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Effect of Carbon Dioxide (CO_2) Controlled Atmosphere on Superoxide Dismutase (SOD) Activity of Three Storage Pests in Chinese Medicinal Materials 被引量:2
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作者 李灿 《Plant Diseases and Pests》 CAS 2011年第4期43-45,共3页
[ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide ( CO2 ) on Superoxide dismutase (SOD) activity of in- sect, so as to analyze the biological mechanism of the action... [ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide ( CO2 ) on Superoxide dismutase (SOD) activity of in- sect, so as to analyze the biological mechanism of the action of controlled atmosphere stress on insect. [ Method] Using nitrotetrazolium blue chloride (NBT) light reduction method, SOD activity of drugstore beetle ( Stegobium panlceum ), cigarette beetle ( Lasioderma serricorne) and coffee bean beetle (Araecerus fasciculatus) was studied, and the stress response of the enzyme under controlled atmosphere stress of CO2 was analyzed. [ Result ] SOD activity of drugstore beetle, cigarette beetle and coffee bean beetle exposed to controlled atmosphere stress of high concentrations of CO2 for 3 and 6 h had certain degree of increase, and the activity sig- nificantly increased from 2.011±0.954,2.664±0.218 and 1.458±0.718 to 3. 135±0. 105,3.050±0.673 and 2.975±0.229 U/(per pest · 30 min) after treat- ment for 6 h. [ Conclusion] Controlled atmosphere stress of high concentrations of CO2 had certain activation effect on SOD activity of storage pest in Chinese me- dicinal material within the context of sub-lethal events. The results could enrich the insecticidal mechanism of controlled atmosphere and theoretical system of analy- sis on insect resistance to controlled atmosphere. 展开更多
关键词 Chinese medicinal materials Storage pest Superoxide dismulase Enzyme activity CO2 controlled atmosphere China
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Effect of Controlled Atmosphere Storage(CAS)Technology of Flue-cured Tobacco Laminas on the Alcoholization Quality of Tobacco
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作者 杨欣玲 《Agricultural Science & Technology》 CAS 2017年第12期2547-2553,共7页
To achieve the continuous maintainence of optimum quality state of flue- cured tobacco laminas and the effective regulation and control on alcoholization time for controlled atmosphere storage (CAS) method in the pr... To achieve the continuous maintainence of optimum quality state of flue- cured tobacco laminas and the effective regulation and control on alcoholization time for controlled atmosphere storage (CAS) method in the process of storage, the lam- ina samples of natural alcoholization for 1 year were selected. Comparable analysis on the appearance quality, chemical components and sensory quality of flue-cured tobacco laminas in the process of alcoholization was carried out by using the meth- ods of CAS and natural alcoholization. The results showed that appearance and color through the treatment of natural alcoholization were deep, browning and ac- companied by the phenomenon of oil, while color scale of flue-cured tobacco lami- nas through the treatment of CAS was uniform, fullness was better, and these two methods were close or identical after opening for 3 months. The contents of total sugar and reducing sugar during the process of alcoholization were also gradually decreased, but the ratio of reducing sugar to total sugar of laminas via CAS was higher than that of the natural alcoholization treatment. Compared with the natural alcoholization,the descending trends of total nitrogen and nicotine contents during CAS were gentler, the ratio via CAS was closer to 1, and the coordination of chemical components was more superior. During the period of alcoholization for 6 to 12 months, sensory quality of laminas via the natural alcoholization treatment was more superior than that of CAS treatment. However, after 18 months of alcoholiza- tion, sensory quality of laminas via the CAS treatment was more superior than that of the natural alcoholization treatment, and the CAS treatment could improve opti- mum sensory quality by 0.5 to 1.5 scores. Additionally, the CAS treatment could prolong the time of optimum alcoholization quality for 6 months, compared with the treatment of natural alcoholization. The CAS method could influence the alcohoJiza- tion quality of flue-cured tobacco laminas and prolong the retention period of opti- mum quality status for flue-cured tobacco laminas by regulating the environmental aas composition, thereby realizin.q quality control of flue-cured tobacco laminas. 展开更多
关键词 Flue-cured tobacco laminas controlled atmosphere storage caS) To-bacco alcoholization Chemical components Sensory quality Alcoholization peak
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High temperature oxidation of inoculated high Si/SiMo ductile cast irons in air and combustion atmospheres
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作者 Iuliana Stan Mihai Chisamera +5 位作者 Robert Lascu Codrut Cariga Eduard Stefan Stelian Stan Denisa Anca Iulian Riposan 《China Foundry》 SCIE EI CAS CSCD 2024年第5期555-562,共8页
The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry ... The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry air and combustion gas containing water vapour(natural gas burning).The oxidation is influenced by the gas atmosphere type,the iron alloying system,and the inoculating elements depending on the heating temperature.The weight gain increases from 0.001%-0.1%(400°C)to 0.05%-0.70%(600°C)and up to 0.10%-2.15%(800°C).No particular effects of the considered influencing factors are found when heating at 400°C,while at 600°C,mainly the oxidation gas atmosphere type shows a visible influence.At the highest heating temperature of 800°C,a limited increase of the weight gain is found for dry air atmosphere(up to 0.25%),but it drastically increases for combustion atmospheres(0.65%-2.15%).The water vapour presence in the combustion atmosphere is an important oxidising factor at 600-800°C.The alloying system appears to influence the oxidation behavior mainly at a heating temperature of 800°C in the combustion atmosphere,as evidenced by the lower weight gain in 5.25%silicon cast iron.Positive effects of inoculating elements increase with the heating temperature,with Ca and Ba-FeSi inoculation generally showing better performance.Irons inoculated with CaRE-FeSi exhibit a higher degree of oxidation.These results are in good relationship with the previous reported data:Ca-Ba-inoculation system appears to be better than simple Ca for improving the graphite parameters,while RE-bearing inoculant negatively affects the compactness degree of graphite particles in high-Si ductile irons.As the lower compactness degree is typical for graphite nodules in high-Si ductile irons,which negatively affects the oxidation resistance,it is necessary to employ specific metallurgical treatments to improve nodule quality.Inoculation,in particular,is a potential method to achieve this improvement. 展开更多
关键词 ductile iron spheroidal graphite Si/SiMo oxidation air/combustion atmospheres FeSicaMgRE treatment ca ca-Ba ca-RE inoculation structure characteristics
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Changes in Enzymatic Activity and Quality Attributes of Late-mature Peaches in Response to Controlled Atmosphere Conditions 被引量:7
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作者 TIAN Shi-ping, XU Yong, JIANG Ai-li and WANG Yi( Institute of Botany , Chinese Academy of Sciences , Beijing 100093 ) 《Agricultural Sciences in China》 CAS CSCD 2002年第2期207-212,共6页
Late-mature peaches (Prunus persica L. Batsch, cv. Dongxuemi) were stored in air, modification atmosphere (MA) and controlled atmospheres (CA) at 1℃ to investigate enzymatic activities, flesh browning, quality attrib... Late-mature peaches (Prunus persica L. Batsch, cv. Dongxuemi) were stored in air, modification atmosphere (MA) and controlled atmospheres (CA) at 1℃ to investigate enzymatic activities, flesh browning, quality attributes and fruit storability during storage periods. Peaches stored in CA conditions showed significant lower activities of polyphenol oxidase (PPO) and peroxidase (POD) compared to that kept in MA and in air during the early period of storage. CA treatments indicated a better result in maintaining fruit firmness, color and titratable acidity than MA and control treatments. But there was no significant difference in vitamin C and total soluble solids of peaches stored in CA, MA and air. Increasing PPO activity obviously stimulated flesh browning. Peach fruits stored in CA conditions showed a lower activity of POD and higher firmness in the early period of storage. The peaches stored in 5%CO2 + 5%O2 and 10%CO2 + 5%O2 for 92 days had a good quality without any off-flavor. The results indicated CA conditions obviously inhibited the enzymatic browning, delayed senescence and maintained quality of late-mature peaches. 展开更多
关键词 PEACHES controlled atmospheres PPO POD Quality attributes
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OXIDATION BEHAVIOR OF KOVAR ALLOY IN CONTROLLED ATMOSPHERE 被引量:11
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作者 D. W. Luo Z.S. Shen 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第6期409-418,共10页
Controlled oxidation experiments were performed on Kovar alloy by changing oxidation atmosphere, temperature, and exposure time to produce films with different oxide type and thickness. The results indicated that sing... Controlled oxidation experiments were performed on Kovar alloy by changing oxidation atmosphere, temperature, and exposure time to produce films with different oxide type and thickness. The results indicated that single Fe3O4 and single FeO were respectively obtained when Kovar alloy was oxidized in N2-2.31%H2O-0.95%H2 at 500℃ and in N2-2.31%H2O-0.5%H2 at 1000℃, and all kinetic curves followed linear relation; mixed oxides of FeO and Fe3O4 formed when Kovar was oxidized in N2-2.31%H2O at 1000℃and parabolic kinetics were obeyed. Analysis of metallographic cross section of oxides indicated that oxygen diffusion inward through the oxide scale is responsible for intergranular oxide, which had formed beneath the oxide scales when the oxide products were mixed oxides of FeO and Fe3O4, and which did not occur when the oxide was single FeO or Fe3O4. The oxidation model was also established. 展开更多
关键词 Kovar alloy Oxidation controlled atmosphere H2-H2O-N2
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The Relationship Between Resistance to Controlled Atmosphere and Insecticides of Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae) 被引量:1
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作者 DINGWei ZHAOZhi-mo WANGJin-jun TAOHui-ying ZHANGYong-qiang 《Agricultural Sciences in China》 CAS CSCD 2004年第11期822-830,共9页
The cross resistance of four resistant strains of Liposcelis bostrychophila Badonnel, an important stored-product insect pest, was investigated. These four strains included the HCO2-R (hypercarbia-resistant strain),... The cross resistance of four resistant strains of Liposcelis bostrychophila Badonnel, an important stored-product insect pest, was investigated. These four strains included the HCO2-R (hypercarbia-resistant strain), HCLO-R (hypoxia and hypercarbia resistant strain), DDVP-R (DDVP-resistant strain) and PH3-R (PH3-resistant strain). The results indicated that there were cross-resistances between CA and insecticides, and the quantities of the cross-resistance were different. The cross-resistance factor (RF) of HCO2-R to hypoxia and hypercarbia was 3.2458, whilst, that of HCLO-R to hypercarbia was 1.8280. The RF of DDVP-R to PH3 was 3.9614, whilst, that of PH3-R to DDVP was 2.7852. The RF values of DDVP- R and PH3-R to hypercarbia were 1.3550 and 1.1816, respectively. However, the RF of HCO2- R to DDVP was 2.1372. There also was a low cross-resistance between DDVP-R and HCO2-R. The RF of HCO2-R to PH3 was 3.3698. This suggested that the insects resistant to high CO2 concentration atmosphere would develop significant resistance to PH3. However, the insects resistant to PH3 remain sensitive to hypercarbia atmosphere. Both DDVP-R and PH3- R developed resistance to high CO2 treatment. There was a low cross-resistance between DDVP-R and HCLO-R. The insects resistant to hypoxia and hypercarbia were very sensitive to DDVP. There also was cross-resistance between HCLO-R and PH3-R, but the resistance of PH3-R to hypoxia and hypercarbia was lower than that of HCLO-R to PH3. The difference of the overlapping and separate values indicated that there were differences in the intercross-resistance of four resistant strains. 展开更多
关键词 Liposcelis bostrychophila Badonnel CROSS-RESISTANCE Resistance to controlled atmosphere (ca) Resistance to insecticides Double direction cross-resistance
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Storability of “Jonagold” Apple Fruit under Extreme Controlled Atmosphere Conditions 被引量:1
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作者 Adriano Arriel Saquet 《Journal of Agricultural Science and Technology(B)》 2016年第4期262-268,共7页
In two consecutive seasons, the storage capacity of “Jonagold” apple fruit was investigated under regular air (RA) and various controlled atmosphere (CA) conditions during six months at 0 ± 0.3 °C. The dif... In two consecutive seasons, the storage capacity of “Jonagold” apple fruit was investigated under regular air (RA) and various controlled atmosphere (CA) conditions during six months at 0 ± 0.3 °C. The different CA treatment combinations were: (1) 0.5 kPa O2 + 0.5 kPa CO2, (2) 2.0 kPa O2 + 1.0 kPa CO2, (3) 1.0 kPa O2 + 3.0 kPa CO2 and (4) 0.5 kPa O2 + 6.0 kPa CO2. Ethylene production and respiration rate were evaluated at each two months storage intervals during 7 d shelf life at 20 °C. Fruit quality traits were analyzed immediately at the end of storage period and after 7 d shelf life at 20 °C. Under CA treatment, the lower the O2 and/or the higher the CO2 partial pressure, the stronger was the inhibition of the ethylene production and respiration rate of apple fruit. The 0.5 kPa O2 + 6.0 kPa CO2 CA condition induced the strongest suppression in ethylene production and consequently lower CO2 release by apple fruit. At the end of storage period, “Jonagold” apple fruit was very tolerant to all CA conditions, and any kind of internal storage disorders was observed. The storage of “Jonagold” apple at 1.0 kPa O2 + 3.0 kPa CO2 and 0.5 kPa O2 + 6.0 kPa CO2 proportionated higher flesh firmness (FF), greener skin color (SC) and higher titratable acidity (TA) either immediately after storage or after 7 d shelf life at 20 °C. Total soluble solids were not significantly affected by CA storage conditions. 展开更多
关键词 carbon dioxide “Jonagold” APPLE controlled atmosphere CONDITIONS FRUIT quality ultra-low oxygen
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Development and Performance Study of Controlled Atmosphere for Fresh Tomato
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作者 Md. Farid Ahmed Md. Zahirul Islam +2 位作者 Md. Sazzat Hossain Sarker S. M. Kamrul Hasan Rakib Mizan 《World Journal of Engineering and Technology》 2016年第2期168-175,共8页
Development of a controlled atmosphere (CA) plant and shelf-life of fresh tomatoes at different storage conditions were studied in this research. The controlled chamber (4.5' × 4.5' × 4.5') with ... Development of a controlled atmosphere (CA) plant and shelf-life of fresh tomatoes at different storage conditions were studied in this research. The controlled chamber (4.5' × 4.5' × 4.5') with supplement of 1% L-ascorbic acid as antioxidant source was constructed using locally available materials. Fresh tomatoes were kept with wrapping by low density polyethylene under refrigerated and CA storage conditions. The maximum shelf-life of fresh tomato was 42 days under CA condition and followed by 35 days in refrigeration condition. Though initial cost of controlled atmosphere was high but it resulted in maximum shelf life of tomato. However, CA condition retained the physiological changes namely, color change, TSS, and weight loss of fresh tomatoes than that of stored in refrigerated condition. From nutritional point of view, it was concluded that developed CA plant could be used to extend the shelf-life of fresh tomatoes with minimum physico-chemical changes throughout the storage period. 展开更多
关键词 controlled atmosphere TOMATO Shelf-Life Storage Study Weight Loss
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Use of Total Precipitable Water Classification of A Priori Error and Quality Control in Atmospheric Temperature and Water Vapor Sounding Retrieval 被引量:4
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作者 Eun-Han KWON Elisabeth WEISZ 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第2期263-273,共11页
This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared ... This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared (IR) sounders. Temperature and water vapor profiles are retrieved from Atmospheric InfraRed Sounder (AIRS) radiance measurements by applying a physical iterative method using regression retrieval as the first guess. Based on the dependency of first-guess errors on the degree of atmospheric moistness, the a priori first-guess errors classified by total precipitable water (TPW) are applied in the AIRS physical retrieval procedure. Compared to the retrieval results from a fixed a priori error, boundary layer moisture retrievals appear to be improved via TPW classification of a priori first-guess errors. Six quality control (QC) tests, which check non-converged or bad retrievals, large residuals, high terrain and desert areas, and large temperature and moisture deviations from the first guess regression retrieval, are also applied in the AIRS physical retrievals. Significantly large errors are found for the retrievals rejected by these six QCs, and the retrieval errors are substantially reduced via QC over land, which suggest the usefulness and high impact of the QCs, especially over land. In conclusion, the use of dynamic a priori error information according to atmospheric moistness, and the use of appropriate QCs dealing with the geographical information and the deviation from the first-guess as well as the conventional inverse performance are suggested to improve temperature and moisture retrievals and their applications. 展开更多
关键词 atmospheric sounding AIRS total precipitable water a priori error quality control
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Experimental Study on Surface Dielectric Barrier Discharge Plasma Actuator with Different Encapsulated Electrode Widths for Airflow Control at Atmospheric Pressure 被引量:4
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作者 齐晓华 杨亮 +3 位作者 闫慧杰 金英 滑跃 任春生 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第10期1005-1011,共7页
The surface dielectric barrier discharge (SDBD) plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study t... The surface dielectric barrier discharge (SDBD) plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study the airflow acceleration behavior. The effects of encapsulated electrode width on the actuator performance are experimentally investigated by measuring the dielectric layer surface potential, time-averaged ionic wind velocity and thrust force. Experimental results show that the airflow velocity and thrust force increase with the encapsulated electrode width. The results can be attributed to the distinct plasma distribution at different encapsulated electrode widths. 展开更多
关键词 atmospheric pressure discharge plasma surface dielectric barrier discharge(SDBD) flow control encapsulated electrode width Schlieren visualization
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Ultra-precision machining of cerium-lanthanum alloy with atmosphere control in an auxiliary device
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作者 Chenyu Zhao Shengjie Wu Min Lai 《Nanotechnology and Precision Engineering》 CAS CSCD 2022年第3期30-35,共6页
Cerium–lanthanum alloys are the main component of nickel–metal hydride batteries,and they are thus an important material in the greenenergy industry.However,these alloys have very strong chemical activity,and their ... Cerium–lanthanum alloys are the main component of nickel–metal hydride batteries,and they are thus an important material in the greenenergy industry.However,these alloys have very strong chemical activity,and their surfaces are easily oxidized,leading to great difficulties in their application.To improve the corrosion resistance of cerium–lanthanum alloys,it is necessary to obtain a nanoscale surface with low roughness.However,these alloys can easily succumb to spontaneous combustion during machining.Currently,to inhibit the occurrence of fire,machining of this alloy in ambient air needs to be conducted at very low cutting speeds while spraying the workpiece with a large amount of cutting fluid.However,this is inefficient,and only a very limited range of parameters can be optimized at low cutting speeds;this restricts the optimization of other cutting parameters.To achieve ultraprecision machining of cerium–lanthanum alloys,in this work,an auxiliary machining device was developed,and its effectiveness was verified.The results show that the developed device can improve the cutting speed and obtain a machined surface with low roughness.The device can also improve the machining efficiency and completely prevent the occurrence of spontaneous combustion.It was found that the formation of a build-up of swarf on the cutting tool is eliminated with high-speed cutting,and the surface roughness(Sa)can reach 5.64 nm within the selected parameters.Finally,the oxidation processes of the cerium–lanthanum alloy and its swarf were studied,and the process of the generation of oxidative products in the swarf was elucidated.The results revealed that most of the intermediate oxidative products in the swarf were Ce^(3+),there were major oxygen vacancies in the swarf,and the final oxidative product was Ce^(4+). 展开更多
关键词 Cerium–lanthanum alloy Ultraprecision machining Surface roughness atmosphere control
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Atmospheric Environmental Capacity of S_2 in Winter over Lanzhou in China:A Case Study 被引量:9
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作者 安兴琴 左洪超 陈丽娟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期688-699,共12页
The total emission control method based on atmospheric environmental capacity is the most effective in air pollution mitigation. The atmospheric environmental capacities of SO2 on representative days over Lanzhou are ... The total emission control method based on atmospheric environmental capacity is the most effective in air pollution mitigation. The atmospheric environmental capacities of SO2 on representative days over Lanzhou are estimated using the numerical models RAMS, HYPACT and a linear programming model, according to the national ambient air quality standard of China (NAAQSCHN). The results show that the fields of meteorological elements and SO2 simulated by the models agree reasonably well with observations. The atmospheric environmental capacity of SO2 over Lanzhou is around 111.7 × 10^3 kg d^-1, and in order to meet the air quality level Ⅱ of the NAAQSCHN, SO2 emissions need to be reduced by 20%. 展开更多
关键词 air pollution total emission control method atmospheric environmental capacity air quality standard numerical simulation
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Effects of Different Atmospheres on the Postharvest Physiology and Quality of the Sweet Cherry 被引量:2
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作者 JIANG Ai-li, TIAN Shi-ping, XU Yong, WANG Yi and FAN Qing(Institute of Botany, Chinese Academy of Sciences , Beijing 100093 , P. R . China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第5期555-561,共7页
The changes in physiological characteristics, quality and storability of the sweet cherry (Pru-mus avium L. cv. Hongdeng) stored in controlled atmospheres (CA), in modified atmosphere packages (MAP) and in air (CK) we... The changes in physiological characteristics, quality and storability of the sweet cherry (Pru-mus avium L. cv. Hongdeng) stored in controlled atmospheres (CA), in modified atmosphere packages (MAP) and in air (CK) were investigated in this paper. The results showed that CA and MAP treatments significantly inhibited fruit rot and flesh browning, kept firmness and fruit color, reduced ethylene and ethanol content in pulp, slowed down the increase of polyphenol oxidase (PPO) and peroxidase (POD) activity and malondialdehyde (MDA) content in comparison with CK. Meanwhile, CA treatments showed a better benefit of reducing ethylene and ethanol contents, inhibiting PPO and POD activities, declining rot rate and browning index compared to MAP. The fruit could be stored in CA conditions for 60 days without any off-flavor. The sweet cherries kept in CA with 5% O2 + 10% CO2 showed a better storability than that in CA with 5% O2 + 5% CO2. 展开更多
关键词 Sweet cherry controlled atmosphere PHYSIOLOGY QUALITY
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Electrical features of radio-frequency atmospheric pressure helium discharge with and without dielectric electrodes 被引量:1
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作者 H ASHRAF S Z A SHAH +5 位作者 H I A QAZI M A KHAN S HUSSAIN M A BADAR S NIAZ M SHAFIQ 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第2期60-67,共8页
A comparative study of radio-frequency atmospheric pressure glow discharge(rf APGD)generated in helium with and without dielectric electrodes to investigate the effect of electrodes insulation on electrical features o... A comparative study of radio-frequency atmospheric pressure glow discharge(rf APGD)generated in helium with and without dielectric electrodes to investigate the effect of electrodes insulation on electrical features of APGD is presented. In the α mode, both the rf APGDs remain volumetric, stable and uniform. In the γ mode, the APGD without dielectric electrodes shrinks into a constricted plasma column whereas APGD with dielectric electrodes remains stable and retains the same volume without plasma constriction even at higher densities of discharge current. A comparison of electrical features of both rf APGDs in normal and abnormal glow discharge regimes is presented. In both APGDs with and without dielectric electrodes,impedance measurements have been performed and compared with equivalent circuit models.The measured impedance data is found to be in good agreement with simulated data. 展开更多
关键词 RADIOFREQUENCY atmospheric pressure GLOW DISCHARGE DIELECTRIC ELECTRODES plasma stability control
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Study on the Total Amount Control of Atmospheric Pollutant Based on GIS 被引量:1
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作者 JIAN-PING WANG XI-KUN GUO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第4期233-237,共5页
To provide effective environmental management for total amount control of atmospheric pollutants. Methods An atmospheric diffusion model of sulfur dioxide on the surface of the earth was established and tested in Shan... To provide effective environmental management for total amount control of atmospheric pollutants. Methods An atmospheric diffusion model of sulfur dioxide on the surface of the earth was established and tested in Shantou of Guangdong Province on the basis of an overall assessment of regional natural environment, social economic state of development, pollution sources and atmospheric environmental quality. Compared with actual monitoring results in a studied region, simulation values fell within the range of two times of error and were evenly distributed in the two sides of the monitored values. Predicted with the largest emission model method, the largest emission of sulfur dioxide would be 54 279.792 tons per year in 2010. Conclusion The mathematical model established and revised on the basis of GIS is more rational and suitable for the regional characteristics of total amount control of air pollutants. 展开更多
关键词 Total amount control of atmospheric pollutants atmospheric diffusion model Pollution source GIS
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VARIABLE STRUCTURE CONTROL OF AIRCRAFTFOR ATMOSPHERIC DISTURBANCE
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作者 Zhu Xiaoping Zhou Zhou(Nanjing University of Aeronautics and Astronautics, Nanjing, China, 210016)Chen Shilu(Northwestern Polytechnical University, Hi’an, China, 710072) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1995年第4期247-255,共9页
Variable structure control (VSC) applied to atmospheric disturbance sup-pression is presented. The conditions are stipulated: the sliding mode existenee condi-tion, and invanance condition of atmospheric disturbanee i... Variable structure control (VSC) applied to atmospheric disturbance sup-pression is presented. The conditions are stipulated: the sliding mode existenee condi-tion, and invanance condition of atmospheric disturbanee in the variable structuresystem (VSS). A method of eigenstructure assignment technique for switching surfaeedesign is proposed. Based on different atmospheric disturbanee characteristics, such asrandom turbulence, discrete gust and wind shear, two kinds of control laws are derived that possess strong robustness. An example shows that this control approach isfeasible and effective. 展开更多
关键词 atmosphereS disturbances variable geometry structures control air-craft
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Quality control for bloom casting of YQ450NQR1 steel
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作者 Yong Chen Guo-rong Wu Miao-yong Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第1期32-36,共5页
To reduce surface depression of a bloom, the primary cooling intensity was decreased, and the water distribution of mold wide and narrow faces was optimized. The length of secondary cooling zones and the specific wate... To reduce surface depression of a bloom, the primary cooling intensity was decreased, and the water distribution of mold wide and narrow faces was optimized. The length of secondary cooling zones and the specific water flow were increased, and the water flow distribution among the secondary cooling zones was adjusted to eliminate central defects, such as center looseness, central segregation, and center line cracks. The operation showed that the proportion of surface depression decreased from 37.22% to 2.87%, whereas the proportion of center looseness for 〈1.0 increased from 79.71% to 90.70%, the proportion of central segregation for 〈0.5 increased from 1.45% to 44.19%, and the proportion of center line cracks that are free increased from 39.13% to 62.79%. The qualified blooms are delivered to produce 310 Z-beam, whose yield strength is greater than 450 MPa. 展开更多
关键词 corrosion resistant steel atmospheric corrosion bloom casting primary cooling secondary cooling quality control
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Optimal Control for Smokescreen Release Based on Numerical Simulation: Challenges and Theoretical Framework
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作者 Cheng Cui Sheng Xu +3 位作者 Zhihua Zhu Feng Liu Xuezheng Zhu Shunxiang Huang 《Advances in Chemical Engineering and Science》 2015年第2期158-163,共6页
This paper analyses the key issues and challenges of the smokescreen release optimal control under complex terrains and meteorological conditions, and proposes a dynamic model based theoretical framework that integrat... This paper analyses the key issues and challenges of the smokescreen release optimal control under complex terrains and meteorological conditions, and proposes a dynamic model based theoretical framework that integrates the smoke release equipments, the release time, the release positions, different ways to release smoke and launch attacks, various terrains and meteorological conditions and other factors so as to determine the appropriate smokescreen release plans through the rapid inverse for various threats and battlefield environments and to conduct realtime simulation and evaluation. This paper provides a theoretical basis for the smokescreen release optimal control. 展开更多
关键词 NUMERIcaL Simulation atmospherIC DISPERSION Smokescreen Optimal control
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Atmospheric Carbon Dioxide Reconstruction and Ocean Acidification Deduced from Carbon Isotope Variations across the Triassic–Jurassic Boundary in the Qiangtang Area, Tibetan Plateau
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作者 YI Fan YI Haisheng +1 位作者 XIA Guoqing CAI Zhanhu 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期2055-2057,共3页
Objective The end-Triassic mass extinction was one of the five most profound Phanerozoic extinction events.This event was accompanied by a series of significant environmental changes,of which the most notable is the e... Objective The end-Triassic mass extinction was one of the five most profound Phanerozoic extinction events.This event was accompanied by a series of significant environmental changes,of which the most notable is the emergence of warm climate and the world-wide disappearance of carbonate platform. 展开更多
关键词 PCO ca Jurassic Boundary in the Qiangtang Area Tibetan Plateau atmospheric carbon Dioxide Reconstruction and Ocean Acidification Deduced from carbon Isotope Variations across the Triassic
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Atmospheric Pollution Control Effect of Key Cities in Inner Mongolia in 2014
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作者 song guiying jiang jing +2 位作者 hou ting di hui chen yungang 《Meteorological and Environmental Research》 CAS 2016年第2期5-11,共7页
APEC conference was held in Beijing during November 3- 12,2014. Hohhot City and Baotou City fall into the peripheral key air pollution control cities in the " Beijing- Tianjin- Hebei" region. Inner Mongolia governme... APEC conference was held in Beijing during November 3- 12,2014. Hohhot City and Baotou City fall into the peripheral key air pollution control cities in the " Beijing- Tianjin- Hebei" region. Inner Mongolia government adopted powerful pollution control measures in the period of the conference. According to pollutant concentration data and meteorological data etc. in the course of the event and the same period of last year,the atmospheric pollution variations and control effect were discussed in this study. The results showed that during October 1- 25,2014,there were 16 days with air pollution in Hohhot City and 15 days with air pollution in Baotou City,respectively increasing by 8% and 34% compared with the same period of 2013,and the concentration of particulate matter was also higher than that of last year. During October 22- 24,2014,Hohhot and Baotou cities were polluted persistently. The variation features of hourly concentration of main pollutants PM(10) and PM2. 5were similar to those in the same period of 2013. That is,the pollutant concentration reached the maximum from 21:00 to 23:00,and the minimum appeared from 15: 00 to 19: 00 in the next day. In the course of the event,the concentration of particulate matter in the two cities stared to reduce greatly on October 26. From October 26 to November 13,there were no days with air pollution in Hohhot City,decreasing by 100% compared with the same period of 2013; there were five days with air pollution in Baotou City,and the numbers of days with slight,moderate and severe pollution reduced by 37%,100% and67% respectively compared with the same period of last year. The persistent air pollution from October 22 to the first 10 days of November was related to unfavorable meteorological conditions,and the meteorological condition in the same period of 2014 was even worse. In the course of the event,the Inner Mongolia Government adopted air pollution control measures around October 25 and began to adopt some powerful pollution control measures on November 1. As a result,air pollution in key cities has been controlled effectively. This event showed that urban atmospheric pollution problem can be resolved,and we should take an optimistic attitude towards this matter. 展开更多
关键词 atmospheric pollution variation control effect Hohhot City Baotou City The period of APEC conference China
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