Hydrogels inevitably undergo dehydration,structural collapse,and shrinkage deformation due to the uninterrupted evaporation in the atmosphere,thereby losing their flexibility,slipperiness,and manufacturing precision.H...Hydrogels inevitably undergo dehydration,structural collapse,and shrinkage deformation due to the uninterrupted evaporation in the atmosphere,thereby losing their flexibility,slipperiness,and manufacturing precision.Here,we propose a novel bioinspired strategy to construct a spontaneously formed‘skin’on the slippery hydrogels by incorporating biological stress metabolites trehalose into the hydrogel network,which can generate robust hydrogen bonding interactions to restrain water evaporation.The contents of trehalose in hydrogel matrix can also regulate the desiccation-tolerance,mechanical properties,and lubricating performance of slippery hydrogels in a wide range.Combining vat photopolymerization three-dimensional printing and trehalose-modified slippery hydrogels enables to achieve the structural hydrogels with high resolution,shape fidelity,and sophisticated architectures,instead of structural collapse and shrinkage deformation caused by dehydration.And thus,this proposed functional hydrogel adapts to manufacture large-scale hydrogels with sophisticated architectures in a long-term process.As a proof-of-concept demonstration,a high-precision and sophisticated slippery hydrogel vascular phantom was easily fabricated to imitate guidewire intervention.Additionally,the proposed protocol is universally applicable to diverse types of hydrogel systems.This strategy opens up a versatile methodology to fabricate dry-resistant slippery hydrogel for functional structures and devices,expanding their high-precision processing and broad applications in the atmosphere.展开更多
Electroosmosis has been shown to be an effective means of different applications in various fields such as Micro-Electro-Mechanical systems (MEMS) and biomimetics applications. This paper aims to prove the concept t...Electroosmosis has been shown to be an effective means of different applications in various fields such as Micro-Electro-Mechanical systems (MEMS) and biomimetics applications. This paper aims to prove the concept that the electroosmosis phenomena can also be cooperated into larger scale applications in the building service industry like dehumidification or damping proof. The electroosmotic flow inside a porous medium is validated experimentally to further understand the dehumidification mechanism of combined techniques. An experimental test validates that the condensation from the porous medium can be obtained by electroosmotic force generated by external electric field, especially for specific desiccant powders like zeolite and diatomaceous earth. With a range of volts from 5 V to 20 V applying between the testing plates, the maximum flow rate through the cross section in the testing plate achieved during the peak period is 1.35 laL'min 1. These promising phenomena can act as an alternative way for energy choice in dehumidification industrial field. Further researches on new regeneration methods for solid desiccant dehumidification are required to make the system simple, energy-saving and suitable for small air conditioning units.展开更多
Suitable control of the humidity can contribute to electric energy savings. However, the present dehumidification system has many weak points. The liquid desiccant air-conditioning system has recently gained growing i...Suitable control of the humidity can contribute to electric energy savings. However, the present dehumidification system has many weak points. The liquid desiccant air-conditioning system has recently gained growing interest from the stand point of reducing energy consumption during dehumidification. In order to find the appropriate ionic liquids(ILs) as a desiccant for the liquid desiccant air-conditioner system, we conducted a systematic evaluation of the humidification capability of 16 types of ILs. Among the tested ILs, tributyl(methyl)phosphonium dimethyl phosphate([P4441][DMPO_4]) exhibited the best dehumidification capacity and had a less corrosive effect on four types of metals as possible piping materials. It should be noted that this [P_(4441)][DMPO_4] has a very stable nature and produced no odor while conducting the experiment and storing for over 1 year at room temperature under ambient conditions. Furthermore, it was revealed that a 77%(w/w) aqueous solution of [P4441][DMPO_4] worked as an efficient desiccant liquid for the liquid desiccant air-conditioner system.展开更多
The performance of liquid desiccant dehumidification systems can be improved substantially by applying the ultrasonic atomization technology.However,considering the currently-high expense and extra power for the ultra...The performance of liquid desiccant dehumidification systems can be improved substantially by applying the ultrasonic atomization technology.However,considering the currently-high expense and extra power for the ultrasonic atomizers,it’s unclear if the ultzasonic atomization dehumidifying system(UADS)possesses good economic performance over the conventional packed-bed(PBD)systems.This paper conducted a comparative study on the economic performance between the UADS and PBD.An economic analysis model integrated with the empirical formulae was established while an office building located in Guangzhou,China was employed as the study case.The results indicate the UADS may fit best for buildings with deep-dehumidification needs but smaller-scale areas.展开更多
The aim of this research was to study and design a solid desiccant dehumidification system suitable for tropical climate to reduce the latent load of air-conditioning system and improve the thermal comfort. Different ...The aim of this research was to study and design a solid desiccant dehumidification system suitable for tropical climate to reduce the latent load of air-conditioning system and improve the thermal comfort. Different dehumidifiers such as desiccant column and desiccant wheel were investigated. The ANSYS and TRASYS software were used to predict the results of dehumidifiers and the desiccant cooling systems, respectively. The desiccant bed contained approximately 15 kg of silica-gel, with 3 mm average diameter. Results indicated that the pressure drop and the adsorption rate of desiccant column are usually higher than those of the desiccant wheel. The feasible and practical adsorption rate of desiccant wheel was 0.102 kgw/h at air flow rate 1.0 kg/min, regenerated air temperature of 55?C and at a wheel speed of 2.5 rpm. The humidity ratio of conditioning space and cooling load of split-type air conditioner was decreased to 0.002 kgw/kgda (14%) and 0.71 kWth (19.26%), respectively. Consequently, the thermal comfort was improved from 0.5 PMV (10.12% PPD) to 0.3 PMV (7.04% PPD).展开更多
A new solar coupling regeneration system is proposed in order to improve the reliability of solar desiccant regeneration system.The new system makes comprehensively use of the solar energy and can also be appropriate ...A new solar coupling regeneration system is proposed in order to improve the reliability of solar desiccant regeneration system.The new system makes comprehensively use of the solar energy and can also be appropriate for energy-storage in a night operation mode when the electric power supply is at its valley.Comparison of the performance of the new system,the solar thermal regeneration system and the solar electrodialysis regeneration system are made and the influential factors of the performance of the new system are investigated.The results reveal that the new system will be more energy efficient than the solar thermal regeneration system and the solar electrodialysis regeneration system.展开更多
The high temperature heat pump and desiccant wheel(HTHP&DW) system can make full use of heat released from the condenser of heat pump for DW regeneration without additional heat. In this study, DW operation in the...The high temperature heat pump and desiccant wheel(HTHP&DW) system can make full use of heat released from the condenser of heat pump for DW regeneration without additional heat. In this study, DW operation in the HTHP&DW system was investigated experimentally, and the optimization analysis of HTHP&DW system was carried out. The performance of DW had influence on the dehumidification(evaluated by dehumidification and regeneration effectiveness) and cooling load(evaluated by thermal and adiabatic effectiveness). The results show that the enthalpy increase occurred in all the experiments. Compared to the isosteric heat, heat accumulation in the desiccant and matrix material and heat leakage from regeneration side to process side have greater influence on the adiabatic effectiveness. Higher regeneration temperature leads to lower adiabatic effectiveness that increases more cooling load of the system. When the regeneration temperature is 63℃, the maximal dehumidification effectiveness is 35.4% and the satisfied adiabatic effectiveness is 88%, which contributes to the optimal balance between dehumidification and cooling.展开更多
In the present study, dynamic performance of single bed desiccant regeneration system has been investigated experimentally. The desiccant bed operates as an adsorber and then as a regenerator, intermittently. In the e...In the present study, dynamic performance of single bed desiccant regeneration system has been investigated experimentally. The desiccant bed operates as an adsorber and then as a regenerator, intermittently. In the experimental work of this investigation, Silica gel is used as a desiccant material. In the regeneration process, hot air from an air heater is blown through the bed using an air blower. The performance of desorption process at different conditions of flowing air is demonstrated. The experimental tests were carried out at different conditions of inlet air and initial bed parameters. Temperature and humidity of air at inlet and exit of the bed were measured. The obtained results showed that hot air with an inlet temperature ranging from 40°C to 75°C could release a notable amount of water from the desiccant bed. The relation between the studied parameters during the desorption processes is correlated. Results also show that the “Rehabilitation period” in desorption process should be eliminated to decrease the desorption time and it could be eliminated if the hot air mass flow rate is greater than 1.92 kg/hr per kg of silica gel.展开更多
Optimization of the open absorption desiccant cooling system has been carried out in the present work. A finite difference method is used to simulate the combined heat and mass transfer processes that occur in the liq...Optimization of the open absorption desiccant cooling system has been carried out in the present work. A finite difference method is used to simulate the combined heat and mass transfer processes that occur in the liquid desiccant regenerator which uses calcium chloride (CaCl2) solution as the working desiccant. The source of input heat is assumed to be the total radiation incident on a tilted surface. The system of equations is solved using the Matlab-Simulink platform. The effect of the important parameters, namely the regenerator length, desiccant solution flow rate and concentration, and air flow rates, on the performance of the system is investigated. In order to optimize the system performance, a genetic algorithm technique has been applied. The system coefficient of performance COP has been maximized for different design parameters. It has been found that the maximum values of COP could be obtained for different combinations of regenerator length solution flow rate and air flow rate. Therefore, it is essential to select the design parameters for each ambient condition to maximize the performance of the system.展开更多
This paper reviews the principle and application of the thermally activated desiccant cooling systems with their capability to perform efficiently in hot-humid climates.The paper first introduces the continuous increa...This paper reviews the principle and application of the thermally activated desiccant cooling systems with their capability to perform efficiently in hot-humid climates.The paper first introduces the continuous increase of thermal comfort required in building and their relation with the consumption of conventional energy sources.The importance of desiccant cooling technology and its applications has been introduced as well.The energy and environmental issues with the conventional energy supply and the demand with the environmental problems and conditions mainly related to indoor air quality have been also discussed in the second chapter of this paper.The third part of this paper deals with different techniques and systems applied for cooling and dehumidification including the principles of solid and liquid desiccant applications.Indeed,these systems perform well in hothumid climates.The result of a case study of the solid desiccant cooling system combined with solar energy for the desiccant wheel regeneration has been presented in the last chapter in this paper to show the capability of these systems once well applied in a hot-humid climate.展开更多
During low tide,the intertidal seagrass Enhalus acoroides is often exposed to high light and desiccation,which can seriously threaten its survival,at least partly by inhibiting photosystem Ⅱ(PSⅡ)activity.The respons...During low tide,the intertidal seagrass Enhalus acoroides is often exposed to high light and desiccation,which can seriously threaten its survival,at least partly by inhibiting photosystem Ⅱ(PSⅡ)activity.The response of leaves of E.acoroides to high light and desiccation was compared for seedlings and mature plants.Results show that the resistance of seedling and mature leaves to high light was quite similar,but to desiccation was very different.Seedling leaves were more sensitive to desiccation than the mature plant leaves,but had better water retention.The damage of desiccation to seedling leaves was mainly caused by dehydration,whereas that to mature plant leaves was caused by hypersaline toxicity.The recovery rate of PSⅡ of seedling leaves was significantly slower than that of the mature plants after the stresses disappeared,which may at least partly contribute to seedling mortality in the wild.In addition,compared to high light,desiccation seriously inhibited the recovery rate of PSⅡ activities even if the leaves became fully rehydrated to their normal relative water content(RWC)in the following re-immersion.Desiccation inhibited the recovery rate of RC/CS_(M)(reaction center per cross section(at t=t_(Fm)))to decrease the production of assimilatory power,which maybe the cause of the slower PSⅡ recovery in desiccation treatments.This study demonstrates that desiccation particularly coupling with high light have a very negative ef fect on the PSⅡ of E.acoroides during low tide and the sensitivity of seedlings and mature plants to desiccation is significantly different,which have important reference significance to choose an appropriate transplanting depth where seedlings and mature plants of E.acoroides not only receive sufficient light for growth,but also that minimize desiccation stress during low tide.展开更多
The pre-harvest application of herbicides may impair seed quality. This way, this paper was conducted to evaluate the effects of the application of desiccant herbicides on the physiological quality of pigeonpea seeds....The pre-harvest application of herbicides may impair seed quality. This way, this paper was conducted to evaluate the effects of the application of desiccant herbicides on the physiological quality of pigeonpea seeds. Six batches of seeds from plants desiccated with glyphosate were evaluated at doses: 1.125 (B1), 1.5 (B2) and 1.875 L·ha-1 (B3);and Gramocil (20% Paraquat + 10% Diurom) at doses: 1.5 (B4) and 2 L·ha-1 (B5), and a control which received no application (B6). Seed viability was assessed through the germination standard test, and vigor through the first germination count, accelerated aging, electrical conductivity, seedling length, seedling dry matter and biomass density tests. The experimental design was the completely randomized, with four replications. Data were submitted to variance analysis, and when significant effects were observed, the Scott- Knott test was carried out at 5% probability using the SISVAR 5.1 software. The results showed that: a) the application of 1.875 L·ha-1 of glyphosate was harmful to pigeonpea seed viability and vigor, evaluated through the accelerated aging test;b) applications of glyphosate in a 1.875 L·ha-1 dose and Gramocil in 2 L·ha-1 resulted in low vigor according to the electrical conductivity test of seeds;and c) the seed vigor measured by the first count, seedling length, seedling dry matter and biomass density test was not influenced by the type of desiccant applied.展开更多
Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affi...Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affiliated product will win the attention of parents.Against the background of consumption upgrading,consumers have had higher requirements on the humanization and safety design of products.Most of milk powder spoons on the market are plastic,and the disposal of waste milk powder spoon has gradually become a burden for the environment.Based on the environment-friendly and developmental concept,and also the characteristics of infant development,this paper proposed the“in-one”design,applied color and tactile designs into the milk powder design,chose food grade silicone to make the milk powder spoon not only a spoon but also a baby teether toy,so as to expand the service life and functions of the product,meet the requirements of saving energy,protecting environment and developing circular economy,which also to some extent reduces the burden on environment brought by plastics,improves the efficiency of junk recycling,and meet the individualized needs of consumers.展开更多
基金the financial support from the National Key Research and Development Program of China(2022YFB4600101)the National Natural Science Foundation of China(52175201,52005484,and 52205228)+6 种基金the Research Program of Science and Technology Department of Gansu Province(21YF5FA139 and 22JR5RA107)the Shandong Provincial Natural Science Foundation(ZR2023OE090)the Major Program(ZYFZFX-2)the Cooperation Foundation for Young Scholars(HZJJ23-02)of the Lanzhou Institute of Chemical Physics,CASthe Western Light Project,CAS(xbzg-zdsys-202007)the Taishan Scholars Programthe Oasis Scholar of Shihezi University。
文摘Hydrogels inevitably undergo dehydration,structural collapse,and shrinkage deformation due to the uninterrupted evaporation in the atmosphere,thereby losing their flexibility,slipperiness,and manufacturing precision.Here,we propose a novel bioinspired strategy to construct a spontaneously formed‘skin’on the slippery hydrogels by incorporating biological stress metabolites trehalose into the hydrogel network,which can generate robust hydrogen bonding interactions to restrain water evaporation.The contents of trehalose in hydrogel matrix can also regulate the desiccation-tolerance,mechanical properties,and lubricating performance of slippery hydrogels in a wide range.Combining vat photopolymerization three-dimensional printing and trehalose-modified slippery hydrogels enables to achieve the structural hydrogels with high resolution,shape fidelity,and sophisticated architectures,instead of structural collapse and shrinkage deformation caused by dehydration.And thus,this proposed functional hydrogel adapts to manufacture large-scale hydrogels with sophisticated architectures in a long-term process.As a proof-of-concept demonstration,a high-precision and sophisticated slippery hydrogel vascular phantom was easily fabricated to imitate guidewire intervention.Additionally,the proposed protocol is universally applicable to diverse types of hydrogel systems.This strategy opens up a versatile methodology to fabricate dry-resistant slippery hydrogel for functional structures and devices,expanding their high-precision processing and broad applications in the atmosphere.
文摘Electroosmosis has been shown to be an effective means of different applications in various fields such as Micro-Electro-Mechanical systems (MEMS) and biomimetics applications. This paper aims to prove the concept that the electroosmosis phenomena can also be cooperated into larger scale applications in the building service industry like dehumidification or damping proof. The electroosmotic flow inside a porous medium is validated experimentally to further understand the dehumidification mechanism of combined techniques. An experimental test validates that the condensation from the porous medium can be obtained by electroosmotic force generated by external electric field, especially for specific desiccant powders like zeolite and diatomaceous earth. With a range of volts from 5 V to 20 V applying between the testing plates, the maximum flow rate through the cross section in the testing plate achieved during the peak period is 1.35 laL'min 1. These promising phenomena can act as an alternative way for energy choice in dehumidification industrial field. Further researches on new regeneration methods for solid desiccant dehumidification are required to make the system simple, energy-saving and suitable for small air conditioning units.
基金supported by a fund for environmental research from Tottori University
文摘Suitable control of the humidity can contribute to electric energy savings. However, the present dehumidification system has many weak points. The liquid desiccant air-conditioning system has recently gained growing interest from the stand point of reducing energy consumption during dehumidification. In order to find the appropriate ionic liquids(ILs) as a desiccant for the liquid desiccant air-conditioner system, we conducted a systematic evaluation of the humidification capability of 16 types of ILs. Among the tested ILs, tributyl(methyl)phosphonium dimethyl phosphate([P4441][DMPO_4]) exhibited the best dehumidification capacity and had a less corrosive effect on four types of metals as possible piping materials. It should be noted that this [P_(4441)][DMPO_4] has a very stable nature and produced no odor while conducting the experiment and storing for over 1 year at room temperature under ambient conditions. Furthermore, it was revealed that a 77%(w/w) aqueous solution of [P4441][DMPO_4] worked as an efficient desiccant liquid for the liquid desiccant air-conditioner system.
基金Fundamental Research Funds for the Central Universities of China(No.2232018D3-36)Shanghai Sailing Program,China(No.19YF1401800)China Postdoctoral Science Foundation(No.2018M630385)
文摘The performance of liquid desiccant dehumidification systems can be improved substantially by applying the ultrasonic atomization technology.However,considering the currently-high expense and extra power for the ultrasonic atomizers,it’s unclear if the ultzasonic atomization dehumidifying system(UADS)possesses good economic performance over the conventional packed-bed(PBD)systems.This paper conducted a comparative study on the economic performance between the UADS and PBD.An economic analysis model integrated with the empirical formulae was established while an office building located in Guangzhou,China was employed as the study case.The results indicate the UADS may fit best for buildings with deep-dehumidification needs but smaller-scale areas.
文摘The aim of this research was to study and design a solid desiccant dehumidification system suitable for tropical climate to reduce the latent load of air-conditioning system and improve the thermal comfort. Different dehumidifiers such as desiccant column and desiccant wheel were investigated. The ANSYS and TRASYS software were used to predict the results of dehumidifiers and the desiccant cooling systems, respectively. The desiccant bed contained approximately 15 kg of silica-gel, with 3 mm average diameter. Results indicated that the pressure drop and the adsorption rate of desiccant column are usually higher than those of the desiccant wheel. The feasible and practical adsorption rate of desiccant wheel was 0.102 kgw/h at air flow rate 1.0 kg/min, regenerated air temperature of 55?C and at a wheel speed of 2.5 rpm. The humidity ratio of conditioning space and cooling load of split-type air conditioner was decreased to 0.002 kgw/kgda (14%) and 0.71 kWth (19.26%), respectively. Consequently, the thermal comfort was improved from 0.5 PMV (10.12% PPD) to 0.3 PMV (7.04% PPD).
基金Project(51036001)supported by the National Natural Science Foundation of ChinaProject(2011BAJ03B05)supported by the National Science and Technology Pillar Program during the 12th Five-Year Plan Period of China
文摘A new solar coupling regeneration system is proposed in order to improve the reliability of solar desiccant regeneration system.The new system makes comprehensively use of the solar energy and can also be appropriate for energy-storage in a night operation mode when the electric power supply is at its valley.Comparison of the performance of the new system,the solar thermal regeneration system and the solar electrodialysis regeneration system are made and the influential factors of the performance of the new system are investigated.The results reveal that the new system will be more energy efficient than the solar thermal regeneration system and the solar electrodialysis regeneration system.
基金Supported by the Danish International DSF Project(No.09-71598)Chinese International Collaboration Project(No.2010DFA62410)
文摘The high temperature heat pump and desiccant wheel(HTHP&DW) system can make full use of heat released from the condenser of heat pump for DW regeneration without additional heat. In this study, DW operation in the HTHP&DW system was investigated experimentally, and the optimization analysis of HTHP&DW system was carried out. The performance of DW had influence on the dehumidification(evaluated by dehumidification and regeneration effectiveness) and cooling load(evaluated by thermal and adiabatic effectiveness). The results show that the enthalpy increase occurred in all the experiments. Compared to the isosteric heat, heat accumulation in the desiccant and matrix material and heat leakage from regeneration side to process side have greater influence on the adiabatic effectiveness. Higher regeneration temperature leads to lower adiabatic effectiveness that increases more cooling load of the system. When the regeneration temperature is 63℃, the maximal dehumidification effectiveness is 35.4% and the satisfied adiabatic effectiveness is 88%, which contributes to the optimal balance between dehumidification and cooling.
文摘In the present study, dynamic performance of single bed desiccant regeneration system has been investigated experimentally. The desiccant bed operates as an adsorber and then as a regenerator, intermittently. In the experimental work of this investigation, Silica gel is used as a desiccant material. In the regeneration process, hot air from an air heater is blown through the bed using an air blower. The performance of desorption process at different conditions of flowing air is demonstrated. The experimental tests were carried out at different conditions of inlet air and initial bed parameters. Temperature and humidity of air at inlet and exit of the bed were measured. The obtained results showed that hot air with an inlet temperature ranging from 40°C to 75°C could release a notable amount of water from the desiccant bed. The relation between the studied parameters during the desorption processes is correlated. Results also show that the “Rehabilitation period” in desorption process should be eliminated to decrease the desorption time and it could be eliminated if the hot air mass flow rate is greater than 1.92 kg/hr per kg of silica gel.
文摘Optimization of the open absorption desiccant cooling system has been carried out in the present work. A finite difference method is used to simulate the combined heat and mass transfer processes that occur in the liquid desiccant regenerator which uses calcium chloride (CaCl2) solution as the working desiccant. The source of input heat is assumed to be the total radiation incident on a tilted surface. The system of equations is solved using the Matlab-Simulink platform. The effect of the important parameters, namely the regenerator length, desiccant solution flow rate and concentration, and air flow rates, on the performance of the system is investigated. In order to optimize the system performance, a genetic algorithm technique has been applied. The system coefficient of performance COP has been maximized for different design parameters. It has been found that the maximum values of COP could be obtained for different combinations of regenerator length solution flow rate and air flow rate. Therefore, it is essential to select the design parameters for each ambient condition to maximize the performance of the system.
文摘This paper reviews the principle and application of the thermally activated desiccant cooling systems with their capability to perform efficiently in hot-humid climates.The paper first introduces the continuous increase of thermal comfort required in building and their relation with the consumption of conventional energy sources.The importance of desiccant cooling technology and its applications has been introduced as well.The energy and environmental issues with the conventional energy supply and the demand with the environmental problems and conditions mainly related to indoor air quality have been also discussed in the second chapter of this paper.The third part of this paper deals with different techniques and systems applied for cooling and dehumidification including the principles of solid and liquid desiccant applications.Indeed,these systems perform well in hothumid climates.The result of a case study of the solid desiccant cooling system combined with solar energy for the desiccant wheel regeneration has been presented in the last chapter in this paper to show the capability of these systems once well applied in a hot-humid climate.
基金Supported by the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB42000000)the National Natural Science Foundation of China(No.32071577)+2 种基金the International Partnership Program of Chinese Academy of Sciences(No.GJHZ2039)the Shandong Provincial Natural Science Foundation(No.ZR201911130493)the Taishan Industrial Experts Program(No.Tscy20200102)。
文摘During low tide,the intertidal seagrass Enhalus acoroides is often exposed to high light and desiccation,which can seriously threaten its survival,at least partly by inhibiting photosystem Ⅱ(PSⅡ)activity.The response of leaves of E.acoroides to high light and desiccation was compared for seedlings and mature plants.Results show that the resistance of seedling and mature leaves to high light was quite similar,but to desiccation was very different.Seedling leaves were more sensitive to desiccation than the mature plant leaves,but had better water retention.The damage of desiccation to seedling leaves was mainly caused by dehydration,whereas that to mature plant leaves was caused by hypersaline toxicity.The recovery rate of PSⅡ of seedling leaves was significantly slower than that of the mature plants after the stresses disappeared,which may at least partly contribute to seedling mortality in the wild.In addition,compared to high light,desiccation seriously inhibited the recovery rate of PSⅡ activities even if the leaves became fully rehydrated to their normal relative water content(RWC)in the following re-immersion.Desiccation inhibited the recovery rate of RC/CS_(M)(reaction center per cross section(at t=t_(Fm)))to decrease the production of assimilatory power,which maybe the cause of the slower PSⅡ recovery in desiccation treatments.This study demonstrates that desiccation particularly coupling with high light have a very negative ef fect on the PSⅡ of E.acoroides during low tide and the sensitivity of seedlings and mature plants to desiccation is significantly different,which have important reference significance to choose an appropriate transplanting depth where seedlings and mature plants of E.acoroides not only receive sufficient light for growth,but also that minimize desiccation stress during low tide.
基金To the Foundation for Support of Higher Education—CAPES the partial funding of research and the receive of the scholarship to the first authorThe National Council for Scientific and Technological Development—CNPq the receive of productivity in research grants to the second and sixth author.
文摘The pre-harvest application of herbicides may impair seed quality. This way, this paper was conducted to evaluate the effects of the application of desiccant herbicides on the physiological quality of pigeonpea seeds. Six batches of seeds from plants desiccated with glyphosate were evaluated at doses: 1.125 (B1), 1.5 (B2) and 1.875 L·ha-1 (B3);and Gramocil (20% Paraquat + 10% Diurom) at doses: 1.5 (B4) and 2 L·ha-1 (B5), and a control which received no application (B6). Seed viability was assessed through the germination standard test, and vigor through the first germination count, accelerated aging, electrical conductivity, seedling length, seedling dry matter and biomass density tests. The experimental design was the completely randomized, with four replications. Data were submitted to variance analysis, and when significant effects were observed, the Scott- Knott test was carried out at 5% probability using the SISVAR 5.1 software. The results showed that: a) the application of 1.875 L·ha-1 of glyphosate was harmful to pigeonpea seed viability and vigor, evaluated through the accelerated aging test;b) applications of glyphosate in a 1.875 L·ha-1 dose and Gramocil in 2 L·ha-1 resulted in low vigor according to the electrical conductivity test of seeds;and c) the seed vigor measured by the first count, seedling length, seedling dry matter and biomass density test was not influenced by the type of desiccant applied.
基金Sponsored by 2022 Teaching Reform Project of Lingnan Normal University(000302201830)2022 Model Course of Lingnan Normal University(LingShiJiaoWu(2014)No.125)2023 Undergraduate Students’Innovation and entrepreneurship Planning of Lingnan Normal University(X202310579049X).
文摘Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affiliated product will win the attention of parents.Against the background of consumption upgrading,consumers have had higher requirements on the humanization and safety design of products.Most of milk powder spoons on the market are plastic,and the disposal of waste milk powder spoon has gradually become a burden for the environment.Based on the environment-friendly and developmental concept,and also the characteristics of infant development,this paper proposed the“in-one”design,applied color and tactile designs into the milk powder design,chose food grade silicone to make the milk powder spoon not only a spoon but also a baby teether toy,so as to expand the service life and functions of the product,meet the requirements of saving energy,protecting environment and developing circular economy,which also to some extent reduces the burden on environment brought by plastics,improves the efficiency of junk recycling,and meet the individualized needs of consumers.