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Preferentially selective extraction of lithium from spent LiCoO_(2)cathodes by medium-temperature carbon reduction roasting 被引量:1
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作者 Daixiang Wei Wei Wang +6 位作者 Longjin Jiang Zhidong Chang Hualei Zhou Bin Dong Dekun Gao Minghui Zhang Chaofan Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期315-322,共8页
Lithium recovery from spent lithium-ion batteries(LIBs)have attracted extensive attention due to the skyrocketing price of lithium.The medium-temperature carbon reduction roasting was proposed to preferential selectiv... Lithium recovery from spent lithium-ion batteries(LIBs)have attracted extensive attention due to the skyrocketing price of lithium.The medium-temperature carbon reduction roasting was proposed to preferential selective extraction of lithium from spent Li-CoO_(2)(LCO)cathodes to overcome the incomplete recovery and loss of lithium during the recycling process.The LCO layered structure was destroyed and lithium was completely converted into water-soluble Li2CO_(3)under a suitable temperature to control the reduced state of the cobalt oxide.The Co metal agglomerates generated during medium-temperature carbon reduction roasting were broken by wet grinding and ultrasonic crushing to release the entrained lithium.The results showed that 99.10%of the whole lithium could be recovered as Li2CO_(3)with a purity of 99.55%.This work provided a new perspective on the preferentially selective extraction of lithium from spent lithium batteries. 展开更多
关键词 spent LiCoO_(2)cathodes medium-temperature carbon reduction lithium extraction priority crystal transformation macro-scopic transport resistance
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Differences in leaf cuticular wax induced by whole-genome duplication in autotetraploid sour jujube
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作者 Meng Li Chenxing Zhang +5 位作者 Lu Hou Xinru Liu Hanqing Zhao Xiaoming Pang Wenhao Bo Yingyue Li 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期66-76,共11页
Drought-resistant plants exhibit strong water retention capability.In this regard,the autotetraploid sour jujube leaves exhibit better water retention than diploid leaves.Morphological comparisons and physiological co... Drought-resistant plants exhibit strong water retention capability.In this regard,the autotetraploid sour jujube leaves exhibit better water retention than diploid leaves.Morphological comparisons and physiological comparisons of diploid and autotetraploid leaves showed that the autotetraploid leaves had thicker leaf cuticles and more leaf wax accumulation than the diploid leaves,which could reduce cuticle permeability and improve the drought tolerance of leaves.In this study,the cuticular wax crystalloids on the adaxial and abaxial sides of young and mature jujube leaves were observed in the two ploidy types,and unique cuticular wax crystalloids covering a large area of the cuticle on autotetraploid sour jujube leaves may provide an advantage in reducing leaf non-stomata transpiration and improving plant drought tolerance.Based on the transcriptome,115 differentially expressed genes between diploids and autotetraploids were further analyzed and found to be involved in the accumulation of cuticular wax components,including terpenoids,fatty acids,and lipids,as well as ABC transporter and wax biosynthetic process.Finally,14 genes differentially expressed between glossy autotetraploid leaves and nonglossy diploid leaves,such as LOC107414787,LOC107411574 and LOC107413721,were screened as candidate genes by qRT-PCR analysis.This findings provided insights into how polyploidization improved drought tolerance. 展开更多
关键词 AUTOTETRAPLOID JUJUBE Drought tolerance Cuticular wax RNA-seq
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ZmCER1,a putative ECERIFERUM 1 protein in maize,functions in cuticular wax biosynthesis and bulliform cell development
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作者 Yan Zhao Qingzhi Liu +4 位作者 Xueran Wang Weixiao Zhang Wei Xu Yongzhong Zhang Baoshen Liu 《The Crop Journal》 SCIE CSCD 2024年第3期743-752,共10页
The cuticular wax,acting as the ultimate defense barrier,is essential for the normal morphogenesis of plant organs.Despite this importance,the connection between wax composition and leaf development has not been thoro... The cuticular wax,acting as the ultimate defense barrier,is essential for the normal morphogenesis of plant organs.Despite this importance,the connection between wax composition and leaf development has not been thoroughly explored.In this study,we characterized a new maize mutant,ragged leaf4(rgd4),which exhibits crinkled and ragged leaves starting from the sixth leaf stage.The phenotype of rgd4 is conferred by ZmCER1,which encoding an aldehyde decarbonylase involved in wax biosynthesis.ZmCER1 function deficient mutant displayed reduced cuticular wax density and disordered bulliform cells(BCs),while ZmCER1 overexpressing plants exhibited the opposite effects,indicating that ZmCER1 regulates cuticular wax biosynthesis and BCs development.Additionally,as the density of cuticular wax increased,the water loss rate of detached leaf decreases,suggesting that ZmCER1 is positively correlated with plant drought tolerance. 展开更多
关键词 Ragged leaf ZmCER1 Cuticular wax Bulliform cells
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Prediction Model of Wax Deposition Rate in Waxy Crude Oil Pipelines by Elman Neural Network Based on Improved Reptile Search Algorithm
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作者 Zhuo Chen Ningning Wang +1 位作者 Wenbo Jin Dui Li 《Energy Engineering》 EI 2024年第4期1007-1026,共20页
A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax depositi... A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy. 展开更多
关键词 waxy crude oil wax deposition rate chaotic map improved reptile search algorithm Elman neural network prediction accuracy
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Pre-heating temperature induced flowability and wax deposition characteristics of crude oil adding wax inhibitors 被引量:1
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作者 Bo Yao Hao-Ran Zhu +4 位作者 Bao-Dong Yan Chuan-Xian Li Fei Yang Guang-Yu Sun Hong-Bo Zeng 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2468-2478,共11页
This paper investigated the effects of pre-heating treatment temperatures(T_(pre))on the flowability and wax deposition characteristics of a typical waxy crude oil after adding wax inhibitors.It is found that there is... This paper investigated the effects of pre-heating treatment temperatures(T_(pre))on the flowability and wax deposition characteristics of a typical waxy crude oil after adding wax inhibitors.It is found that there is little difference in wax precipitation exothermic characteristics of crude oils at different T_(pre),as well as the wax crystal solubility coefficient in the temperature range of 25-30℃.For the undoped crude oil,the flowability after wax precipitation gets much improved and the wax deposition is alleviated as T_(pre)increasing.At T_(pre)=50℃,the viscosity and wax deposition rate of crude oil adding wax inhibitors are higher than those of the undoped crude oil.When the T_(pre)increases to 60,70,and 80℃,the flowability of the doped crude oil are largely improved and the wax deposition is suppressed with the T_(pre)increase,but the wax content of wax deposit increases gradually.It is speculated that,on the one hand,the T_(pre)increase helps the dispersion of asphaltenes into smaller sizes,which facilitates the co-crystallization with paraffin waxes and generates more aggregated wax crystal flocs.This weakens the low-temperature gel structure and increases the solid concentration required for the crosslink to form the wax deposit.On the other hand,the decrease in viscosity increases the diffusion rate of wax molecules and accelerates the aging of wax deposits.The experimental results have important guiding significance for the pipeline transportation of doped crude oils. 展开更多
关键词 Pre-heating treatment wax inhibitor FLOWABILITY wax deposition waxy crude oil
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Wax from Pyrolysis of Waste Plastics as a Potential Source of Phase Change Material for Thermal Energy Storage 被引量:1
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作者 Pin Jin Ong Zhi Xiong Jerry Heng +11 位作者 Zhenxiang Xing Hnin Yu Yu Ko Pei Wang Hongfei Liu Rong Ji Xizu Wang Beng Hoon Tan Zibiao Li Jian Wei Xu Xian Jun Loh Enyi Ye Qiang Zhu 《Transactions of Tianjin University》 EI CAS 2023年第3期225-234,共10页
Over the past half-century, plastic consumption has grown rapidly due to its versatility, low cost, and unrivaled functional properties. Among the diff erent implemented strategies for recycling waste plastics, pyroly... Over the past half-century, plastic consumption has grown rapidly due to its versatility, low cost, and unrivaled functional properties. Among the diff erent implemented strategies for recycling waste plastics, pyrolysis is deemed the most economical option. Currently, the wax obtained from the pyrolysis of waste plastics is mainly used as a feedstock to manufacture chemicals and fuels or added to asphalt for pavement construction, with no other applications of wax being reported. Herein, the thermal pyrolysis of three common waste polyolefin plastics: high-density polyethylene(HDPE), low-density polyethylene(LDPE), and polypropylene(PP), was conducted at 450 ℃. The waste plastics-derived waxes were characterized and studied for a potential new application: phase change materials(PCMs) for thermal energy storage(TES). Gas chromatography–mass spectrometry analysis showed that paraffin makes up most of the composition of HDPE and LDPE waxes, whereas PP wax contains a mixture of naphthene, isoparaffin, olefin, and paraffin. Diff erential scanning calorimetry(DSC) analysis indicated that HDPE and LDPE waxes have a peak melting temperature of 33.8 ℃ and 40.3 ℃, with a relatively high latent heat of 103.2 J/g and 88.3 J/g, respectively, whereas the PP wax was found to have almost negligible latent heat. Fourier transform infrared spectroscopy and DSC results revealed good chemical and thermal stability of HDPE and LDPE waxes after 100 cycles of thermal cycling. Performance evaluation of the waxes was also conducted using a thermal storage pad to understand their thermoregulation characteristics for TES applications. 展开更多
关键词 PYROLYSIS Waste plastics RECYCLING wax Phase change materials
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Emerging low-density polyethylene/paraffin wax/aluminum composite as a form-stable phase change thermal interface material 被引量:1
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作者 Chuanchang Li Weixuan Wang +2 位作者 Xiaoliang Zeng Chunxuan Liu Rong Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期772-781,共10页
Thermal interface materials(TIMs) play a vital role in the thermal management of electronic devices and can significantly reduce thermal contact resistance(TCR). The TCR between the solid–liquid contact surface is mu... Thermal interface materials(TIMs) play a vital role in the thermal management of electronic devices and can significantly reduce thermal contact resistance(TCR). The TCR between the solid–liquid contact surface is much smaller than that of the solid–solid contact surface, but conventional solid–liquid phase change materials are likely to cause serious leakage. Therefore, this work has prepared a new formstable phase change thermal interface material. Through the melt blending of paraffin wax(PW) and low-density polyethylene(LDPE), the stability is improved and it has an excellent coating effect on PW. The addition of aluminum(Al) powder improves the low thermal conductivity of PW/LDPE, and the addition of 15wt% Al powder improves the thermal conductivity of the internal structure of the matrix by 67%. In addition, the influence of the addition of Al powder on the internal structure, thermal properties, and phase change behavior of the PW/LDPE matrix was systematically studied. The results confirmed that the addition of Al powder improved the thermal conductivity of the material without a significant impact on other properties, and the thermal conductivity increased with the increase of Al addition. Therefore, morphologically stable PW/LDPE/Al is an important development direction for TIMs. 展开更多
关键词 paraffin wax low-density polyethylene phase change materials thermal interface materials form stability
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Kinetics of medium-temperature α-amylase hydrolyzed <i>Huai yam</i>powder
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作者 Juan Miao Yunchang Fan +1 位作者 Jingjing Li Dexue Fu 《Agricultural Sciences》 2013年第9期5-11,共7页
In order to learn the enzymatic characteristics of Huai yam powder with medium-temperatureα-amylase, effects of substrate concentration,enzyme concentration, pH and temperature wereinvestigated. The Michealis-Menten ... In order to learn the enzymatic characteristics of Huai yam powder with medium-temperatureα-amylase, effects of substrate concentration,enzyme concentration, pH and temperature wereinvestigated. The Michealis-Menten equationwas used to fit the kinetics of the hydrolysis reaction. Experimental results indicate that maximum rate (Vm) is 3.1588 mg/mL·min under the condition of 70&#176;C, pH 7.0 and 0.0200 mg/mL of enzyme concentration. The Michealis constant (Km) is 6.6641 mg/mL. The kinetic model, including the factors such as substrate concentration, enzyme concentration and temperature, was established for the hydrolysis reaction under the temperature range from 40&#176;C - 70&#176;C. 展开更多
关键词 Huai YAM medium-temperature Α-AMYLASE Hydrolysis KINETICS
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An optimized protocol using Steedman’s wax for high-sensitivity RNA in situ hybridization in shoot apical meristems and flower buds of cucumber
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作者 WANG Cui SUN Jin-jing +3 位作者 YANG Xue-yong WAN Li ZHANG Zhong-hua ZHANG Hui-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第2期464-470,共7页
In situ mRNA hybridization(ISH)is a powerful tool for examining the spatiotemporal expression of genes in shoot apical meristems and flower buds of cucumber.The most common ISH protocol uses paraffin wax;however,embed... In situ mRNA hybridization(ISH)is a powerful tool for examining the spatiotemporal expression of genes in shoot apical meristems and flower buds of cucumber.The most common ISH protocol uses paraffin wax;however,embedding tissue in paraffin wax can take a long time and might result in RNA degradation and decreased signals.Here,we developed an optimized protocol to simplify the process and improve RNA sensitivity.We combined embedding tissue in low melting-point Steedman’s wax with processing tissue sections in solution,as in the whole-mount ISH method in the optimized protocol.Using the optimized protocol,we examined the expression patterns of the CLAVATA3(CLV3)and WUSCHEL(WUS)genes in shoot apical meristems and floral meristems of Cucumis sativus(cucumber)and Arabidopsis thaliana(Arabidopsis).The optimized protocol saved 4–5 days of experimental period compared with the standard ISH protocol using paraffin wax.Moreover,the optimized protocol achieved high signal sensitivity.The optimized protocol was successful for both cucumber and Arabidopsis,which indicates it might have general applicability to most plants. 展开更多
关键词 CUCUMBER in situ hybridization Steedman’s wax paraffin wax
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Fischer-Tropsch wax catalytic cracking for the production of low olefin and high octane number gasoline: Process optimization and heat effect calculation
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作者 Mei Yang Gang Wang +2 位作者 Jian-Nian Han Cheng-Di Gao Jin-Sen Gao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1255-1265,共11页
To produce low olefin gasoline with high octane number by Fischer-Tropsch (F-T) wax fluid catalytic cracking (FCC) process, operating conditions optimization were carried out in the pilot-scale riser and turbulent flu... To produce low olefin gasoline with high octane number by Fischer-Tropsch (F-T) wax fluid catalytic cracking (FCC) process, operating conditions optimization were carried out in the pilot-scale riser and turbulent fluidized bed (TFB) FCC unit. The experimental results in the riser indicated that under the condition of low reaction temperature and regenerated catalyst temperature, large catalyst-to-oil weight ratio (C/O) and long reaction time, the gasoline olefin content could be reduced to 20.28 wt%, but there is large octane number loss owing to a great loss in high octane number olefin. Therefore, a novel FCC process using the TFB reactor was proposed to strengthen the aromatization reaction. The reaction performance of TFB reactor were investigated. The result demonstrated that the TFB reactor has more significant effect in reducing olefins and improving aromatics. At the expense of certain gasoline yield, the gasoline olefin content reduced to 23.70 wt%, aromatics content could increase to 26.79 wt% and the RON was up to 91.0. The comparison of reactor structure and fluidization demonstrated that the TFB reactor has higher catalyst bed density. The reaction heat and coke combustion heat was calculated indicating the feasibility of its industrial application of the TFB process. 展开更多
关键词 Fischer-Tropsch wax Catalytic cracking RISER TFB Gasoline olefin Reaction heat
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Overexpression of ZxABCG11 from Zygophyllum xanthoxylum enhances tolerance to drought and heat in alfalfa by increasing cuticular wax deposition
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作者 Linbo Liu Aike Bao +6 位作者 Hujun Li Wanpeng Bai Haishuang Liu Ye Tian Yiying Zhao Fangchen Xia Suomin Wang 《The Crop Journal》 SCIE CSCD 2023年第4期1140-1151,共12页
Drought and heat stresses cause yield losses in alfalfa,a forage crop cultivated worldwide.Improving its drought and heat tolerance is desirable for maintaining alfalfa productivity in hot,arid regions.Cuticular wax f... Drought and heat stresses cause yield losses in alfalfa,a forage crop cultivated worldwide.Improving its drought and heat tolerance is desirable for maintaining alfalfa productivity in hot,arid regions.Cuticular wax forms a protective barrier on aerial surfaces of land plants against environmental stresses.ABCG11encodes an ATP binding cassette(ABC) transporter that functions in the cuticular wax transport pathway.In this study,Zx ABCG11 from the xerophyte Zygophyllum xanthoxylum was introduced into alfalfa by Agrobacterium tumefaciens-mediated transformation.Compared to the wild type(WT),transgenic alfalfa displayed faster growth,higher wax crystal density,and thicker cuticle on leaves under normal condition.Under either drought or heat treatment in greenhouse conditions,the plant height and shoot biomass of transgenic lines were significantly higher than those of the WT.Transgenic alfalfa showed excellent growth and 50% greater hay yield than WT under field conditions in a hot,arid region.Overexpression of Zx ABCG11 up-regulated wax-related genes and resulted in more cuticular wax deposition,which contributed to reduction of cuticle permeability and thus increased water retention and photosynthesis capacity of transgenic alfalfa.Thus,overexpression of Zx ABCG11 can simultaneously improve biomass yield,drought and heat tolerance in alfalfa by increasing cuticular wax deposition.Our study provides a promising avenue for developing novel forage cultivars suitable for planting in hot,arid,marginal lands. 展开更多
关键词 ALFALFA ZxABCG11 Cuticular wax Yield Stress tolerance
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Wax deposition modeling in oil-water stratified pipe flow
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作者 Hui-Shu Liu Ji-Miao Duan +5 位作者 Jiang Li Jian Wang Hao Yan Ke-Yu Lin Ke-Cheng Gu Chang-Jun Li 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期526-539,共14页
Wax deposition in oil-water stratified flow is commonly encountered onshore and offshore oil production pipe systems,and typically reduces transportation capacity of oil.The accurate predicted model of wax deposition ... Wax deposition in oil-water stratified flow is commonly encountered onshore and offshore oil production pipe systems,and typically reduces transportation capacity of oil.The accurate predicted model of wax deposition has becomes an indispensable approach to design effective remediation strategies.However,a reliable mechanistic model for wax deposition prediction in oil-water two-phase stratified pipe flow is lacking to validate the deposition process.In this work,a three-dimensional(axial,radial,and angular)robust wax deposit model for oil-water stratified circular pipe flow was developed.The model of formation of a gel deposit based on the first principles of rheology was developed,associated with the results obtained from hydrodynamics and heat/mass transfer simulations.The predictions for wax deposition are found to compare satisfactorily with experimental data with two different oils for single phase and four different water cuts for oil-water stratified pipe flow.It can be seen from the wax gelation mechanism that an increase in water cut can help to reduce the wall/oil-deposit interface shear stress,thereby leading to an increase in the degree of gelation as well as the deposit rate.Furthermore,a local deposit analysis in the circumferential direction was conducted,for water cut 75%and total flow rate 5 m3/h,which provided insights to understand that the thickness on pipe wall was roughly uniformly distributed locates near the top of the pipe and the nearer the position gets close to two points,where the oil-water interface contacts the inner wall,the deposition thickness quickly dropped to 0.It was attributed to the fact that a roughly uniformly thickness far away from the oil-water interface contact the inner wall resulted in the slowly changes temperature along the circumferential pipe wall wetted by oil. 展开更多
关键词 wax deposition Oil-water flow Stratified flow Heat and mass transfer
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An Experimental Study on the Interaction between Hydrate Formation and Wax Precipitation in Waxy Oil-in-Water Emulsions
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作者 Xincan Song Lin Wang +2 位作者 Cheng Yu Jiaxin Chen Linjie Ma 《Energy Engineering》 EI 2023年第8期1837-1852,共16页
The coupled formation of wax crystals and hydrates is a critical issue for the safety of deep-sea oil and gas exploration and subsea transport pipeline flow.Therefore,this paper conducts an experimental study on the c... The coupled formation of wax crystals and hydrates is a critical issue for the safety of deep-sea oil and gas exploration and subsea transport pipeline flow.Therefore,this paper conducts an experimental study on the characteristics of methane hydrate formation in a water-in-oil(W/O)system with different wax crystal contents and explores the influence of different initial experimental pressures on the induction period and maximum rate of hydrate formation.The wavelet function was introduced to process the reaction rate and calculate the maximum speed of hydrate formation.Notably,the higher the pressure,the smaller the maximum rate of hydrate formation.We observed that wax crystal precipitation increases the viscosity of the emulsion,which limits the diffusion of gas in the liquid phase during hydrate nucleation and thus delays the hydrate nucleation.The methane gas precipitation also affects the remaining fraction’s wax content and therefore affects the wax precipitation.Secondary hydrate formation was observed several times during the experiment,increasing the risk of pipeline blockage.Overall,this work provides insights into the effect of wax crystal precipitation on hydrate behaviour that could facilitate flow assurance applications in subsea multiphase pipelines and inform the safe transportation of oil and gas pipelines. 展开更多
关键词 Methane hydrate wax diesel oil wavelet transform
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Application of Wax Therapy in Pain Care of Patients with Rheumatoid Arthritis
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作者 Li Wang Fan Fan Yanrui Ren 《Yangtze Medicine》 2023年第1期11-17,共7页
Objective: To investigate the effect of wax therapy in pain care of patients with rheumatoid arthritis. Methods: Convenience sampling method was used to select inpatients with rheumatoid arthritis admitted to the rheu... Objective: To investigate the effect of wax therapy in pain care of patients with rheumatoid arthritis. Methods: Convenience sampling method was used to select inpatients with rheumatoid arthritis admitted to the rheumatology and immunology department of a 3A hospital in Jingzhou City. 75 patients from January 2021 to June 2021 were selected as the control group, and 75 patients from January 2022 to June 2022 were selected as the observation group. The control group was given routine nursing, and the observation group was implemented wax therapy nursing on the basis of the control group. The relief of clinical symptoms (morning stiffness time, pain score) and quality of life score of the two groups were observed. Results: After intervention, there was statistical significance between the two groups (P Conclusion: Wax therapy can improve the time of morning stiffness, the degree of pain and the quality of life of patients with rheumatoid arthritis. 展开更多
关键词 wax Therapy Rheumatoid Arthritis Pain Care
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2010年以来国内外石蜡市场分析及展望
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作者 孔劲媛 缪超 +1 位作者 张强 孙守峰 《国际石油经济》 2024年第1期92-99,共8页
近些年欧美市场合成蜡和其他替代产品的发展,压缩了石蜡的消费增长空间。2020年新冠病毒疫情导致全球石蜡需求下降,消费规模退回到2015年的水平。2020—2025年全球石蜡需求将在低基数上稳定增长,但随着合成蜡和环境友好型包装物的使用增... 近些年欧美市场合成蜡和其他替代产品的发展,压缩了石蜡的消费增长空间。2020年新冠病毒疫情导致全球石蜡需求下降,消费规模退回到2015年的水平。2020—2025年全球石蜡需求将在低基数上稳定增长,但随着合成蜡和环境友好型包装物的使用增加,全球石蜡需求增长空间有限。中国是世界上重要的石蜡生产和出口国,石蜡及其制品的国外市场消纳度已达到70%左右。未来中国石蜡消费量将稳中趋升,预计2025年消费量在90万吨左右;生产企业继续减少,但总生产能力相对稳定。延伸石蜡产业链,提高石蜡制品附加值,做大国内市场,降低对国外市场的依赖程度,是中国石蜡市场未来的发展方向。 展开更多
关键词 石蜡市场 合成蜡 蜡烛 消费量 产量
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超声辅助水剂法提取硅藻土中玉米蜡脂的工艺优化
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作者 韩丹 孙立斌 +2 位作者 汪鸿 于殿宇 王俊国 《中国油脂》 CAS CSCD 北大核心 2024年第3期121-124,共4页
为了提高玉米油精炼的附加值,并实现硅藻土的可循环利用,以玉米油精炼副产物含蜡脂的硅藻土为原料,采用超声辅助水剂法提取玉米蜡脂,考察了不同提取条件对玉米蜡脂提取率的影响,并通过响应面法优化玉米蜡脂提取的工艺条件。结果表明:超... 为了提高玉米油精炼的附加值,并实现硅藻土的可循环利用,以玉米油精炼副产物含蜡脂的硅藻土为原料,采用超声辅助水剂法提取玉米蜡脂,考察了不同提取条件对玉米蜡脂提取率的影响,并通过响应面法优化玉米蜡脂提取的工艺条件。结果表明:超声辅助水剂法提取玉米蜡脂的最佳工艺条件为超声功率480 W、超声时间4 h、提取温度95℃、料液比1∶3,在此条件下玉米蜡脂提取率为(59.46±0.91)%。综上,超声辅助水剂法可以有效提取硅藻土中的玉米蜡脂。 展开更多
关键词 硅藻土 超声辅助法 水剂法 玉米蜡脂
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用于加热卷烟的石蜡改性二醋酸纤维素降温滤嘴的制备与表征
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作者 卢昕博 董晨晓 +5 位作者 徐建 肖卫强 徐生立 王骏 蒋健 郭杨龙 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期377-382,共6页
以二醋酸纤维素滤棒为载体,以食品级石蜡为相变吸热材料,采用浸渍法制备了石蜡/醋纤降温滤棒,研究了石蜡熔点和负载量对加热卷烟主流烟气温度的影响,并采用热重/差热分析仪(TG/DTA)、傅里叶变换红外光谱仪(FT-IR)、差示扫描量热仪(DSC)... 以二醋酸纤维素滤棒为载体,以食品级石蜡为相变吸热材料,采用浸渍法制备了石蜡/醋纤降温滤棒,研究了石蜡熔点和负载量对加热卷烟主流烟气温度的影响,并采用热重/差热分析仪(TG/DTA)、傅里叶变换红外光谱仪(FT-IR)、差示扫描量热仪(DSC)和场发射扫描电子显微镜(SEM)等技术对石蜡/醋纤滤棒进行了表征。石蜡/醋纤滤棒是通过醋纤滤棒的吸附作用完成复合,在抽吸过程中具有良好的热稳定性,当52~#石蜡乳化液质量分数为60%时,即石蜡负载量为35 mg时,由石蜡/醋纤滤棒组成的三段式降温滤嘴对主流烟气具有显著的降温效果,可将主流烟气温度从68℃降低到42℃。 展开更多
关键词 加热卷烟 石蜡 醋纤滤棒 降温滤嘴 主流烟气温度
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具有核壳结构的预分散C.I.颜料橙34的制备
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作者 张天永 王昱童 +3 位作者 刘万兴 李彬 姜爽 吕东军 《化学工业与工程》 CAS CSCD 北大核心 2024年第1期12-20,共9页
色母粒是传统预分散有机颜料剂型,制备工艺相对复杂,着色时过滤分散值较大,颜料分散性亟待提高。以3,3′-二氯联苯胺(DCB)和对甲苯基吡唑酮为原料,经重氮化偶合反应得到C.I.颜料橙34(PO34)与水的混合液,加热条件下使PO34与外层熔融的11... 色母粒是传统预分散有机颜料剂型,制备工艺相对复杂,着色时过滤分散值较大,颜料分散性亟待提高。以3,3′-二氯联苯胺(DCB)和对甲苯基吡唑酮为原料,经重氮化偶合反应得到C.I.颜料橙34(PO34)与水的混合液,加热条件下使PO34与外层熔融的110型聚乙烯蜡(PE)结合,获得了颗粒均匀、分散性好的预分散PO34新剂型(PPO34)。通过调控PE与PO34的质量比、PE的粒径、加热时间与加热温度、搅拌速率等实验条件,研究其对预分散颜料应用性能的影响规律。通过形貌、着色性能数据对比得到PPO34制备较适宜条件为:m(PE)∶m(PO34)为1∶1、41~60目PE、加热时间20 min、加热温度90℃、机械搅拌速率为200 r·min^(-1)。上述条件制得的PPO34粒径均一,具有明显核壳结构。与原始PO34相比,疏水性能显著增强,含水量低,过滤时间短,避免了生产中滤饼板结和强力粉碎产生的粉尘,更加环保高效;与传统色母粒相比,分散性能更好,在保持与原颜料相近的色光、明暗度、饱和度和色相等颜料性能前提下,提高了颜料着色强度,改进了其他多方面应用性能。 展开更多
关键词 C.I.颜料橙34 聚乙烯蜡 预分散 核壳结构 颜料改性
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表层蜡质结构及去蜡处理对李果实贮藏性的影响
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作者 周丹蓉 叶新福 +1 位作者 方智振 林炎娟 《东南园艺》 2024年第2期125-133,共9页
【目的】蜡质是植物表层重要的防御和保护层,探究不同李品种果实表层蜡质结构的差异及蜡质的去留对果实贮藏性的影响。【方法】选择福建主栽的两个李品种芙蓉李及油?为试验材料,通过扫描电镜观察成熟果实表层蜡质结构的差异,设置4℃、2... 【目的】蜡质是植物表层重要的防御和保护层,探究不同李品种果实表层蜡质结构的差异及蜡质的去留对果实贮藏性的影响。【方法】选择福建主栽的两个李品种芙蓉李及油?为试验材料,通过扫描电镜观察成熟果实表层蜡质结构的差异,设置4℃、25℃两个贮藏温度,试验保留蜡质和去蜡处理对果实贮藏性的影响。【结果】两种李的果皮蜡质结构均以直立片状晶体和颗粒状晶体为主,其中芙蓉李的直立片状晶体更厚,而油?的直立片状晶体边缘更规则、颗粒状晶体排列更紧密。芙蓉李和油?在4℃下贮藏35d,在25℃下分别贮藏12 d、21 d,果皮的去蜡处理对两种李果实贮藏时的腐烂率、失重率、硬度以及果肉的可溶性固形物含量、可滴定酸含量均有显著影响,去蜡处理加速了果实腐烂率、失重率的上升和硬度的下降,且在芙蓉李中的变幅更大、25℃贮藏时表现更突出。去蜡处理降低了芙蓉李贮藏中后期可溶性固形物含量的增加速度,促进了可滴定酸含量的下降速度;去蜡处理的油?在4℃贮藏中后期的可溶性固形物含量也低于保留蜡质处理、而可滴定酸含量高于保留蜡质处理(35 d除外)。【结论】果皮蜡质的存在有助于保持李果实的品质,且不同品种的蜡质结构差异对贮藏性有影响。这些发现可为李果实贮藏保鲜技术的开发提供参考。 展开更多
关键词 蜡质结构 去蜡 贮藏性
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含强化肋的PCM相变储热与传热特性数值研究
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作者 张永春 董文利 +3 位作者 孙涛 梁国安 尹迪 周小明 《南京师大学报(自然科学版)》 CAS 北大核心 2024年第2期8-16,共9页
为了有效提升PCM相变储热器的性能,本文采用多种金属翅片对相变过程进行强化,并采用焓-多孔介质模型对相变储热过程进行了数值模拟,分析了不同金属材料和不同基体孔隙率对相变储热及传热特性的影响.研究结果表明,采用金属泡沫强化翅片... 为了有效提升PCM相变储热器的性能,本文采用多种金属翅片对相变过程进行强化,并采用焓-多孔介质模型对相变储热过程进行了数值模拟,分析了不同金属材料和不同基体孔隙率对相变储热及传热特性的影响.研究结果表明,采用金属泡沫强化翅片能够增强导热和对流效应,优化流场对流涡分布,储热器相变储热时间大大缩短,耗时仅为无翅片工况的16.8%;采用铜金属泡沫翅片的储能效率略优于铝金属泡沫翅片,储热时间缩短3.47%;强化翅片孔隙率对储热性能影响较弱,孔隙率为0.4时最优,孔隙率为0.6时次之,孔隙率为0.8时最差. 展开更多
关键词 相变储能 金属泡沫 翅片 孔隙率 石蜡
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