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Impacts of high temperature,relative air humidity,and vapor pressure deficit on the seed set of contrasting maize genotypes during flowering
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作者 Xin Dong Baole Li +8 位作者 Zhenzhen Yan Ling Guan Shoubing Huang Shujun Li Zhiyun Qi Ling Tang Honglin Tian Zhongjun Fu Hua Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期2955-2969,共15页
Heat stress is a major constraint to current and future maize production at the global scale.Male and female reproductive organs both play major roles in increasing seed set under heat stress at flowering,but their re... Heat stress is a major constraint to current and future maize production at the global scale.Male and female reproductive organs both play major roles in increasing seed set under heat stress at flowering,but their relative contributions to seed set are unclear.In this study,a 2-year field experiment including three sowing dates in each year and 20 inbred lines was conducted.Seed set,kernel number per ear,and grain yield were all reduced by more than 80%in the third sowing dates compared to the first sowing dates.Pollen viability,silk emergence ratio,and anthesis-silking interval were the key determinants of seed set under heat stress;and their correlation coefficients were 0.89^(***),0.65^(***),and-0.72^(***),respectively.Vapor pressure deficit(VPD)and relative air humidity(RH)both had significant correlations with pollen viability and the silk emergence ratio.High RH can alleviate the impacts of heat on maize seed set by maintaining high pollen viability and a high silk emergence ratio.Under a warming climate from 2020 to 2050,VPD will decrease due to the increased RH.Based on their pollen viability and silk emergence ratios,the 20 genotypes fell into four different groups.The group with high pollen viability and a high silk emergence ratio performed better under heat stress,and their performance can be further improved by combining the improved flowering pattern traits. 展开更多
关键词 MAIZE pollen viability silk emergence heat stress relative humidity
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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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Effect of Humidity on Formaldehyde Oxidation over Ce_(0.8)Zr_(0.2)O_(y)Catalyst
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作者 TANG Ruijiu YANG Zonglin +4 位作者 LIU Xiang JIA Lijuan WANG Fang DUAN Kaijiao LIU Tiancheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1108-1115,共8页
In the preparation of a series of Ce_(0.8)Zr_(0.2)O_(y)catalysts catalyzing the removal of formaldehyde,BET,H2-TPR,IR,SEM,XPS,and XRD were used to characterize the catalyst,and the influence of humidity on the catalys... In the preparation of a series of Ce_(0.8)Zr_(0.2)O_(y)catalysts catalyzing the removal of formaldehyde,BET,H2-TPR,IR,SEM,XPS,and XRD were used to characterize the catalyst,and the influence of humidity on the catalyst activity was studied by adjusting the humidity during the process.The experimental results showed that the formaldehyde removal rate increased with the increase of humidity.When the humidity was higher than 50%,the formaldehyde removal rate decreased by 3%over that when the humidity was 50%.The characterization results showed that humidity facilitated the activation of oxygen and the formation of hydroxyl groups,which both promoted the formation and oxidative decomposition of intermediates and prevented the deposition of intermediates that clogged the pores,allowing more formaldehyde to be adsorbed and oxidized,which increased the activity of the catalyst.This provides new mechanistic evidence for the oxidation of formaldehyde and helps in the development of relatively low-cost materials for formaldehyde purification. 展开更多
关键词 FORMALDEHYDE humidity Ce_(0.8)Zr_(0.2)O_(y) catalytic oxidation
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Modelling of the variation of granular base materials resilient modulus with material characteristics and humidity conditions
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作者 Jean-Pascal Bilodeau Erdrick Leandro Perez-Gonzalez Ali Saeidi 《Journal of Road Engineering》 2024年第1期27-35,共9页
This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal analyses.The fines... This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal analyses.The fines content and the percentage of fractured coarse aggregates were identified as direct indicators of the resilient modulus susceptibility to changes in water content.The results showed that the percentage of fractured coarse aggregates particles(FR)has a more significant impact on the resilient modulus(Er)of crushed granular materials used in pavement construction than the combined indicator of the fines content and sample volumetrics(nf).Crushed granular materials with a higher percentage of fractured coarse aggregates are relatively insensitive to changes in the degree of saturation,but become more sensitive as the fine fraction porosity decreases.An adjusted model was proposed based on the existing formulation,but considers a complex parameter to describe and adjust the sensitivity of base granular materials to variations in moisture content with respect to fabrication charac-teristics,fines content and volumetric properties.The model shows that the variation of Er values is below10%for fully crushed granular materials.However,it reaches approximately±12%for materials with 75%of crushed coarse aggregates andþ40%and-25%for materials with FR=50%.This model could help select good ag-gregates characteristics and adjust grain-size distribution for environments where significant moisture content variations can occur in the pavement system,such as in the Province of Quebec(Canada).As it is based on pa-rameters that can be easily determined or estimated,it also represents a valuable tool for detailed design and analysis that can consider material characteristics. 展开更多
关键词 Resilient modulus Degree of saturation humidity conditions Unbound granular materials Pavement base
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Prediction of Low Heating Value of Sugar Cane Bagasse as a Fuel for Industrial Boilers in the High Relative Humidity Region: Case of Cameroon
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作者 Pierre Kana-Donfack Maxell Tientcheu-Nsiewe +1 位作者 Denis Tcheukam-Toko César Kapseu 《Open Journal of Applied Sciences》 2024年第6期1604-1624,共21页
Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised o... Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised on the applicability of these equations in different parts of the globe. This study was initiated to tackle these problems and also check the most suited mathematical models for the Law Heating Value of Cameroonian bagasse. Data and bagasse samples were collected at the Cameroonian sugarcane factory. The effects of cane variety, age of harvesting, source, moisture content, and sucrose on the LHV of Cameroon bagasse have been tested. It was shown that humidity does not change within a variety, but changes from the dry season to the rainy season;the sugar in the rainy season is significantly different from that collected in the dry season. Samples of the same variety have identical LHV. LHV in the dry season is significantly different from LHV in the rainy season. According to the fact that this study was done for cane with different ages of harvesting, the maturity of Cameroonian sugarcane does not affect LHV of bagasse. Tree selected models are much superior tool for the prediction of the LHV for bagasse in Cameroon compared to others. The standard deviation of these validated models is around 200 kJ/kg compared to the experimental. Thus, the models determined in foreign countries, are not necessarily applicable in predicting the LHV of bagasse in other countries with the same accuracy as that in their native country. There was linear relationship between humidity, ash and sugar content in the bagasse. It is possible to build models based on data from physical composition of bagasse using regression analysis. 展开更多
关键词 Sugarcane Bagasse Relative humidity ASH Low Heating Value
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Laser direct writing of Ga_(2)O_(3)/liquid metal-based flexible humidity sensors 被引量:5
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作者 Songya Cui Yuyao Lu +5 位作者 Depeng Kong Huayu Luo Liang Peng Geng Yang Huayong Yang Kaichen Xu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第7期30-39,共10页
Flexible and wearable humidity sensors play a vital role in daily point-of-care diagnosis and noncontact human-machine interactions.However,achieving a facile and high-speed fabrication approach to realizing flexible ... Flexible and wearable humidity sensors play a vital role in daily point-of-care diagnosis and noncontact human-machine interactions.However,achieving a facile and high-speed fabrication approach to realizing flexible humidity sensors remains a challenge.In this work,a wearable capacitive-type Ga_(2)O_(3)/liquid metal-based humidity sensor is demonstrated by a one-step laser direct writing technique.Owing to the photothermal effect of laser,the Ga_(2)O_(3)-wrapped liquid metal particles can be selectively sintered and converted from insulative to conductive traces with a resistivity of 0.19Ω·cm,while the untreated regions serve as active sensing layers in response to moisture changes.Under 95%relative humidity,the humidity sensor displays a highly stable performance along with rapid response and recover time.Utilizing these superior properties,the Ga_(2)O_(3)/liquid metal-based humidity sensor is able to monitor human respiration rate,as well as skin moisture of the palm under different physiological states for healthcare monitoring. 展开更多
关键词 laser direct writing liquid metal humidity sensors flexible electronics wearable sensors
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Outstanding Humidity Chemiresistors Based on Imine-Linked Covalent Organic Framework Films for Human Respiration Monitoring 被引量:3
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作者 Xiyu Chen Lingwei Kong +9 位作者 Jaafar Abdul-Aziz Mehrez Chao Fan Wenjing Quan Yongwei Zhang Min Zeng Jianhua Yang Nantao Hu Yanjie Su Hao Wei Zhi Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期368-383,共16页
Human metabolite moisture detection is important in health monitoring and non-invasive diagnosis.However,ultra-sensitive quantitative extraction of respiration information in real-time remains a great challenge.Herein... Human metabolite moisture detection is important in health monitoring and non-invasive diagnosis.However,ultra-sensitive quantitative extraction of respiration information in real-time remains a great challenge.Herein,chemiresistors based on imine-linked covalent organic framework(COF)films with dual-active sites are fabricated to address this issue,which demonstrates an amplified humidity-sensing signal performance.By regulation of monomers and functional groups,these COF films can be pre-engineered to achieve high response,wide detection range,fast response,and recovery time.Under the condition of relative humidity ranging from 13 to 98%,the COFTAPB-DHTA film-based humidity sensor exhibits outstanding humidity sensing perfor-mance with an expanded response value of 390 times.Furthermore,the response values of the COF film-based sensor are highly linear to the relative humidity in the range below 60%,reflecting a quantitative sensing mechanism at the molecular level.Based on the dual-site adsorption of the(-C=N-)and(C-N)stretching vibrations,the revers-ible tautomerism induced by hydrogen bonding with water molecules is demonstrated to be the main intrinsic mechanism for this effective humidity detection.In addition,the synthesized COF films can be further exploited to effectively detect human nasal and oral breathing as well as fabric permeability,which will inspire novel designs for effective humidity-detection devices. 展开更多
关键词 Covalent organic frameworks humidity sensors Reversible tautomerism Non-invasive diagnosis Health monitoring
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Functionalized Hydrogel-Based Wearable Gas and Humidity Sensors 被引量:1
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作者 Yibing Luo Jianye Li +3 位作者 Qiongling Ding Hao Wang Chuan Liu Jin Wu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期103-147,共45页
Breathing is an inherent human activity;however,the composition of the air we inhale and gas exhale remains unknown to us.To address this,wearable vapor sensors can help people monitor air composition in real time to ... Breathing is an inherent human activity;however,the composition of the air we inhale and gas exhale remains unknown to us.To address this,wearable vapor sensors can help people monitor air composition in real time to avoid underlying risks,and for the early detection and treatment of diseases for home healthcare.Hydrogels with three-dimensional polymer networks and large amounts of water molecules are naturally flexible and stretchable.Functionalized hydrogels are intrinsically conductive,self-healing,self-adhesive,biocompatible,and room-temperature sensitive.Compared with traditional rigid vapor sensors,hydrogel-based gas and humidity sensors can directly fit human skin or clothing,and are more suitable for real-time monitoring of personal health and safety.In this review,current studies on hydrogel-based vapor sensors are investigated.The required properties and optimization methods of wearable hydrogel-based sensors are introduced.Subsequently,existing reports on the response mechanisms of hydrogel-based gas and humidity sensors are summarized.Related works on hydrogel-based vapor sensors for their application in personal health and safety monitoring are presented.Moreover,the potential of hydrogels in the field of vapor sensing is elucidated.Finally,the current research status,challenges,and future trends of hydrogel gas/humidity sensing are discussed. 展开更多
关键词 Health and safety monitoring Gas and humidity sensor Functionalized hydrogel Wearable sensor Flexible and stretchable sensor
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Experimental investigation on degradation mechanism of membrane electrode assembly at different humidity under automotive protocol
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作者 Jiajun Wang Wenbin Yang +2 位作者 Jiangtao Geng Zhigang Shao Wei Song 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期70-79,共10页
Humidity can affect the attenuation of MEA(membrane electrode assembly), however, the relationship between humidity and MEA decays is complex and ambiguous in realistic application. Herein, we design a simulating auto... Humidity can affect the attenuation of MEA(membrane electrode assembly), however, the relationship between humidity and MEA decays is complex and ambiguous in realistic application. Herein, we design a simulating automotive protocol, performed on five single fuel cells under RH(relative humidity) 100%,RH 80%, RH 64%, and RH 40%, RH 10%, respectively, to study the relationship of MEA decays and humidity and suggest optimized humidity range to extend the durability. With the electrochemical impedance spectroscopy, cyclic voltammetry, X-ray fluorescence, X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, the four degradation mechanisms about catalyst layer, including Pt dissolution, Pt coarsening, carbon corrosion and ionomer degradation, are observed. Pt coarsening and carbon corrosion are accelerated by higher water content at high humidity. Ionomer degradation and Pt dissolution are enhanced in low humidity. With the linear sweep voltammetry, ion chromatography,nuclear magnetic resonance, tensile test and scan electron microscope, chemical and mechanical degradation in proton exchange membrane are all observed in these five fuels. Chemical degradation, characterized by membrane thinning and more fluoride loss, occurred markedly in RH 10%. Mechanical degradation, characterized by the non-uniformity thickness and bad mechanical properties, is more pronounced in RH 100%, RH 80%, RH 64%. These two degradations are in a moderate level in RH 40%. The research suggests that the RH range from 64% to 40% is conductive to mitigate the degradation of MEAs operated in automotive applications. 展开更多
关键词 Fuel cell Simulating automotive protocol Relative humidity Degradation MEMBRANE
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Combined effects of temperature and humidity on the interaction between tomato and Botrytis cinerea revealed by integration of histological characteristics and transcriptome sequencing
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作者 Tianzhu Li Jie Zhou Jianming Li 《Horticulture Research》 SCIE CSCD 2023年第2期53-64,共12页
The environment significantly impacts the interaction between plants and pathogens,thus remarkably affecting crop disease occurrence.However,the detailed combined mechanisms of temperature and humidity influencing thi... The environment significantly impacts the interaction between plants and pathogens,thus remarkably affecting crop disease occurrence.However,the detailed combined mechanisms of temperature and humidity influencing this interaction remain unclear.In this study,the interaction between tomato and Botrytis cinerea in various temperature and humidity conditions was analyzed by histological observation and a dual RNA-seq approach.Results showed that low humidity was not favorable for mycelial growth,resulting in infection failure.Both high and low temperatures at high humidity successfully inhibited pathogenic infection and disease incidence in the tomato plants,thus enhancing their resistance to B.cinerea.The high temperature and high humidity(HH)treatment induced the upregulation of light reaction genes,increased the net photosynthetic rate,and expanded the chloroplast morphology of infected tomatoes.The HH treatment also inhibited the expression of cell cycle-related genes of B.cinerea,interfered with conidial germination andmycelial growth,and damagedmycelial cell structure.Lowtemperature and high humidity(LH)treatment induced the expression of cell wall modification genes and remodeled the cell wall morphology of tomatoes in response to B.cinerea.In addition,the downregulated fungal catabolic genes and the abnormal increase in electron density ofmycelial cells under LH treatment subsequently reduced the infection ability of B.cinerea.These results further explain the coupled effects of temperature and humidity on plant defenses and pathogen virulence,and provide a potential means to control gray mold. 展开更多
关键词 inhibited HISTOLOGICAL humidity
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Short Communication: Enhancing the Drying Process of Microbial-Based Products with a Dehumidifier
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作者 Nor Hidayah Bohari Elya Masya Mohd Fishal +2 位作者 Ili Bazilah Abd Razak Muhammad Ashraf Arif Mohd Nasir Cik Mohd Rizuan Zainal Abidin 《Advances in Microbiology》 CAS 2024年第6期333-339,共7页
The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, c... The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, cost-effectiveness, and a prolonged shelf life. Controlling the drying process is crucial for ensuring the stability and durability of the product. The traditional approach, which involved mechanical and natural drying, led to decreased productivity and quality. The objective of this research endeavour was to achieve a dry process enhancement while preserving the microbial quality of Trichoderma asperellum (M103). The temperature and relative humidity during the drying period were monitored under two conditions: with and without a dehumidifier. The results demonstrate that the dehumidifier increases drying period efficiency by up to 63%. 展开更多
关键词 DEhumidIFIER DRYING Relative humidity Microbial-Based Product
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Clinical Observation of the Hot and Humid Compress Therapy of Traditional Chinese Medicine in the Treatment of Qi Stagnation and Blood Stasis Type of Lumbar Disc Herniation
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作者 Hailin Song Kui Xu +3 位作者 Hong Zhu Zengwu Xu Peng Li Runkai Wang 《Open Journal of Orthopedics》 2024年第7期312-324,共13页
Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis,... Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis, clinical evidence is limited. Objective: The purpose of this study is to provide high-quality evidence to support the effectiveness of the traditional Chinese hot and humid compress in the treatment of LDH with qi stagnation and blood stasis. Methods: From October 2021 to November 2023, 86 patients with LDH of qi stagnation and blood stasis type were recruited in our hospital and divided into a control (n = 43) and an observation group (n = 43) according to the random number table method. The control group was given routine clinical treatment, and the observation group was treated with the hot and humid compress therapy for two weeks. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, TCM syndrome score, serum interleukin-6 (IL-6), serum interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were observed and compared between the two groups before and after treatment, and the clinical efficacy of the two groups was evaluated. Results: After treatment, the VAS score, TCM symptom score, and serum IL-6, IL-1β, and TNF-α levels decreased in both groups (P P P P P Conclusions: The hot and humid compress of traditional Chinese medicine can effectively relieve pain, restore lumbar function, improve TCM syndromes, reduce the level of inflammatory factors, and have a curative effect in treating LDH. 展开更多
关键词 Chinese Medicine Hot and humid Compress Lumbar Disc Herniation Qi Stagnation and Blood Stasis Type TCM Symptom Score Clinical Efficacy
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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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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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Analysis on the Climate Characteristics of Relative Humidity in Recent 40 Years in Urumqi City 被引量:2
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作者 李瑞 柳芳 +1 位作者 冉桂平 杨霞 《Meteorological and Environmental Research》 CAS 2010年第8期21-23,26,共4页
By using the daily average relative humidity data in Urumqi during 1961-2000,the basic climate characteristics and the variation trend of relative humidity in Urumqi in recent 40 years were analyzed.The results showed... By using the daily average relative humidity data in Urumqi during 1961-2000,the basic climate characteristics and the variation trend of relative humidity in Urumqi in recent 40 years were analyzed.The results showed that the yearly average relative humidity in Urumqi was 57.5%.The relative humidity in winter was 77.5% which was the biggest all the year round,and the relative humidity in summer was 41.2% which was the smallest.The relative humidity in spring,summer,autumn,winter and the yearly relative humidity all displayed the increase trend.The yearly mean relative humidity had the periods of mainly 2,3-4 and quasi-7 years.The periodic oscillation of quasi-7 years was the strongest. 展开更多
关键词 Relative humidity Climate variation Wavelet analysis Urumqi City China
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Retrieval and analysis of sea surface air temperature and relative humidity
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作者 伍玉梅 He Yijun Shen Hui 《High Technology Letters》 EI CAS 2015年第1期102-108,共7页
Air temperature and relative humidity have been the main parameters of meteorology study. In the past data could be obtained from in-situ observations, but the observations are local and sparse, especially over ocean.... Air temperature and relative humidity have been the main parameters of meteorology study. In the past data could be obtained from in-situ observations, but the observations are local and sparse, especially over ocean. Now we can get them from satellites, yet it is hard to estimate them from sat- ellites directly so far. This paper presents a new method to retrieve monthly averaged sea air temper- ature (SAT) and relative humidity (RH) near sea surface from satellite data with artificial neural networks (ANN). Compared with the observations in Pacific and Atlantic, the root mean square (RMS) and the correlation between the estimated SAT and the observations are about 0.91 ~C and 0.99, respectively. The RMS and the correlation of RH are about 3.73% and 0.65, respectively. Compared with the multiple regression method, the ANN methodology is more powerful in building nonlinear relations in this research. Thus the global monthly average SAT and RH are retrieved from the fixed ANN network from July 1987 to May 2004. In general the annual average SAT shows the increasing trend in recent 18 years. The abnormality of SAT is decomposed with the empirical or- thogonal function (EOF). The leading three EOFs could explain 84% of the total variation. EOF1 (76.1%) presents the seasonal change of the SAT abnormality. EOF2 (4.6%) is mainly related with ENSO. EOF3 (3.3%) shows some new interesting phenomena appearing in the three main currents in Pacific, Atlantic and Indian Ocean. 展开更多
关键词 sea surface air temperature relative humidity( RH) artificial neural network (ANN) empirical orthogonal function(EOF)
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Factors affecting relative humidity during wood vacuum drying 被引量:1
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作者 肖辉 蔡英春 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期165-167,I0004,共4页
Effects of pressure and temperature in the chamber during vacuum drying on the relative humidity and evaporation of wood surface were investigated by using the vacuum chamber. The setting temperature during vacuum dry... Effects of pressure and temperature in the chamber during vacuum drying on the relative humidity and evaporation of wood surface were investigated by using the vacuum chamber. The setting temperature during vacuum drying included dry-bulb temperature ta, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the cooling water in the condenser. Results indicated that relative humidity during vacuum drying was affected by the dry-bulb temperature td, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the water in the condenser. Relative humidity of wood decreased with the increase in temperature at the given temperature of the water in the condenser. The relative humidity was affected slightly by pressure in the vacuum chamber pA, and it decreased from 70% to 65% with pA increased from 50 kPa to 101 kPa. Moreover, there was nearly no evaporation under the vacuum without external heating. 展开更多
关键词 influencing factors radio frequency relative humidity wood vacuum drying
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Homogenized Daily Relative Humidity Series in China during 1960?2017 被引量:11
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作者 Zhen LI Zhongwei YAN +2 位作者 Yani ZHU Nicolas FREYCHET Simon TETT 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第4期318-327,共10页
Surface relative humidity(RH)is a key element for weather and climate monitoring and research.However,RH is not as commonly applied in studying climate change,partly because the observation series of RH are prone to i... Surface relative humidity(RH)is a key element for weather and climate monitoring and research.However,RH is not as commonly applied in studying climate change,partly because the observation series of RH are prone to inhomogeneous biases due to non-climate changes in the observation system.A homogenized dataset of daily RH series from 746 stations in Chinese mainland for the period 1960–2017,ChinaRHv1.0,has been developed.Most(685 or 91.82%of the total)station time series were inhomogeneous with one or more break points.The major breakpoints occurred in the early 2000s for many stations,especially in the humid and semi-humid zones,due to the implementation of automated observation across the country.The inhomogeneous biases in the early manual records before this change are positive relative to the recent automatic records,for most of the biased station series.There are more break points detected by using the MASH(Multiple Analysis of Series for Homogenization)method,with biases mainly around?0.5%and 0.5%.These inhomogeneous biases are adjusted with reference to the most recent observations for each station.Based on the adjusted observations,the regional mean RH series of China shows little long-term trend during 1960–2017[0.006%(10 yr)^?1],contrasting with a false decreasing trend[?0.414%(10 yr)?1]in the raw data.It is notable that ERA5 reanalysis data match closely with the interannual variations of the raw RH series in China,including the jump in the early 2000s,raising a caveat for its application in studying climate change in the region. 展开更多
关键词 RELATIVE humidity HOMOGENIZATION OBSERVATION system changes MASH(Multiple Analysis of SERIES for Homogenization)
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Intercomparison of Humidity and Temperature Sensors:GTS1, Vaisala RS80, and CFH 被引量:21
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作者 卞建春 陈洪滨 +3 位作者 Holger VMEL 段云俊 宣越健 吕达仁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第1期139-146,共8页
GTS1 digital radiosonde, developed by the Shanghai Changwang Meteorological Science and Technology Company in 1998, is now widely used in operational radiosonde stations in China. A preliminary comparison of simultane... GTS1 digital radiosonde, developed by the Shanghai Changwang Meteorological Science and Technology Company in 1998, is now widely used in operational radiosonde stations in China. A preliminary comparison of simultaneous humidity measurements by the GTS1 radiosonde, the Vaisala RS80 radiosonde, and the Cryogenic Frostpoint Hygrometer (CFH), launched at Kunming in August 2009, reveals a large dry bias produced by the GTS1 humidity sensor. The average relative dry bias is in the order of 10% below 500 hPa, increasing rapidly to 30% above 500 hPa, and up to 55% at 310 hPa. A much larger dry bias is observed in the daytime, and this daytime effect increases with altitude. The GTS1 radiosonde fails to respond to humidity changes in the upper troposphere, and sometimes even in the middle troposphere. The failure of GTS1 in the middle and upper troposphere will result in significant artificial humidity shifts in radiosonde climate records at stations in China where a transition from mechanical to digital radiosondes has occurred. A comparison of simultaneous temperature observations by the GTS1 radiosonde and the Vaisala RS80 radiosonde suggests that these two radiosondes provide highly reproducible temperature measurements in the troposphere, but produce opposite biases for daytime and nighttime measurements in the stratosphere. In the stratosphere, the GTS1 shows a warm bias (〈0.5 K) in the daytime and a relatively large cool bias (-0.2 K to -1.6 K) at nighttime. 展开更多
关键词 GTS1 radiosonde humidity dry bias
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Tomato Leaf Photosynthetic Responses to Humidity andTemperature Under Salinity and Water Deficit 被引量:12
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作者 H.L.XU L.GAUTHIER 《Pedosphere》 SCIE CAS CSCD 1999年第2期105-112,共8页
Greenhouse tomato plants (Lycopersicon esculentum Mill cv. Capello) were grown on peat-based substrate and treated with high (4.5 mS cm-1) and low (2.3 mS cm-1) nutrient solution electric conductivity(EC) under high a... Greenhouse tomato plants (Lycopersicon esculentum Mill cv. Capello) were grown on peat-based substrate and treated with high (4.5 mS cm-1) and low (2.3 mS cm-1) nutrient solution electric conductivity(EC) under high and low substrate water contents. FOur weeks after the beginning of the treatments, photosynthesis (Th) was measured under different humidity and temperatures to examine the interactive effectswith rhizosphere salinity and water deficit. A rectangular hyperbolic model fitted the light-photosynthesiscurve. Photosynthetic capacity (PC) was decreased but quantum yield (YQ) was increased by rhizospheresalinity caused by high EC. PN was decreased by low humidity only in high EC- and/or water-stressed plants.Under high photosynthetic photon flux (PPF), low humidity induced PC decline in water-stressed plants andPN oscillation in high-EC-treated plants. PN increased steadily as the leaf temperature changed from 18 Cto 23 and then decreased steadily from 23 to 38 . At 34 , PN decreased significantly in waterstressed plants. Dark respiration (RD) increased in an exponential manner as the leaf temperature changedfrom 18 to 38 to an extent about ten times higher under 38 than under 18 . Our data suggestedthat PN decrease under high temperature was attributed, st least in part, to the increased RD. RD in highEC- and/or water-stressed plants was higher than that in the plants of control under lower temperature butlower than that in the plants of control under high temperature. The analysis of stomatal and mesophyllconductance showed that low humidity effect was mainly through stomatal response while temperature effectwas mainly through biochemical functions. The result showed that environmental stresses affected PN in anadditive or synergistic manner. 展开更多
关键词 humidity PHOTOSYNTHESIS rhizosphere salinity TEMPERATURE water stress
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