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BrWax1 function in wax biosynthesis was verified by allelic mutations in Chinese cabbage
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作者 Gengxing Song Xiaoli Tang +4 位作者 Chuanhong Liu Jiaqi Zou Shiyao Dong Jie Ren Hui Feng 《Horticultural Plant Journal》 2025年第3期1377-1380,共4页
Plants possess a hydrophobic layer of wax on their aerial surface,consisting mainly of amorphous intra-cuticular wax and epicuticular wax crystals(Kunst and Samuels,2003).This waxy coating contains a wide variety of v... Plants possess a hydrophobic layer of wax on their aerial surface,consisting mainly of amorphous intra-cuticular wax and epicuticular wax crystals(Kunst and Samuels,2003).This waxy coating contains a wide variety of very-long-chain fatty acids(VLCFAs)and their derivatives,including alkanes,alcohols,aldehydes,esters,and ketones. 展开更多
关键词 hydrophobic layer wax aerial surface hydrophobic layer waxy coating Chinese cabbage brwax allelic mutations wax biosynthesis
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Predicting Marine Fuels with Unusual Wax Appearance Temperatures Using One-Class Support Vector Machines
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作者 Njideka Chima-Amaeshi Chris O’Malley Mark Willis 《哈尔滨工程大学学报(英文版)》 2025年第6期1208-1217,共10页
Accurate and robust detection of wax appearance(a medium-to high-molecular-weight component of crude oil)is crucial for the efficient operation of hydrocarbon transportation.The wax appearance temperature(WAT)is the l... Accurate and robust detection of wax appearance(a medium-to high-molecular-weight component of crude oil)is crucial for the efficient operation of hydrocarbon transportation.The wax appearance temperature(WAT)is the lowest temperature at which the wax begins to form.When crude oil cools to its WAT,wax crystals precipitate,forming deposits on pipelines as the solubility limit is reached.Therefore,WAT is a crucial quality assurance parameter,especially when dealing with modern fuel oil blends.In this study,we use machine learning via MATLAB’s Bioinformatics Toolbox to predict the WAT of marine fuel samples by correlating near-infrared spectral data with laboratory-measured values.The dataset provided by Intertek PLC-a total quality assurance provider of inspection,testing,and certification services-includes industrial data that is imbalanced,with a higher proportion of high-WAT samples compared to low-WAT samples.The objective is to predict marine fuel oil blends with unusually high WAT values(>35℃)without relying on time-consuming and irregular laboratory-based measurements.The results demonstrate that the developed model,based on the one-class support vector machine(OCSVM)algorithm,achieved a Recall of 96,accurately predicting 96%of fuel samples with WAT>35℃.For standard binary classification,the Recall was 85.7.The trained OCSVM model is expected to facilitate rapid and well-informed decision-making for logistics and storage when choosing fuel oils. 展开更多
关键词 Marine fuel One-class support vector machines wax appearance temperature wax Machine learning
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Genome-wide analysis of the MYB gene family and functional analysis of Bh MYB79 in wax gourd 被引量:1
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作者 Yulei Qian Jinqiang Yan +6 位作者 Chen Luo Yan Li Yongguan Wu Wenrui Liu Wei Liu Dasen Xie Biao Jiang 《Horticultural Plant Journal》 2025年第2期788-803,共16页
Wax gourd(Benincasa hispida)is an important cucurbit crop with economic and medicinal value.The myeloblastosis(MYB)gene family is one of the largest gene families in plants and regulates various biological processes,w... Wax gourd(Benincasa hispida)is an important cucurbit crop with economic and medicinal value.The myeloblastosis(MYB)gene family is one of the largest gene families in plants and regulates various biological processes,whereas the MYB gene family has not been systematically studied in wax gourd.In this study,we performed genome-wide identification of the MYB gene family in wax gourd and analyzed their phylogenetic relationship,MYB DNA-binding domain(MYB DBD),gene structure,protein motif,synteny,duplication mode and expression pattern.As a result,a total of 215 BhMYB genes(BhMYBs)were identified,belonging to four subfamilies:1R-,2R-,3R-and 4R-MYB subfamilies.Genes of 1R-MYB subfamily and 2R-MYB subfamily were subdivided into different subgroups respectively.The analysis of MYB DBD,gene structure and protein motif showed that the most genes in the same subgroup had similar characteristics and the 2R-MYB genes were more conserved than the 1R-MYB genes.Interestingly,the long terminal retrotransposons(LTR-RTs)were found in the long introns of several BhMYBs.The results of synteny analysis showed that there were more syntenic gene pairs between wax gourd and other cucurbit crops,while the least number of syntenic gene pairs existed between wax gourd and rice.Gene duplication was the main reason for the expansion of the MYB gene family in wax gourd,with the transposed duplication(TRD)mode contributing more.All duplication BhMYB genes were under purifying selection pressure.Further expression analysis showed that many BhMYBs exhibited obvious tissue-specific expression and several BhMYBs were significantly induced by one or more abiotic stresses.BhMYB79 was particularly expressed in roots and significantly induced by salt,drought,cold and heat stresses,overexpression of which led to reduced tolerance to salt stress in Arabidopsis.In conclusion,our results provide a systematic analysis of wax gourd MYB gene family and facilitate the biological role study of BhMYB79 during wax gourd salt stress response process. 展开更多
关键词 wax gourd MYB gene family Abiotic stress Bioinformatic analysis BhMYB79
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Study on surface structure characterization and stability of α-AlH_(3) coated with paraffin wax
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作者 WANG Wei QIN Mingna +4 位作者 SHI Qiang TANG Wang CHEN Yajie ZHANG Yan GUO Tao 《火箭推进》 北大核心 2025年第5期137-144,共8页
Alpha-aluminum hydride(α-AlH_(3))is usually metastable due to the small enthalpy of formation,poor stability,high chemical activity,sensitivity to moisture and easy combination with water in the air.In order to inhib... Alpha-aluminum hydride(α-AlH_(3))is usually metastable due to the small enthalpy of formation,poor stability,high chemical activity,sensitivity to moisture and easy combination with water in the air.In order to inhibit the hygroscopicity ofα-AlH_(3) and improve its storage and stability,paraffin wax(PW)is selected as the coating material,and the solvent/non-solvent method is usually used to coat the surface ofα-AlH_(3).The structure and topography ofα-AlH_(3) before and after being coated by PW were characterized by Fourier transform infrared spectroscopy(FT-IR),X-ray diffractometer(XRD),X-ray electron spectroscopy(XPS),elemental analysis,and scanning electron microscopy(SEM).The results show that PW can form a uniform and complete coating layer on the surface ofα-AlH_(3),and the crystal structure and morphology of theα-AlH_(3) coated by PW are not changed.The moisture absorption weight gain rate is reduced from 12%to 0.8%,and the hygroscopicity is greatly reduced.Furthermore,theα-AlH_(3) coated by PW also showed excellent performance in resisting water erosion after theα-AlH_(3) coated by PW,and the hydrophobic angle increases from 27°to 98°after theα-AlH_(3) surface being coated by PW. 展开更多
关键词 α-AlH_(3) paraffin wax STABILITY
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BoaCRTISO regulates the color and glossiness of Chinese kale through its effects on pigment,abscisic acid,and cuticular wax biosynthesis
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作者 Chenlu Zhang Ling Li +9 位作者 Yutong Zhang Qiannan Liang Sha Luo Zhi Huang Huanxiu Li Victor Hugo Escalona Zhifeng Chen Fen Zhang Yi Tang Bo Sun 《Horticultural Plant Journal》 2025年第6期2137-2148,共12页
Carotenoid isomerase(CRTISO)is an important enzyme in carotenoid biosynthesis,and it catalyzes the conversion of lycopene precursors to lycopene in several plant species.However,the role of CRTISO in other biochemical... Carotenoid isomerase(CRTISO)is an important enzyme in carotenoid biosynthesis,and it catalyzes the conversion of lycopene precursors to lycopene in several plant species.However,the role of CRTISO in other biochemical processes during plant growth and development remains unclear.Here,we showed that Chinese kale boacrtiso mutants have distinctive characteristics,including a yellowgreen hue and glossy appearance,and this contrasts with the dark green and glaucous traits observed in wild-type(WT)plants.Analysis of pigments in mutants revealed that the reduction in the content of carotenoids and chlorophylls contributed to the yellow-green coloration observed in mutants.An examination of cuticular waxes in Chinese kale indicated that there was a decrease in both the total wax content and the content of individual waxes in boacrtiso mutants(bearing a mutation of BoaCRTISO),which may be caused by the decrease of abscisic acid(ABA)content.The expression of carotenoid,chlorophyll,ABA,and wax biosynthesis genes was downregulated in boacrtiso mutants.This finding confirms that BoaCRTISO regulates the biosynthesis of pigments,ABA,and cuticular waxes in Chinese kale.Our results provide new insights into the interplay between plant pigment and cuticular wax metabolic pathways in Brassica vegetables. 展开更多
关键词 BoaCRTISO Chinese kale Carotenoids Chlorophylls Cuticular waxes Synergistic regulation
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Synergistic impact of Md ERF2 and Md PUB17 on the biosynthesis of wax in apple epidermis
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作者 Meng Lv Xinhua Zhang +4 位作者 Jin Shang Yanfang Zhang Yefei Gu Xiaoan Li Fujun Li 《Horticultural Plant Journal》 2025年第4期1429-1439,共11页
The synergistic regulatory effect of the ethylene transcription factor MdERF2 and ubiquitin ligase MdPUB17 on apple(Malus domestica)epidermal wax was examined by transferring the pRI101-MdPUB17-MdERF2 dual overexpress... The synergistic regulatory effect of the ethylene transcription factor MdERF2 and ubiquitin ligase MdPUB17 on apple(Malus domestica)epidermal wax was examined by transferring the pRI101-MdPUB17-MdERF2 dual overexpression vector(PUB17-ERF2),the empty vector(pRI101),the pRI101-MdPUB17 overexpression vector(PUB17),and the pRI101-MdERF2 overexpression vector(ERF2)into Agrobacterium tumefaciens,respectively,to infect apple callus and fruits with water as the control(CK).The levels of expression of the genes related to the biosynthesis,transport,composition,content,and structure of wax in the callus and/or fruits were studied under different treatments.The synergistic treatment of PUB17-ERF2 resulted in a decrease in the expression levels of MdCER1,MdCER6,MdLACS2,MdWSD1,MdABCG11,MdPAS2,MdFATB,and MdKASII genes as induced by the sole treatment of ERF2.Moreover,in the treatment of PUB17-ERF2,the mass distribution density of the wax was observed to be intermediate between the ERF2 and PUB17 treatments.Furthermore,ERF2 was found to increase the contents of alkanes,alcohols,and ketones,while significantly decreasing the contents of fatty acids and esters.In contrast,PUB17 responded oppositely.When treated with PUB17-ERF2,the effects of PUB17 and ERF2 were observed to counteract each other,which resulted in intermediate levels of these compounds.Additionally,the fruit in the ERF2,PUB17 and PUB17-ERF2 treatments had a different waxy microstructure.Overall,the findings indicate that both ERF2 and PUB17 have an impact on the gene expression,wax composition,content,and microstructure in apple epidermis.Importantly,the co-expression of MdPUB17 and MdERF2 demonstrates their synergistic regulation of the biosynthesis of wax in the apple epidermis. 展开更多
关键词 Malus domestica wax MdERF2 MdPUB17 UBIQUITINATION
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Study on the Breaking Force and Efficacy Evaluation of Lipsticks Containing Carnauba Wax and Shea Butter
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作者 Zi Yusha Liu Jianwei +4 位作者 Jiang Xiuyu Hu Weiren Sheng Wenli Gui Yuhao Peng Xianwu 《China Detergent & Cosmetics》 2025年第2期56-61,共6页
Starting from the perspective of formula and efficacy,orthogonal experiments were first performed to explore the optimal ratio of three raw materials that potentially affect breaking force of lipsticks,verification ex... Starting from the perspective of formula and efficacy,orthogonal experiments were first performed to explore the optimal ratio of three raw materials that potentially affect breaking force of lipsticks,verification experiment on humans was then conducted to test the efficacy of the lipstick formula.Results showed that when the ratio of carnauba wax,shea butter and myristyl isopropyl ester was 3∶7∶3,the breaking force was optimal.After the subjects used the lipstick formula for 14 days,the moisture content of the lip stratum corneum significantly increased by 23.51% (P﹤0.05),the transepidermal water loss (TEWL) rate significantly decreased by 20.61%,the skin glossiness increased significantly by 9.88%,and the skin scale index decreased significantly by 55.76%. 展开更多
关键词 carnauba wax shea butter breaking strength lipsticks
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MdERF2 regulates cuticle wax formation by directly activating MdLACS2, MdCER1 and MdCER6 of apple fruit during postharvest
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作者 Xinyue Zhang Xinhua Zhang +6 位作者 Wenwen Sun Meng Lü Yefei Gu Sarfaraz Hussain Xiaoan Li Maratab Ali Fujun Li 《Journal of Integrative Agriculture》 2025年第6期2229-2239,共11页
Ethylene response factors 2(ERF2) are essential for plant growth, fruit ripening, metabolism, and resistance tostress. In this study, the expression levels of the genes for MdERF2 implicated in the biosynthesis, compo... Ethylene response factors 2(ERF2) are essential for plant growth, fruit ripening, metabolism, and resistance tostress. In this study, the expression levels of the genes for MdERF2 implicated in the biosynthesis, compositionand ultrastructure of fruit cuticular wax in apple(Malus domestica) were studied by the transfection of apple fruitand/or calli with MdERF2-overexpression(ERF2-OE) and MdERF2-interference(ERF2-AN) vectors. In addition,the direct target genes of MdERF2 related to wax biosynthesis were identified using electrophoretic mobility shiftassays(EMSAs) and dual-luciferase reporter(DLR) assays. The findings indicated that the expression levels offour wax biosynthetic genes, long-chain acyl-CoA synthetase 2(MdLACS2), eceriferum 1(MdCER1), eceriferum4(MdCER4), and eceriferum 6(MdCER6), were upregulated by ERF2-OE. In contrast, the expression levels ofthese genes were inhibited when MdERF2 was silenced. Furthermore, the overall structure and accumulationof fruit cuticular wax were influenced by the expression level of MdERF2. Treatment with ERF2-OE significantlyincreased the proportions of alkanes and ketones and reduced the proportions of fatty acids and esters. In addition,the EMSAs and DLR assays demonstrated that MdERF2 could bind directly to GCC-box elements in the promotersof MdLACS2, MdCER1, and MdCER6 to activate their transcription. These results confirmed that MdERF2 targetsthe up-regulation of expression of the MdLACS2, MdCER1, and MdCER6 genes, thereby altering the composition,content, and microstructure of apple epidermal wax. 展开更多
关键词 apple fruit wax ethyleneresponsefactor2 targetgenes
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Meta-analysis of the clinical efficacy of wax therapy combined with conventional pharmacotherapy in rheumatoid arthritis treatment
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作者 Wangxing Zeng Qian Deng +4 位作者 Zining Peng Fanyu Meng Weitian Yan Nian Liu Jiangyun Peng 《Journal of Chinese Pharmaceutical Sciences》 2025年第3期284-292,共9页
This study aimed to systematically evaluate the clinical efficacy of combining wax therapy with conventional drug therapy for rheumatoid arthritis(RA)and to provide evidence supporting its clinical application.A compr... This study aimed to systematically evaluate the clinical efficacy of combining wax therapy with conventional drug therapy for rheumatoid arthritis(RA)and to provide evidence supporting its clinical application.A comprehensive search was conducted across PubMed,Cochrane Library,China Biomedical Literature Database(CBM),China National Knowledge Infrastructure(CNKI),Wanfang,and VIP databases from their inception to May 2024.Randomized controlled trials(RCTs)investigating the combination of wax therapy and conventional drug therapy for RA were included in the analysis.Statistical analysis was performed using Review Manager 5.3 software.Nine studies,encompassing a total of 843 patients,were included.The results demonstrated that the combination therapy significantly improved clinical efficacy compared to conventional drug therapy alone[RR=1.22,95%CI(1.11,1.34)].Moreover,the combination therapy led to notable improvements in DAS 28 scores[MD=-0.90,95%CI(-1.23,-0.57),P<0.00001],VAS scores[MD=-0.90,95%CI(-1.13,-0.66),P<0.00001],reduction in joint tenderness[MD=-1.27,95%CI(-1.81,-0.72),P<0.00001],decreased duration of morning stiffness[MD=-25.47,95%CI(-34.33,-16.61),P<0.00001],and lowered C-reactive protein levels[MD=-6.29,95%CI(-12.02,-0.57),P<0.05].In conclusion,wax therapy combined with conventional anti-rheumatic drugs significantly enhanced the clinical outcomes for RA patients by alleviating symptoms,reducing joint pain and morning stiffness,and decreasing inflammatory markers more effectively than conventional drug therapy alone. 展开更多
关键词 Rheumatoid arthritis wax therapy Clinical effects META-ANALYSIS
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Development of a SGJ-1 of Water-Based Anti-Wax Agent
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作者 Lejun Liao Wenzhe Han +3 位作者 Qichao Cao Xintong Li Li He Song Wang 《Open Journal of Yangtze Oil and Gas》 2021年第2期72-83,共11页
The phenomenon of petroleum wax deposition is very common during oil well production. When the wax molecule condenses on the surface of the pipeline, it will hinder the exploitation of crude oil, reduce the recovery r... The phenomenon of petroleum wax deposition is very common during oil well production. When the wax molecule condenses on the surface of the pipeline, it will hinder the exploitation of crude oil, reduce the recovery rate of crude oil, and may lead to the blockage of the pipeline when it is serious, so that the oil recovery work will stop. This phenomenon can be obviously changed by using wax cleaning agent. However, the low ignition point and toxicity of oil-based wax remover are not conducive to oil recovery. Therefore, a new water-based paraffin remover SGJ-1 was developed in this paper. The best formula is: wax dispersant 15%, wetting reversion agent 1%, sodium silicate 1%, alcohol cosolvent 8% and 75% water. Condensation point, wax dissolution rate and anti-wax performance of SGJ-1 water-based dewaxing and anti-waxing agent were tested by self-assembly testing device. The experimental results show that the condensation point of SGJ-1 is -34°C, the viscosity reduction effect is good under 35°C, and the wax dissolution rate is 0.0512 g/min, The highest wax prevention rate can reach 89.58% and the wax removal and wax prevention ability is excellent. Compared with other paraffin removers, SGJ-1 can also reduce the viscosity of crude oil, so it has a good development prospect. 展开更多
关键词 Water-Based Anti-wax Agent Oil Well waxing wax Dissolution Rate Anti-wax Rate Performance Evaluation
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Effect of surfactants and their blend with silica nanoparticles on wax deposition in a Malaysian crude oil 被引量:6
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作者 Zhen Hao Lim Hikmat Said Al Salim +2 位作者 Norida Ridzuan Ronald Nguele Kyuro Sasaki 《Petroleum Science》 SCIE CAS CSCD 2018年第3期577-590,共14页
The present study investigated the wax deposition tendencies of a light Malaysian crude oil(42.4° API), and the wax inhibiting potential of some surfactants and their blends with nanoparticles. With the knowled... The present study investigated the wax deposition tendencies of a light Malaysian crude oil(42.4° API), and the wax inhibiting potential of some surfactants and their blends with nanoparticles. With the knowledge that the majority of the wax inhibition research revolved around polymeric wax inhibitors, which cause environmental issues, we highlighted the potential of surfactants and their blend with SiO2 nanoparticles as wax deposition inhibitors. Different surfactants including oil-based, silane-based, Gemini and bio-surfactants were considered as primary surfactants. The primary surfactants and their respective blends at a concentration of 400 ppm were screened as wax inhibitor candidates using cold finger apparatus. The screening results showed a significant influence on the paraffin inhibition efficiency on wax deposition by using 400 ppm of silane-based surfactant, which decreased the wax deposition up to 53.9% as compared to that of the untreated crude oil. The inhibition efficiency among the silane-based surfactant(highest) and bio-surfactant(lowest)revealed an appreciable difference up to 36.5%. Furthermore, the wax from the treated sample was found to deposit in a thin gel-like form, which adhered inadequately to the surface of the cold finger. A further investigation by blending the 400 ppm silane-based surfactant with a 400 ppm SiO2 nanoparticle suspension in a load ratio of 3:1 found that the wax inhibition decreased up to 81% as compared to the scenario when they were not added. However, we have shown that the synergy between the silane-based surfactant and the nanoparticles is influenced by the concentration and load ratio of surfactant and nanoparticles, residence time, differential temperature and rotation rate. 展开更多
关键词 Cold finger Nanoparticles wax deposition wax inhibitor Surfactant wax appearance temperature
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Physical properties of wax deposits on the walls of crude pipelines 被引量:3
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作者 Huang Qiyu Wang Jifeng Zhang Jinjun 《Petroleum Science》 SCIE CAS CSCD 2009年第1期64-68,共5页
Wax deposits on the wall of a crude oil pipeline are a solid wax network of fine crystals, filled with oil, resin, asphaltene and other impurities. In this paper, a series of experiments on wax deposition in a laborat... Wax deposits on the wall of a crude oil pipeline are a solid wax network of fine crystals, filled with oil, resin, asphaltene and other impurities. In this paper, a series of experiments on wax deposition in a laboratory flow loop were performed under different conditions (flow rate, temperature differential between crude oil and pipeline wall, and dissolved wax concentration gradient), and the wax deposits were analyzed, so quantitative relationships among wax content, wax appearance temperature (WAT), shear stress, and radial concentration gradient of dissolved wax at the solid/liquid interface were obtained. Finally, a model was established to predict WAT and the wax content of the deposit. 展开更多
关键词 Crude oil wax deposits pipeline wax content wax appearance temperature (WAT)
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Pre-heating temperature induced flowability and wax deposition characteristics of crude oil adding wax inhibitors 被引量:3
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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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一种枣植物组织改良的Steedman’s wax石蜡切片方法 被引量:1
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作者 马小玲 章英才 《植物研究》 北大核心 2025年第1期139-147,共9页
为了建立一种简便、安全、快速的石蜡制片方法,减少试验过程中有毒试剂二甲苯的使用,以4个时期灵武长枣(Ziziphus jujuba‘Lingwu Changzao’)的叶和果实为试验材料,采用改良的低熔点多酯蜡(Steedman’s wax)切片法观察不同时期的叶和... 为了建立一种简便、安全、快速的石蜡制片方法,减少试验过程中有毒试剂二甲苯的使用,以4个时期灵武长枣(Ziziphus jujuba‘Lingwu Changzao’)的叶和果实为试验材料,采用改良的低熔点多酯蜡(Steedman’s wax)切片法观察不同时期的叶和果实结构特征,包括采用改良包埋试剂,省略二甲苯透明步骤,缩短试验过程,建立起一套可行的植物组织石蜡制片方法,并与常规石蜡切片方法比较,为研究植物组织结构特征提供新思路。结果表明:通过改良的低熔点多酯蜡切片法获得的叶片和果实组织的形态结构完整且染色清晰,该改良方法不但简化了试验步骤、缩短了制片周期,而且制得的切片质量与常规石蜡切片质量无差别,达到了优化试验步骤、避免二甲苯等有毒试剂使用、节省试验时间、整体上提高植物石蜡制片效率的目的,值得用于更多植物形态解剖学研究。 展开更多
关键词 低熔点多酯蜡 石蜡切片 解剖特征
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Steedman’s wax包埋切片DAPI染色法证实铝诱导花生根尖细胞程序性死亡 被引量:7
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作者 邓伦武 黄文静 +4 位作者 何海旺 何虎翼 李创珍 韦善清 何龙飞 《南方农业学报》 CAS CSCD 北大核心 2014年第8期1353-1357,共5页
【目的】检验Steedman’swax包埋切片DAPI染色法是否适用于观察花生根尖细胞核形态。【方法】分别采取100μmol/L AlCl3处理不同时间(0、4、8、12 h)后两个花生品种(铝敏感型中花2号和耐铝型99-1507)的根尖,经过Steedman’s wax包埋切... 【目的】检验Steedman’swax包埋切片DAPI染色法是否适用于观察花生根尖细胞核形态。【方法】分别采取100μmol/L AlCl3处理不同时间(0、4、8、12 h)后两个花生品种(铝敏感型中花2号和耐铝型99-1507)的根尖,经过Steedman’s wax包埋切片等一系列过程,利用荧光染料DAPI染色观察细胞核形态变化。【结果】100μmol/L AlCl3可引起花生根尖细胞核形态发生改变,核质浓缩、核边缘化、呈新月状等,具有明显的PCD特征。花生根尖细胞在铝胁迫下发生PCD,PCD程度与花生耐铝性呈负相关,与处理时间呈正相关。【结论】Steedman’swax包埋切片DAPI染色法是一种快速、高效的适用于观察花生根尖细胞核形态的方法。 展开更多
关键词 花生 铝胁迫 细胞程序性死亡 Steedman’s wax包埋切片 DAPI染色
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Determination of wax pattern die profile for investment casting of turbine blades 被引量:8
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作者 董一巍 卜昆 +1 位作者 窦杨青 张定华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期378-387,共10页
In order to conform to dimensional tolerances, an efficient numerical method, displacement iterative compensation method, based on finite element methodology (FEM) was presented for the wax pattern die profile desig... In order to conform to dimensional tolerances, an efficient numerical method, displacement iterative compensation method, based on finite element methodology (FEM) was presented for the wax pattern die profile design of turbine blades. Casting shrinkages at different positions of the blade which was considered nonlinear thermo-mechanical casting deformations were calculated. Based on the displacement iterative compensation method proposed, the optimized wax pattern die profile can be established. For a A356 alloy blade, substantial reduction in dimensional and shape tolerances was achieved with the developed die shape optimization system. Numerical simulation result obtained by the proposed method shows a good agreement with the result measured experimentally. After four times iterations, compared with the CAD model of turbine blade, the total form error decreases to 0.001 978 mm from the orevious 0.515 815 mm. 展开更多
关键词 turbine blade numerical simulation displacement field wax pattern die profile investment casting
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用对称透射二维WAXS强度研究PET取向非晶态结构 被引量:4
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作者 韩甫田 陈济舟 +2 位作者 王俊桥 伍宣池 宾仁茂 《物理化学学报》 SCIE CAS CSCD 北大核心 1996年第1期39-43,共5页
用对称透射法,测试聚酯(PET)取向非晶试样的二维广角X射线散射相干强度Ie(K,α),将不同方位角α上的Ie(K,α)非晶重叠峰曲线进行计算机分解,获得分子链间原子散射引起的二个峰为A(K=0.126)、B(K=0.169);分子链内原... 用对称透射法,测试聚酯(PET)取向非晶试样的二维广角X射线散射相干强度Ie(K,α),将不同方位角α上的Ie(K,α)非晶重叠峰曲线进行计算机分解,获得分子链间原子散射引起的二个峰为A(K=0.126)、B(K=0.169);分子链内原子散射引起的五个峰分别为C(K=0.304)、D(K=0.553)、E(K=0.374)、F(K=0.465)、G(K=0.606),K单位为nm-1.分析了它们的结构起源以及主要峰参数与α的关系,得到PET取向非晶态的细微结构信息. 展开更多
关键词 对称透射 聚酯 非晶态结构 waxS
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一种用于DAPI染色的方法——Steedman's wax包埋切片法 被引量:9
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作者 安丽华 尤瑞麟 《西北植物学报》 CAS CSCD 2004年第8期1367-1372,共6页
以植物的胚珠和子房为实验材料,介绍一种用Steedman swax包埋对组织切片中的细胞核进行DAPI染色的方法.Steedman swax作为一种低熔点多酯蜡,具有与石蜡相似的性质,切片方法同常规石蜡切片,适合于切成厚度大于5μm的连续切片.Steedman s... 以植物的胚珠和子房为实验材料,介绍一种用Steedman swax包埋对组织切片中的细胞核进行DAPI染色的方法.Steedman swax作为一种低熔点多酯蜡,具有与石蜡相似的性质,切片方法同常规石蜡切片,适合于切成厚度大于5μm的连续切片.Steedman swax包埋的切片能成功地进行DAPI染色.与用压片法和Technovit7100或GMA包埋切片法进行的DAPI染色相比,用Steedman swax包埋切片法进行的DAPI染色具有廉价、操作简便、可进行连续切片、图象清晰等优点,特别在植物细胞程序化死亡 PCD 的研究中及细胞核DNA含量测定方面,有着较大的应用价值和潜能. 展开更多
关键词 Steedman’s wax 组织切片 DAPI 细胞核
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3个水稻WAX2同源基因表达的组织特异性及逆境响应特征 被引量:3
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作者 高国赋 邹杰 +3 位作者 周小云 刘爱玲 魏宝阳 陈信波 《作物学报》 CAS CSCD 北大核心 2010年第8期1336-1341,共6页
利用拟南芥的WAX2基因序列BLAST检索出3个水稻同源基因,命名为OsWAX2-1、OsWAX2-2和OsWAX2-3,与拟南芥WAX2基因的同源性分别为56.0%、55.2%和52.0%;其预测的编码蛋白与WAX2蛋白的同源性分别为61.5%、60.5%和64.7%。这3个蛋白都分别存在... 利用拟南芥的WAX2基因序列BLAST检索出3个水稻同源基因,命名为OsWAX2-1、OsWAX2-2和OsWAX2-3,与拟南芥WAX2基因的同源性分别为56.0%、55.2%和52.0%;其预测的编码蛋白与WAX2蛋白的同源性分别为61.5%、60.5%和64.7%。这3个蛋白都分别存在4个跨膜结构区和1个甾醇去饱和酶的保守区,说明它们都属于跨膜蛋白并可能与角质层的蜡质合成有关。采用半定量RT-PCR方法检测3个OsWAX2基因在水稻不同部位的表达情况,及高温、低温、NaCl、PEG和ABA5种处理对3个OsWAX2基因在转录水平表达的影响。结果表明,3个OsWAX2基因在水稻中的表达存在时空差异,3个基因在水稻萌动的胚中表达量都很高,OsWAX2-3基因在叶中的表达量最高;3个OsWAX2基因对高温、低温、盐、干旱及ABA胁迫响应也存在差别,OsWAX2-1只在ABA处理时增强表达;OsWAX2-2受高温、低温、盐、干旱胁迫及ABA诱导并且响应迅速。这一结果为进一步研究OsWAX2基因在水稻生长发育过程及逆境胁迫下的功能与作用机制提供了参考。 展开更多
关键词 水稻 wax2同源基因 半定量RT-PCR 表达 逆境响应
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双轴拉伸PET薄膜成膜过程非晶区分子取向的WAXS研究 被引量:3
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作者 陈济舟 王俊桥 +2 位作者 韩甫田 伍宣池 蒋世承 《高分子学报》 SCIE CAS CSCD 北大核心 1991年第6期684-689,共6页
本文将常应用于小的角度范围(29_(CuK_α)<50°)的结晶峰和非晶峰的计算机分峰法,推广到PET薄膜的广角度散射范围(2θ_(CuK_α)=5°—140°)。通过对分离出来的表征非晶区分子链间分布的非晶主峰特征参数的分析,探讨了... 本文将常应用于小的角度范围(29_(CuK_α)<50°)的结晶峰和非晶峰的计算机分峰法,推广到PET薄膜的广角度散射范围(2θ_(CuK_α)=5°—140°)。通过对分离出来的表征非晶区分子链间分布的非晶主峰特征参数的分析,探讨了在特定拉伸条件下非晶区分子取向在成膜过程的变化。 展开更多
关键词 PET薄膜 分子取向 waxS 非晶区结构
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