The Impacts of Supplemental Irrigation Based on Soil Moisture Measurement and Nitrogen Use on Winter Wheat Yield and Nitrogen Absorption and Distribution

Based on split plot design method of field test,the impacts of supplemental irrigation based on soil moisture measurement and nitrogen use on winter wheat yield and nitrogen absorption and distribution were studied.Supplemental irrigation had three levels: 60%(W_1),70%(W_2) and 80%(W3) of the targeted relative water content at 0-40 cm of soil layer during jointing period of winter wheat.Nitrogen fertilization had three levels: not using nitrogen(N_0),using pure nitrogen of 195 kg/hm^2(N_(195)) and 255 kg/hm^2(N_(255)).Results showed that:(i)different supplemental irrigation and nitrogen fertilization significantly affected plant height and leaf area of winter wheat during key growth period.Under the same supplemental irrigation treatment,both plant height and leaf area of winter wheat showed as N_(255)> N_(195)> N_0(P <0.05).Plant height in N_(195) and N_(255)treatments was significantly higher than that in N_0 treatment,but there was not significant difference between N_(195) and N_(255)(P >0.05).Under the same nitrogen fertilization,plant height in W_2(569.4 m^3/hm^2) and W3(873.45 m^3/hm^2) treatments was significant higher than that in W_1(265.2 m^3/hm^2),but there was not significant difference between W_2 and W3(P >0.05).It illustrated that excessive nitrogen fertilization and supplemental irrigation did not significantly affect plant height and leaf area of winter wheat.(ii) Under the same nitrogen fertilization level,yield increase effect of winter wheat by supplemental irrigation showed a declining trend with nitrogen application amount increased.It illustrated that nitrogen fertilization and supplemental irrigation had certain critical values on the yield of winter wheat.When surpassing the critical value,the yield declined.When nitrogen fertilization amount was 195 kg/hm^2,and supplemental irrigation amount was 70% of field moisture capacity(569.4 m^3/hm^2),the highest yield 8500 kg/hm^2 could be obtained.(iii) During mature period of winter wheat,nitrogen accumulation amount of plant treated by nitrogen was significantly higher than that not treated by nitrogen(P <0.05).But under the treatments of W_2 and W3,nitrogen accumulation amount in N_(255) significantly declined when compared with N_(195)(P <0.05).Especially under W3(873.45 m^3/hm^2) level,nitrogen accumulation amount in N_(255) was even lower than N_0.Under the treatments of N_0 and N_(195),nitrogen accumulation amount of plant significantly increased with supplemental irrigation increased(P < 0.05).But under N_(255) treatment,there was not significant difference(P > 0.05).It illustrated that moderate supplemental irrigation and nitrogen fertilization could improve nitrogen absorption ability of winter wheat,but excessive supplemental irrigation and nitrogen fertilization were not favorable for plant's nitrogen absorption.(iv) Although the increase of supplemental irrigation during jointing period improved nitrogen absorption ability of winter wheat and promoted winter wheat absorbing more nitrogen,it inhibited nitrogen transferring and distributing to seed.Comprehensively considering growth condition of winter wheat and nitrogen risk condition,it is suggested that nitrogen application amount was 195 kg/hm^2,and supplemental irrigation reached 70% of field moisture capacity(569.4 m^3/hm^2),which could be as the suitable water and fertilizer use amounts in the region.

Moisture Absorption and Desorption in an Ionomer-Based Encapsulant:A Type of Self-Breathing Encapsulant for CIGS Thin-Film PV Modules

As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing to prevent moisture penetration is not required.The spontaneous moisture absorption and desorption of this encapsulant and its raw materials,poly(ethylene-co-acrylic acid)and an ionomer,are analyzed under different climatic conditions in this work.The relative air humidity is thermodynamically the driving force for these inverse processes and determines the corresponding equilibrium moisture content(EMC).Higher air humidity results in a larger EMC.The homogenization of the absorbed water molecules is a diffusion-controlled process,in which temperature plays a dominant role.Nevertheless,the diffusion coefficient at a higher temperature is still relatively low.Hence,under normal climatic conditions for the application of PV modules,we believe that the investigated ionomer-based encapsulant can“breathe”the humidity:During the day,when there is higher relative humidity,it“inhales”(absorbs)moisture and restrains it within the outer edge of the module;then at night,when there is a lower relative humidity,it“exhales”(desorbs)the moisture.In this way,the encapsulant protects the cell from moisture ingress.

Water Absorption Capcapability and Moisture Content Seasonal Changing of Salt-Crust in Lop Nur Dry Lake

The Lop Nur dry salt lake,Xinjiang province,is charactered by typical physiognomy salt-crust,located in39.6-41.3N.latitude and 89.6-91.4E.longitude.The thickness of salt-crust is about from 20 cm to 100 cm,and

An Anionic Polymer Incorporating Low Amounts of Hydrophobic Residues Is a Multifunctional Surfactant. Part 1: Emulsifying, Thickening,Moisture-Absorption and Moisture-Retention Abilities of a FattyAcid-Containing Anionic Polysaccharide

We have been studying the function and structure of fatty acid-containing extracellular polysaccharides (FACEPS) produced by bacteria belonging to the genus Rhodococcus. In this study, we examined the relationships between the structure and emulsifying, thickening, moisture-absorption, and moisture-retention capabilities of rhodococcal FACEPS using S-2 EPS produced by R. rhodochrous strain S-2. We prepared chemically deacylated S-2 EPS (DeAcyl S-2 EPS) and palmitoylated DeAcyl S-2 EPS (ReAcyl S-2 EPS), and compared them with native S-2 EPS. All of the properties were attenuated and recovered by deacylation and reacylation of S-2 EPS, respectively. These results suggest that the fatty acid moiety of rhodococcal FACEPS is involved in such functional properties. We also showed that palmitoylation improved the emulsifying, moisture-ab-sorption, and moisture-retention abilities of other acidic polysaccharides that are commercially available. These results suggest that the acidity of the polysaccharide backbone is at least partly responsible for the observed functionality of fatty acid-containing polysaccharides. To our knowledge, this is the first report on multifunctional property of an anionic polymer incorporating low amounts of hydrophobic residues. The present findings could be useful for the creation of new multifunctional surfactants from renewable raw materials for use in various industries, e.g., in cosmetics.

An Anionic Polymer Incorporating Low Amounts of Hydrophobic Residues Is a Multifunctional Surfactant. Part 2: Emulsification, Moisture Absorption, and Moisture Retention of Alkyl Esterified Poly-γ-Glutamic Acid

In the accompanying paper (Part 1), we showed that the fatty acid moiety and the acidity of the polysaccharide-backbone of a fatty acid-containing polysaccharide might be involved in its emul-sification, moisture absorption, and moisture retention abilities. In this study, we synthesized alkyl esterified poly-γ-glutamic acid (PGA) with various chain lengths and degrees of substitution of the alkyl moieties to examine how hydrophobic groups incorporated in the anionic polymer contribute to enhanced emulsification, moisture absorption, and moisture retention. With a low degree of alkylation of PGA, these abilities were drastically improved. To improve the moisture absorption of PGA, alkylation with a short chain length is effective in forming interspaces between PGA chains to trap water molecules. Hydrophobic-hydrophilic balance may also be important to improve the emulsification and moisture retention abilities of PGA alkylates. To the best of our knowledge, this is the first report of the relationship between the structure and the multifunctional abilities of an anionic polymer incorporated with a small amount of hydrophobic residue. PGA alkylates, as well as fatty acid-containing polysaccharides, have potential use as multifunctional surfactants throughout various industries.

Moisture Absorption and Diffusion of a Carbon Composite Structure

Composite materials are lightweight structures and have been wildly used in marine applications.A carbon composite structure usually absorbs moisture while in-service,which can significantly affect its properties,and detriments the overall performance.We perform a detailed study on moisture absorption and diffusion of a carbon fibre reinforced vinyl ester resin composite system.Composite samples are immersed directly in four different solutions at a temperature of 37±0.5℃for 1444h.The moisture diffusion is analysed through the Fickian diffusion model;the diffusion parameters are subsequently determined from the gravimetric data.The moisture absorption and interaction with the composite constituents are then discussed.These indicate the fundamentals of the moisture absorption and diffusion within the carbon composite structure.

Analysis of the Porosity Changing after Moisture Absorption in Functional Knitted Fabrics

The paper analyses the effect of stitch geometrical modality changing after moisture absorption on the porosity of knitted fabrics,and educes the formulas between porosity and stitch parameters.Regarding as the cell stitch,the increasing of yarn diameter brings the porosity decreasing and the fabric shrinking in the wale direction.While the diameter keeps invariability,the yarn elongating brings the fabric humping up as well as the increasing porosity.The air-permeability experiments have been conducted to validate the theoretical analysis,and there is reasonable agreement between the theories and experiments.

Moisture Absorption, Mass Loss and Evaporative Resistance of Clothing in Transient Condition

衣服整体的水蒸汽抵抗不是当通常作为干燥热屏蔽决定了。测量技术是更复杂的，测量价值在实验室之中不同。由于通过衣服整体的复杂潮湿转移过程，吸收并且蒸发的潮湿在取决于性质，衣服的厚度，和环境条件的短暂、稳定的州的阶段变化。这研究的 purpse 是在吸湿性的内衣内测量潮湿获得，并且恐水病、可渗透外部作为时间的功能穿，从“皮肤”以及从矮人调查集体损失，成为蒸气的热损失和总数从矮人加热损失确定，并且撕了决定 clothing.Manikin 的水蒸汽抵抗被穿湿“皮肤”模仿出汗的状况使用。在内部服装获得的潮湿内容对时间显示出一种指数的关系。在外部可渗透的层的潮湿显示出小获得。相反，集体损失直接指数地从湿皮肤减少。从矮人的集体损失在整个三个测试阶段是相对稳定的。成为蒸气的热损失关于从出汗的矮人的全部的热损失的 2/3。当与吸湿性的内部服装和可渗透的外部服装测量衣服整体的成为蒸气的抵抗时，对有透不过的外部层的措施整体不同，一小时测量时间是足够的得到相对稳定的结果。在第一小时和第三个小时之间的变化是不到 5% 。短暂时期和测量时间的长度依赖于渗透，衣服整体的厚度和环境条件。

Water Transport Models of Moisture Absorption and Sweat Discharge Yarns

An important property of moisture absorption and sweat discharge yarns is their water transport property. In the paper, two water transport models of moisture absorption and sweat discharge yarns were developed to investigate the influence factors on their wicking rate. In parallel Column Pores Model, wicking rate is determined by the equivalent capillary radius R and length of the capillary tube L. In Pellets Accumulation Model, wicking rate is decided by the capillary radius r and length of the fiber unit assemble L0.

Water Absorption Capacity and Coating Adhesion on Thermally Modified and Not-Modified Spruce Wood(Blue Stained or Free of Blue Stained)

This study aimed to investigate the water absorption capacity of thermally modified and non-modified spruce and blue-stained spruce wood.The wettability of wood depends on various factors,including its type,density,porosity,and surface treatment.Wood can swell and become distorted when exposed to water or humidity,impacting its structural integrity.Hence,it is crucial to consider the water and water vapour uptake in the wood when choosing materials for applications that are likely to be exposed to moisture.Various moisture absorption tests were conducted to assess water absorption capacity,including short-term and long-term water absorption and water vapour absorption.The results showed a significant difference in the long-term exposure to water,which was related to the density of the wood.The study examined the influence of thermal treatment on the physical properties of wood and observed significant variations in mass change due to coating,indicating differences in adhesion among different wood types.Vacuum-treated blue-stained Norway spruce demonstrated higher adhesion(5%–15%)compared to air-treated samples.Furthermore,cohesion tests revealed lower cohesion force in blue-stained Norway spruce(approximately 20%–30%)compared to Norway spruce.The study also used industry-standard tests to investigate the adhesion and cohesion of nano-coatings on wood surfaces.The results provided valuable information on the properties of coatings applied to wood,which is vital in protecting and decorating wood while also providing preventive protection against wood pests,weathering,and mechanical influences.Wood modification in vacuum involves subjecting the wood to a low-pressure environment to remove air and moisture,allowing for deeper and more uniform penetration of treatment chemicals.In contrast,wood modification in air relies on the natural circulation of air to facilitate the absorption of chemical treatments,without the need for a vacuum chamber.

湿热处理对红薯淀粉特性的影响

为了研究湿热处理对红薯淀粉理化和结构等特性的影响,以五种红薯淀粉为实验对象,测定并分析湿热处理后淀粉溶解度、膨润力、持水力、透光率、凝沉性等理化特性的变化情况,进而探明湿热处理对不同初始含水量红薯淀粉吸水特性及晶体结构的影响规律。结果表明,经湿热处理后红薯淀粉的溶解度、膨润力、凝沉性与透光率均较原淀粉降低,持水力均增强,且五种红薯淀粉均呈现相同趋势,说明红薯品种与湿热处理对淀粉性质的影响规律无显著相关性。经湿热处理后红薯淀粉未见新的衍射特征峰,晶体类型仍为C型,而衍射强度和结晶度降低。湿热处理淀粉吸水达到平衡所需要时间较原淀粉短,且饱和吸水量较原淀粉有减小的趋势。利用Peleg模型方程模拟湿热处理后红薯淀粉的吸水规律,并计算出浸泡动力学吸水常数K1和K2,确定了淀粉的吸水动力学方程,可预测湿热处理后红薯淀粉在浸泡过程中的水分含量。

基于疏水仿生学提升超细高氯酸铵热分解、安全及防吸湿性能的研究

为了研制出兼具高燃速和高安全性能的固体推进剂,以改善高氯酸铵的性能为目标,采用液相沉积法制备了具有核壳结构的超细高氯酸铵@硬脂酸锌(UF-AP@ZnSA)复合物;使用扫描电镜(SEM)、热重-差示扫描量热法(TG-DSC)、傅里叶变换红外光谱(FT-IR)等对样品的形貌、结构和热分解性能进行了表征;并测量了样品的撞击感度、摩擦感度、吸湿率和接触角等参数;采用热分析-红外联用技术分析并解释了硬脂酸锌(ZnSA)催化UF-AP的热分解机理。结果表明,UF-AP表面生成了ZnSA壳层;不同壳层含量的复合物中UF-AP高温分解峰从424.3℃降至370~385℃,相较于原料UF-AP,放热区间更加集中,放热量更大;UF-AP@ZnSA复合物特性落高(H_(50))相较于原料增加了27.6 cm,摩擦感度的爆炸概率减小了76%,安全性能大幅度提升;壳层质量分数为5%的UF-AP@ZnSA复合物72 h的吸湿率为0.05%,较原料UF-AP的吸湿率降低约90%,防吸湿性能得到明显提升。

内抹调湿砂浆外墙吸放湿特性及对负荷影响分析

本文从建筑围护结构节能出发,以内抹WSE(木质纤维Wood fibre、海泡石Sepio⁃lite、膨胀珍珠岩Expanded perlite)基复合调湿保温砂浆外墙为研究对象,将其与内抹普通砂浆外墙对比,分析吸放湿特性及其对负荷的影响.研究使用COMSOL Multiphysics有限元软件的建筑材料热湿耦合模型,分析环境湿度变化与外墙之间的湿迁移变化,以及与外墙的传热传质.以夏热冬冷典型气候地区长沙为例,分析内抹WSE基复合调湿保温砂浆外墙的负荷及潜热负荷占比,同时选取夏热冬暖地区广州和寒冷地区北京对比分析外墙的全年能耗.研究发现,内抹WSE基复合调湿保温砂浆外墙的吸放湿速率远大于内抹普通砂浆的外墙,并能长时间保持高速的吸放湿状态,同时比内抹普通砂浆墙体节省22.31%~23.85%的全年负荷.墙体在吸湿过程中,温升与吸湿速率能力体现出一致性,表明墙体内表面湿迁移对温度有着重要影响,并且湿迁移越大对温度影响越大.墙体在放湿过程中,温度迅速下降是放湿速率快的表现.内抹WSE基复合调湿保温砂浆墙体具有优良的吸放湿特性和节能潜力,可用于建筑围护结构节能.

棉和羽毛蛋白丝交织物的性能测试

对棉和羽毛蛋白丝交织物进行吸湿速干、透湿、抗静电和防紫外线性能测试,并与棉织物和棉涤纶丝织物进行对比分析,得出结论:棉羽毛蛋白丝织物的吸水率、滴水扩散时间、芯吸高度达到GB/T 21655.1—2023中吸湿速干织物Ⅱ级的要求,但干燥速率未达到吸湿速干织物要求:棉羽毛蛋白丝织物透湿性能较好,抗静电性能优异,符合防紫外线产品要求;棉羽毛蛋白丝织物适宜用作夏季服装面料。

基于响应面-主成分分析法优化再造烟叶表面改性膜材料的配方研究

【背景和目的】针对加热卷烟用再造烟叶吸湿性过强的问题,克服其在制丝、卷包以及贮存过程中易吸潮的缺陷,确保其耐加工性以及感官质量的稳定性。【方法】以壳聚糖、石蜡、黄原胶为配方组分,在单因素实验的基础上,采用响应面-主成分分析法优化膜材料配方,开发出具有适中疏水性的膜材料涂布液,用于再造烟叶表面疏水改性。【结果】优化得到膜材料配方为:壳聚糖、石蜡和黄原胶的涂布量分别为0.6 g/m^(2)、1.5 g/m^(2)、1.6 g/m^(2),在此条件下制得改性再造烟叶的接触角87.542°、吸湿率10.98%、放湿率2.16%、感官质量得分87分。相比于传统再造烟叶,改性后再造烟叶的吸湿率和放湿率均显著降低,感官质量基本保持,抗张强度有所提升,再造烟叶的综合性能得到明显改善。

二甲基对苯二甲基型氰酸酯的合成与性能研究

以对苯二甲基二甲醚为原料合成了二甲基对苯二甲基型苯酚(DMPXPh)。采用氯化氰-酚方法制备出新型二甲基对苯二甲基型氰酸酯(DMPXCy),并测定了其结构。考察了材料的热性能、耐湿热性、介电性能和力学性能,并与双酚A型氰酸酯(BADCy)进行比较。研究结果表明:(1)红外和核磁氢谱表征证明已经成功地制备出目标酚中间体,并且酚中间体已被氰酸酯化制备成氰酸酯单体。(2)DMPXCy的固化行为和热性能研究表明,DMPXCy反应活性低于BADCy树脂,并且加入有机金属催化剂后,固化温度明显降低,可在280℃内阶梯固化。另外,DMPXCy树脂的玻璃化转变温度比BADCy树脂低,热稳定性基本相同,但DMPXCy的残炭率较高,显示出一定的耐烧蚀性。(3)力学性能研究表明,DMPXCy树脂总体力学强度与BADCy相近,拉伸强度略低。(4)DMPXCy树脂吸湿性和介电性能研究说明,DMPXCy树脂展现出优异的介电性能和低吸湿性,介电常数(ε)与介电损耗角正切(tanδ)分别为2.650和0.00450,饱和吸湿率为0.70%,远低于BADCy树脂的介电损耗和吸湿率。DMPXCy树脂作为低介电透波材料或高尺寸精度航天复合材料和胶粘剂的树脂基体,具有良好的应用潜力。

大别山艾叶多糖提取工艺优化及其吸湿保湿、抗氧化性能研究

为了挖掘大别山艾草的应用潜力,开发出更多艾草相关产品,促进大别山革命老区经济社会发展。采用正交试验优化超声波-酶法提取大别山艾叶多糖工艺,并对艾叶多糖的吸湿保湿和抗氧化性能进行测定。试验结果表明,大别山艾叶多糖的最佳提取工艺为料液比1∶35(g/mL)、纤维素酶添加量1%、超声时间25 min,在该条件下,艾叶多糖提取率为1.72%。在相对湿度为43%的环境下,大别山艾叶多糖的吸湿率为35.7%;在相对湿度为81%的环境下,吸湿率为40.3%;在干燥环境下,保湿率为66.9%。大别山艾叶多糖对DPPH自由基和羟基自由基都有清除作用,在浓度为1.2 mg/mL对DPPH自由基的清除率为28.5%,对羟基自由基的清除率为30.4%。大别山艾叶多糖具有良好的吸湿和保湿性能,并且具有一定的抗氧化活性,可以开发其作为一种天然的食品添加剂。

长期贮藏干枣在不同温度下的吸水和加工特性

干枣(Ziziphus jujuba Mill.)是药食兼用的食品原料,其保健功能、贮藏和加工特性备受关注。长期贮藏的干枣脱水严重,果肉变硬、果皮发暗,商品价值降低。该文以分别贮藏约1和13个月的新疆骏枣和灰枣干枣为对象,研究干枣的浸泡吸(复)水的规律及其对干枣加工性能的影响。结果发现,贮藏13个月的骏枣和灰枣的湿基含水量较贮藏1个月的骏枣和灰枣减少了约50%,贮藏时间对果形指数、果肉质地和成分均有一定影响,长期贮藏的干枣仍具有很好的加工利用价值。干枣的吸水曲线大都呈对数曲线的规律,吸水过程受水温和干枣种类影响。低场核磁共振成像(Low-field Magnetic Resonance Imaging,LF-MRI)分析显示,水分主要从枣蒂和表面渗入到枣果内。贮藏约13个月的骏枣和灰枣的干基含水量分别为43.18 g/100 g(T=40℃)和41.06 g/100 g(T=60℃)时,出现轻微软化现象,此时可进行去核和切片加工;当干枣浸泡至干基含水量为129 g/100 g时,果肉软化充分,水分分布均匀,则可进行打浆加工,浆液粒度和色泽均较好。

单向CF/PA6复合材料性能劣化及老化寿命预测

利用热压成型工艺制备出碳纤维(CF)/尼龙6(PA6)复合材料单向板,并将复合材料试样置于蒸馏水热水浴中,分别在25,60,80℃下进行不同时间的湿热老化,再对湿热老化后复合材料试样进行吸湿测试、三点弯曲测试、微观形貌表征,探究复合材料的吸湿规律、力学性能劣化规律和微观形貌变化,并对复合材料的长期寿命进行预测。结果发现,复合材料在25,60℃下的吸湿行为基本符合Fick扩散定律,而80℃下在老化最后阶段出现了背离Fick扩散定律现象。复合材料的弯曲强度随老化温度、老化时间的增加呈下降趋势,分别在25,60,80℃下老化120 d后,试样弯曲强度分别下降了22.78%,25.0%,26.25%。但是老化温度、老化时间对弯曲弹性模量无显著影响,且CF与PA6树脂之间的界面黏合性能随着温度、时间的增加逐渐变差。以绍兴2021年平均温度作为服役温度,基于加速老化测试模型和阿伦尼乌斯理论建立了CF/PA6复合材料在服役环境下剩余弯曲强度的预测模型,可预测到1 400 d后,CF/PA6复合材料的弯曲强度保留率在64.8%左右。

抗菌热湿舒适复合功能服用面料的性能

为开发热湿条件下穿着健康舒适的抗菌服用面料,以桑蚕丝为经纱,蜂窝抗菌涤纶纤维、天丝、蜂窝抗紫外涤纶纤维、蜂窝玉石涤纶纤维等混纺为纬纱,通过改变纬纱种类、织物组织及纬密等设计并试织了A、B两个系列共16种织物;并对其吸湿速干、抗菌与热传递性能等进行测试,运用模糊综合分析法对其抗菌性能、热湿舒适性进行评价。结果表明:当纬纱中含有天丝成分时织物吸湿速干性能更佳,随着织物组织浮长变短、纬密增大,其吸湿速干性能整体呈下降趋势;织物具有优良的抗菌性,纬纱中蜂窝抗菌涤纶纤维含量越高,织物抗菌性能越好。织物热阻随着纬纱中天丝含量增加而减小,当含有蜂窝玉石涤纶纤维时织物热传递性能最佳;组织浮长更短的织物热传递性能更优。模糊综合分析结果表明,A系列中以天丝蜂窝抗菌涤纶纤维蜂窝抗紫外涤纶纤维(306010)为纬纱并以16枚加强纬缎织造的织物抗菌热湿舒适性能最佳,B系列中纬密为46根cm时织物抗菌热湿舒适性能最佳。