span style="white-space:nowrap;">&#176;</span>C, and minimum at 45<span style="white-space:nowrap;">&#176;</span>C. The maximum (84.27%) and minimum adult emergence were recorded in insects reared at 25<span style="white-space:nowrap;">&#176;</span>C and 35<span style="white-space:nowrap;">&#176;</span>C respectively. Maximum fecundity (384.3 eggs/female) and egg viability (51.97%) were recorded in insects reared at 25<span style="white-space:nowrap;">&#176;</span>C. Larval and pupal periods increased with an increase in CO<sub>2</sub> concentration. The highest pupal weights (128.6 mg/larva) were recorded at 550 ppm. The highest larval survival (73.50%) was recorded at 550 ppm and minimum (37.00%) at 750 ppm CO<sub>2</sub>. Fecundity was the highest in insects reared at 550 ppm CO<sub>2</sub> (657.4 eggs/female), and the lowest at 750 ppm. Maximum larval and pupal weights were recorded in insects reared at 75% relative humidity (RH). The growth rate of<em> S. exigua</em> was faster at 85% RH than at lower RH. The larval survival ranged between 40.0% - 58.5%. Maximum adult emergence (88.91%) was recorded in insects reared at 75% RH and minimum at 85% RH. Maximum fecundity (447.6 eggs/female) and the highest egg viability (72.95%) were recorded in insects reared at 75% and 65% RH respectively. Elevated temperatures and relative moistness will diminish the life cycle, while hoisted CO<sub>2</sub> will drag the life expectancy. Therefore, there is a need for thorough assessment of the impact of climatic factors on the population dynamics of insect pests, crop losses, and sustainability of crop production. 展开更多
关键词 Spodoptera exigua temperature CO2 Relative humidity and Climate Change
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Study on Temperature and Humidity of Plastic Greenhouse under Different Ventilation Modes in the Yangtze-Huai Region in Hot Season 被引量:1
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作者 孟力力 刘建龙 +3 位作者 柳军 夏礼如 唐玉邦 虞利俊 《Agricultural Science & Technology》 CAS 2016年第12期2885-2888,2900,共5页
In order to analyze the ventilation and cooling performance of single-tunnel plastic greenhouse in Yangtze-Huai region, the effects of two different ventilation modes (side window, side window+roof window) on the t... In order to analyze the ventilation and cooling performance of single-tunnel plastic greenhouse in Yangtze-Huai region, the effects of two different ventilation modes (side window, side window+roof window) on the temperature and humidity of plastic greenhouse were studied. The results showed that the ventilation mode of opening side window and roof window could effectively reduce the temperature and humidity at the plant canopy height, which was conducive to the growth of plant in greenhouse. 展开更多
关键词 Plastic greenhouse temperature humidity Ventilation COOLING
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Design of Expert PID Control System on Temperature and Humidity Verifying Box 被引量:1
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作者 TIAN Ke-lun 《科技视界》 2012年第24期80-82,共3页
This paper briefly introduces the characteristics of structure and optimum design of the hardware of the expert PID control system on temperature and humidity verifying box.Combined Microcontroller technology with exp... This paper briefly introduces the characteristics of structure and optimum design of the hardware of the expert PID control system on temperature and humidity verifying box.Combined Microcontroller technology with expert PID control technology and with regular construction of temperature-humidity expert control system,the paper sets up the expert control rules,as well as a subset of control flow. 展开更多
关键词 英语教学 教学方法 阅读教学 英语翻译
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Temperature and Humidity Control System Identification Based on Neural Network in Heating and Drying System
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作者 Zhang Xiaowei 《International Journal of Technology Management》 2014年第7期81-85,共5页
Artificial neural network has unique advantages for massively parallel processing, distributed storage capacity and self-learning ability. The paper mainly constructs neural network identifier and neural network contr... Artificial neural network has unique advantages for massively parallel processing, distributed storage capacity and self-learning ability. The paper mainly constructs neural network identifier and neural network controller for system identification and control on temperature and hmnidity of heating and drying system of materials. And the paper introduces the structure and principles of neural network, and focuses on analyzing learning algorithm, training algorithm and limitation of the most widely applied multi-layer feed-forward neural network ( BP network) , based on which the paper proposes introducing momentum to improve BP network. 展开更多
关键词 neural network BP algorithm material heating and drying temperature humidity
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Temperature-Based Fan Speed Optimization Strategy
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作者 Chucheng Wang Chongyi Luo +3 位作者 Junnian Wei Haiyang Peng Xiaorong Zhong Cai Ye 《Journal of Electronic Research and Application》 2024年第3期135-141,共7页
As energy efficiency and indoor comfort increasingly become key standards in modern residential and office environments,research on intelligent fan speed control systems has become particularly important.This study ai... As energy efficiency and indoor comfort increasingly become key standards in modern residential and office environments,research on intelligent fan speed control systems has become particularly important.This study aims to develop a temperature-feedback-based fan speed optimization strategy to achieve higher energy efficiency and user comfort.Firstly,by analyzing existing fan speed control technologies,their main limitations are identified,such as the inability to achieve smooth speed transitions.To address this issue,a BP-PID speed control algorithm is designed,which dynamically adjusts fan speed based on indoor temperature changes.Experimental validation demonstrates that the designed system can achieve smooth speed transitions compared to traditional fan systems while maintaining stable indoor temperatures.Furthermore,the real-time responsiveness of the system is crucial for enhancing user comfort.Our research not only demonstrates the feasibility of temperature-based fan speed optimization strategies in both theory and practice but also provides valuable insights for energy management in future smart home environments.Ultimately,this research outcome will facilitate the development of smart home systems and have a positive impact on environmental sustainability. 展开更多
关键词 Smart temperature control Fan speed optimization temperature feedback control Dynamic speed adjustment Smart home systems Energy-saving technology
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Reinforced temperature control of a reactive double dividing-wall distillation column
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作者 Wei Qin Lijing Zang +5 位作者 Kejin Huang Haisheng Chen Yang Yuan Xing Qian Liang Zhang Shaofeng Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期288-295,共8页
The mass and thermal coupling makes the control of the reactive double dividing-wall distillation column(R-DDWDC) an especially challenging issue with a highly interactive nature. With reference to the separation of a... The mass and thermal coupling makes the control of the reactive double dividing-wall distillation column(R-DDWDC) an especially challenging issue with a highly interactive nature. With reference to the separation of an ideal endothermic quaternary reversible reaction with the most unfavorable ranking of relative volatilities(A + B ■ C + D with α_(A)>α_(C)>α_(D)>α_(B)), the operation rationality of the R-DDWDC is studied in this contribution. The four-point single temperature control system leads to great steady-state discrepancies in the compositions of products C and D and the reason stems essentially from the failure in keeping strictly the stoichiometric ratio between reactants A and B. A temperature plus temperature cascade control scheme is then employed to reinforce the stoichiometric ratio control and helps to secure a substantial abatement in the steady-state discrepancies. A temperature difference plus temperature cascade control scheme is finally synthesized and leads even to better performance than the most effective double temperature difference control scheme. These outcomes reveal not only the operation feasibility of the R-DDWDC but also the general significance of the proposed temperature difference plus temperature cascade control scheme to the inferential control of any other complicated distillation columns. 展开更多
关键词 Reactive double dividing-wall distillation column temperature control temperature plus temperature cascade control temperature difference plus temperature cascade control Process operation
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Experimental study on temperature stress calculation and temperature control optimization of concrete based on early age parameters
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作者 HU Yintao ZHOU Qiujing +3 位作者 YANG Ning QIAO Yu JIA Fan Xin Jianda 《中国水利水电科学研究院学报(中英文)》 北大核心 2023年第6期586-597,共12页
Temperature control curve is the key to achieving temperature control and crack prevention of high concrete dam during construction,and its rationality depends on the accurate measurement of temperature stress.With th... Temperature control curve is the key to achieving temperature control and crack prevention of high concrete dam during construction,and its rationality depends on the accurate measurement of temperature stress.With the simulation testing machine for the temperature stress,in the present study,we carried out the deformation process tests of concrete under three temperature curves:convex,straight and concave.Besides,we not only measured the early-age elastic modulus,creep parameters and stress process,but also proposed the preferred type.The results show that at early age,higher temperature always leads to greater elastic modulus and smaller creep.However,the traditional indoor experiments have underestimated the elastic modulus and creep development at early age,which makes the calculated value of temperature stress too small,thus increasing the cracking risk.In this study,the stress values of the three curves calculated based on the strain and early-age parameters are in good agreement with the temperature stress measured by the temperature stress testing machine,which verifies the method accuracy.When the temperature changes along the concave curve,the law of stress development is in consistent with that of strength.Under this condition,the stress fluctuation is small and the crack prevention safety of the concave type is higher,so the concave type is better.The test results provide a reliable basis and support for temperature control curve design and optimization of concrete dams. 展开更多
关键词 concrete dam temperature control curve early-age parameters temperature stress testing machine elastic modulus
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Optimization of the Plugging Agent Dosage for High Temperature Salt Profile Control in Heavy Oil Reservoirs
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作者 Jiayu Ruan Mingjing Lu +5 位作者 Wei Zhang Yuxi Zhang Yuhui Zhou Jie Gong Fan Wang Yuanxiao Guan 《Fluid Dynamics & Materials Processing》 EI 2023年第2期421-436,共16页
After steam discharge in heavy oil reservoirs,the distribution of temperature,pressure,and permeability in different wells becomes irregular.Flow channels can easily be produced,which affect the sweep efficiency of th... After steam discharge in heavy oil reservoirs,the distribution of temperature,pressure,and permeability in different wells becomes irregular.Flow channels can easily be produced,which affect the sweep efficiency of the oil displacement.Previous studies have shown that the salting-out plugging method can effectively block these channels in high-temperature reservoirs,improve the suction profile,and increase oil production.In the present study,the optimal dosage of the plugging agent is determined taking into account connection transmissibility and inter-well volumes.Together with the connectivity model,a water flooding simulation model is introduced.Moreover,a non-gradient stochastic disturbance algorithm is used to obtain the optimal plugging agent dosage,which provides the basis for the high-temperature salting-out plugging agent adjustment in the field. 展开更多
关键词 Heavy oil salting out profile control high temperature plugging agent dosage optimization numerical simulation connectivity model
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Effects of Extreme Air Temperature and Humidity on the Insecticidal Expression Level of Bt Cotton 被引量:12
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作者 CHENYuan WEN Yu-jin +5 位作者 CHEN Yuan John Tom Cothren ZHANG Xiang WANG Yong-hui WilliamA Payne CHEN De-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第11期1836-1844,共9页
The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature (T) and relative humidity (RH) stresses in transgenic Bacillus thuringie... The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature (T) and relative humidity (RH) stresses in transgenic Bacillus thuringiensis (Bt) cotton. The unstable resistance of Bt cotton to bollworms has been correlated with the reduced expression of CrylAc δ-endotoxin. The objective of this study was to investigate the effects of combined temperature and relative humidity stresses on the leaf CrylAc insecticidal protein expression during critical developmental stages. The study was undertaken on two transgenic cotton cultivars that share same parental background, Sikang 1 (a conventional cultivar) and Sikang 3 (a hybrid cultivar), during the 2007 and 2008 growing seasons at the Yangzhou University Farm, Yangzhou, China. The study was arranged with two factors that consisted of temperature (two levels) and relative humidity (three levels). The six T/RH treatments were 37℃/95%, 37℃/70%, 37℃/50%, 18℃/95%, 18℃/70%, and 18℃/50%. In 2007, the six treatments were imposed to the plants at peak flowering stage for 24 h; in 2008, the six treatments were applied to the plants at peak square, peak flowering, and peak boll stages for 48 h. The results of the study indicated that the leaf insecticidal protein expression in CrylAc was significantly affected by extreme temperature only at peak flowering stage, and by both extreme temperature and relative humidity during boll filling stage. The greatest reductions were observed when the stresses were applied at peak boll stage. In 2008, after 48 h stress treatment, the leaf Bt endotoxin expression reduced by 25.9-36.7 and 23.6-40.5% at peak boll stage, but only by 14.9-26.5 and 12.8-24.0% at peak flowering stage for Sikang 1 and Sikang 3, respectively. The greatest reduction was found under the low temperature combined with low relative humidity condition for both years. It is believed that the temperature and relative humidity stresses may be attributed to the reduced efficacy of Bt cotton in growing conditions in China, where extreme temperatures often increase up to 35-40℃ and/or decrease down to 15-20℃, and relative humidity may reach to 85-95% and/or reduce to 40-55% during the cotton growing season. 展开更多
关键词 Bt cotton high temperature low temperature relative humidity CryIAc protein
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Spatial distribution of air temperature and relative humidity in the greenhouse as affected by external shading in arid climates 被引量:9
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作者 Hesham AAhmed TONG Yu-xin +2 位作者 YANG Qi-chang Abdulellah AAl-Faraj Ahmed MAbdel-Ghany 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第12期2869-2882,共14页
The effect of external roof shading on the spatial distribution of air temperature and relative humidity in a greenhouse(Tin and RHin) was evaluated under the arid climatic conditions of Riyadh City, Saudi Arabia. Two... The effect of external roof shading on the spatial distribution of air temperature and relative humidity in a greenhouse(Tin and RHin) was evaluated under the arid climatic conditions of Riyadh City, Saudi Arabia. Two identical, evaporatively-cooled, single-span greenhouses were used in the experiment. One greenhouse was externally shaded(Gs) using a movable black plastic net(30% transmissivity), and the other greenhouse was kept without shading(Gc). Strawberry plants were cultivated in both greenhouses. The results showed that the spatial distribution of the Tin and RHin was significantly affected by the outside solar radiation and evaporative cooling operation. The regression analysis showed that when the outside solar radiation intensity increased from 200 to 800 W m–2, the Tin increased by 4.5℃ in the Gc and 2℃in the Gs, while the RHin decreased by 15% in the Gc and 5% in the Gs, respectively. Compared with those in the Gc, more uniformity in the spatial distribution of the Tin and RHin was observed in the Gs. The difference between the maximum and minimum Tin of 6.4℃ and the RHin of 10% was lower in the Gs than those in the Gc during the early morning. Around 2℃ difference in the Tin was shown between the area closed to the exhausted fans and the area closed to the cooling pad with the external shading. In an evaporatively-cooled greenhouse in arid regions, the variation of the Tin and RHin in the vertical direction and along the sidewalls was much higher than that in the horizontal direction. The average variation of the Tin and RHin in the vertical direction was 5.2℃ and 10% in the Gc and 5.5℃ and 13% in the Gs, respectively. The external shading improved the spatial distribution of the Tin and RHin and improved the cooling efficiency of the evaporative cooling system by 12%, since the transmitted solar radiation and accumulated thermal energy in the greenhouse were significantly reduced. 展开更多
关键词 GREENHOUSE temperature humidity distribution UNIFORMITY EVAPORATIVE cooling SHADING ARID climate
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Visco-elastic-plastic model of deep underground rock affected by temperature and humidity 被引量:9
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作者 GAO, Yanan GAO, Feng +1 位作者 ZHANG, Zhizhen ZHANG, Tao 《Mining Science and Technology》 EI CAS 2010年第2期183-187,共5页
As the depth of exploitation increases,studies on constitutive models of rock affected by temperature and humidity become very important.Based on the Nishihara model,a visco-elastic-plastic rock model was established ... As the depth of exploitation increases,studies on constitutive models of rock affected by temperature and humidity become very important.Based on the Nishihara model,a visco-elastic-plastic rock model was established by using the coefficients of thermal and humidity expansion,thermal viscosity attenuation,humid viscosity attenuation and acceleration rheology components.We used the definition of a controlled heat circle to explain the model.The results show that the behavior of rock,affected by temperature and humidity,is stable as a function of time when the stress is lower than the first yield stress σS1;the creep rate will increase due to the effect of temperature and humidity when the stress is greater than or equal to σS1;the creep rate will accelerate at an increasing rate when the stress is greater than or equal to the second yield stress σS2,which results in a failure of the roadway.The model derived in this study can completely describe visco-elastic-plastic characteristics and reflects the three stages of rock creep. 展开更多
关键词 temperature humidity CREEP controlled heat circle
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