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The Preliminary Study on Screening and Application of Phthalic Acid-Degrading Bacteria
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作者 Honghao Zhang Lin yang +3 位作者 Rubing Xu Yuxiao Sun yong yang Yanyan Li 《Advances in Microbiology》 CAS 2024年第4期226-239,共14页
Phthalic acid is a main pollutant, which is also an important reason for the continuous cropping effect of tobacco. In order to degrade the phthalic acid accumulated in the environment and relieve the obstacle effect ... Phthalic acid is a main pollutant, which is also an important reason for the continuous cropping effect of tobacco. In order to degrade the phthalic acid accumulated in the environment and relieve the obstacle effect of tobacco continuous cropping caused by the accumulation of phthalic acid in the soil. In this study, phthalate degrading bacteria B3 is screened from continuous cropping tobacco soil. The results of biochemical identification and 16sDNA comparison show that the homology between degrading bacterium B3 and Enterobacter sp. is 99%. At the same time, the growth of Enterobacter hormaechei subsp. B3 and the degradation of phthalic acid under different environmental conditions are studied. The results show that the environment with a temperature of 30˚C, PH of 7, and inoculation amount of not less than 1.2%, which is the optimal growth conditions for Enterobacter sp. B3. In an environment with a concentration of phthalic acid not exceeding 500 mg/L, Enterobacter sp. B3 has a better effect on phthalic acid degradation, and the degradation rate can reach 77% in 7 d. The results of indoor potting experiments on tobacco show that the degradation rate of phthalic acid by Enterobacter B3 in the soil is about 45%, which can reduce the inhibitory effect of phthalic acid on the growth of tobacco seedlings. This study enriches the microbial resources for degrading phthalic acid and provides a theoretical basis for alleviating tobacco continuous cropping obstacles. 展开更多
关键词 Phthalic Acid Degrading Bacteria Rhizosphere Soil
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低丰度致密砂岩天然气分布特征及充注过程半定量评价——以鄂尔多斯盆地定北地区上古生界为例
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作者 张小菊 邓虎成 +6 位作者 伏美燕 王付斌 段博瀚 徐争启 雍洋 李泓运 卢涛 《天然气工业》 EI CAS CSCD 北大核心 2024年第3期119-130,共12页
鄂尔多斯盆地致密砂岩气藏为天然气运移路径上的滞留气藏,气藏充注程度低、丰度低、产气量低、气水关系复杂,天然气是否有效充注、充注程度如何均不明确。为此,以鄂尔多斯盆地定北地区上古生界致密砂岩气藏为例,基于岩心、测井、地震、... 鄂尔多斯盆地致密砂岩气藏为天然气运移路径上的滞留气藏,气藏充注程度低、丰度低、产气量低、气水关系复杂,天然气是否有效充注、充注程度如何均不明确。为此,以鄂尔多斯盆地定北地区上古生界致密砂岩气藏为例,基于岩心、测井、地震、生产动态等资料,厘清了天然气分布特征,并综合烃源岩、砂体以及断裂分布空间组合关系,确定了天然气充注方式,再根据充注点、充注动力和阻力,确定了优势充注路径,最后开展了不同充注路径下的气水分布评价。研究结果表明:(1)上古生界致密砂岩气层主要为下二叠统太原组2段第2层(太2-2层)、第3层(太2-3层)与中二叠统下石盒子组1段,同时存在气层、气水同层以及水层,气水关系复杂,气井产量差异大,存在局部高产气井;(2)致密砂岩气藏天然气充注点可分为源储邻近充注点、近源充注点以及远源充注点3类,天然气充注方式可分为砂体源内充注、砂体叠置纵横扩散充注、储集体内断裂沟通跨砂体充注以及复合充注4类;(3)建立了天然气充注路径评价参数充注动力(P_(M))和充注阻力(P_(D)),P_(M)越小,充注动力越强,P_(D)越小,充注阻力越小,P_(M)大且P_(D)小,则充注动力损失小,从充注点到井点的充注动力最强、阻力最小,为天然气优势充注路径;(4)确定了4大类11小类气水分布类型和4类充注方式下气水分布规律,其中研究区西部源内充注、近源充注、断砂有利配置充注均可形成较高丰度的天然气富集,东西部远源充注和断砂较有利配置充注可形成较低丰度的天然气富集。结论认为,该研究成果不仅可以为该区目的层寻找充注程度更高的天然气富集区提供依据,也能够在低丰度气藏区的天然气充注优势区进行有效评价,较传统方法更加精细,更适合单个气藏的精细评价。 展开更多
关键词 鄂尔多斯盆地 定北地区 上古生界 太原组 下石盒子组 低丰度气藏 天然气充注 半定量评价
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Tissue distribution of cadmium and its effect on reproduction in Spodoptera exigua
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作者 Honghua Su Menglu Wu +3 位作者 yong yang Yan Deng Yizhong yang Qingming Sun 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期195-204,共10页
Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua... Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution. 展开更多
关键词 heavy metal pollution CADMIUM Spodoptera exigua tissue distribution REPRODUCTION
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Enhanced recovery of high-purity Fe powder from iron-rich electrolytic manganese residue by slurry electrolysis
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作者 Wenxing Cao Jiancheng Shu +5 位作者 Jiaming Chen Zihan Li Songshan Zhou Shushu Liao Mengjun Chen yong yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期531-538,共8页
Iron-rich electrolytic manganese residue(IREMR)is an industrial waste produced during the processing of electrolytic metal manganese,and it contains certain amounts of Fe and Mn resources and other heavy metals.In thi... Iron-rich electrolytic manganese residue(IREMR)is an industrial waste produced during the processing of electrolytic metal manganese,and it contains certain amounts of Fe and Mn resources and other heavy metals.In this study,the slurry electrolysis technique was used to recover high-purity Fe powder from IREMR.The effects of IREMR and H2SO4 mass ratio,current density,reaction temper-ature,and electrolytic time on the leaching and current efficiencies of Fe were studied.According to the results,high-purity Fe powder can be recovered from the cathode plate,and the slurry electrolyte can be recycled.The leaching efficiency,current efficiency,and purity of Fe reached 92.58%,80.65%,and 98.72wt%,respectively,at a 1:2.5 mass ratio of H2SO4 and IREMR,reaction temperature of 60℃,electric current density of 30 mA/cm^(2),and reaction time of 8 h.In addition,vibrating sample magnetometer(VSM)analysis showed that the coercivity of electrolytic iron powder was 54.5 A/m,which reached the advanced magnetic grade of electrical pure-iron powder(DT4A coercivity standard).The slurry electrolytic method provides fundamental support for the industrial application of Fe resource recovery in IRMER. 展开更多
关键词 iron-rich electrolytic manganese residue slurry electrolysis high-purity iron powder leaching efficiency current efficiency
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Adsorption,in vitro digestion and human gut microbiota regulation characteristics of three Poria cocos polysaccharides
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作者 Fangming Zhang Hui Zheng +10 位作者 Tao Zheng Pan Xu Yao Xu Yuxin Cao Fan Jia Yiqiong Zeng Yubing Fan Kai He Xinwen Dai Fengfei Hou yong yang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1685-1697,共13页
Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysacch... Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysaccharide(WSP)is extracted and applied for clinical application,while insoluble polysaccharide(alkali-soluble poria polysaccharide,ASP)is discarded as herb residue.However,the whole PC has also been historically utilized as functional herbal food.Considering the beneficial role of dietary fiber and the traditional use of PC,ASP may also contribute substantially to the therapy function of PC.Compared to WSP,little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide(CMP)which has been used as an antitumor adjuvant drug.In this study,the oil,cholesterol,metal ions and polyphenols adsorption ability,in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP,ASP and CMP were studied to evaluate the functional values of three P.cocos polysaccharides(PCPs).The results showed that all three PCPs had good adsorption capacity on cholesterol,polyphenols and metal ions(Cd^(2+)/Zn^(2+)/Mg^(2+)),among which ASP showed the highest capacity than WSP and CMP.The adsorption capacity of all three PCPs on heavy metal ions(Cd^(2+)/Zn^(2+))was stronger than that of non-heavy metal ions(Mg^(2+));The in vitro digestibility of all three PCPs was very low,but WSP was slightly higher than ASP and CMP;Moreover,the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota,among which ASP had the greatest influence.In general,ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful bacteria.The gut microbiota diversity of CMP was reduced,but the richness of probiotics,especially Parabacteroides distasonis was significantly enhanced compared with the ASP group,and the growth of harmful bacteria Klebsiella pneumoniae was inhibited after CMP treatment.The short-chain fatty acids(SCFAs)analysis results showed that all three PCPs could significantly promote the production of acetic acid,propionic acid and the total acid content compared with blank control group,and SCFAs producing activity was positively correlated with the proliferative capacity of probiotics.Taken together,the good adsorption characteristics and gut microbiota regulatory activity of ASP may lay foundation for its lipid-lowering and immune-improving function.Additionally,the probiotic effect of CMP and ASP indicated that except for only use the water extract of PC in clinic,CMP and ASP also can be used in healthcare to take full advantage of this valuable medicine. 展开更多
关键词 Poria cocos polysaccharides Alkali-soluble poria polysaccharide Carboxymethyl poria polysaccharide Adsorption characteristics In vitro simulated digestion In vitro simulated gut microbiota fermentation
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Arlenea delicata gen. et sp. nov., a new ephedroid plant from the Early Cretaceous Crato Formation, Araripe Basin, Northeast Brazil
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作者 Alita Maria Neves Ribeiro yong yang +3 位作者 Antonio Alamo Feitosa Saraiva Renan Alfredo Machado Bantim Joao Tavares Calixto Junior Flaviana Jorge de Lima 《Plant Diversity》 SCIE CAS CSCD 2024年第3期362-371,共10页
Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE China.However,few ephedroid macrofossils have been reported from South Amer... Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE China.However,few ephedroid macrofossils have been reported from South America.Herein,we describe a new plant of the family Ephedraceae,Arlenea delicata gen.et sp.nov.,from the Lower Cretaceous Crato Formation of the Araripe Basin,Northeast Brazil,based on the vegetative and reproductive structures.It has the typical morphological characteristics of ephedroid plants,including fertile reproductive branches,opposite phyllotaxy,terminal female cones,a sympodial branching system,longitudinally striated internodes,and swollen nodes.Our new finding is unusual in having inner chlamydosperms subtended by two pairs of bracts,reproductive units connected to branches through swollen receptacles and a smooth seed surface.This new ephedroid taxon from the Crato Formation increases our understanding of plant diversity of this group during the Early Cretaceous.Furthermore,the general morphology(fleshy bracts and enlarged receptacles)of this new fossil discovery indicates that seeds of this plant may have been dispersed by animals such as pterosaurs(mainly the Tapejaridae)and birds(Enantiornithes and Ornituromorpha).If true,this would explain the cosmopolitan distribution of Ephedraceae in the Lower Cretaceous. 展开更多
关键词 Early Cretaceous Gnetophytes Arlenea delicata Ephedrales Crato Formation
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Ultra‑Efficient and Cost‑Effective Platinum Nanomembrane Electrocatalyst for Sustainable Hydrogen Production
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作者 Xiang Gao Shicheng Dai +8 位作者 Yun Teng Qing Wang Zhibo Zhang Ziyin yang Minhyuk Park Hang Wang Zhe Jia Yunjiang Wang yong yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期95-110,共16页
Hydrogen production through hydrogen evolution reaction(HER)offers a promising solution to combat climate change by replacing fossil fuels with clean energy sources.However,the widespread adoption of efficient electro... Hydrogen production through hydrogen evolution reaction(HER)offers a promising solution to combat climate change by replacing fossil fuels with clean energy sources.However,the widespread adoption of efficient electrocatalysts,such as platinum(Pt),has been hindered by their high cost.In this study,we developed an easy-to-implement method to create ultrathin Pt nanomembranes,which catalyze HER at a cost significantly lower than commercial Pt/C and comparable to non-noble metal electrocatalysts.These Pt nanomembranes consist of highly distorted Pt nanocrystals and exhibit a heterogeneous elastic strain field,a characteristic rarely seen in conventional crystals.This unique feature results in significantly higher electrocatalytic efficiency than various forms of Pt electrocatalysts,including Pt/C,Pt foils,and numerous Pt singleatom or single-cluster catalysts.Our research offers a promising approach to develop highly efficient and cost-effective low-dimensional electrocatalysts for sustainable hydrogen production,potentially addressing the challenges posed by the climate crisis. 展开更多
关键词 PLATINUM Hydrogen evolution reaction Lattice distortion Heterogeneous strain
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The first mitogenome of Lauraceae(Cinnamomum chekiangense)
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作者 Changwei Bi Ning Sun +3 位作者 Fuchuan Han Kewang Xu yong yang David K.Ferguson 《Plant Diversity》 SCIE CAS CSCD 2024年第1期144-148,共5页
There are three distinct genetic systems in higher plants,the dominant nuclear genome and the semi-autonomous organelle genomes(plastids and mitochondria).In contrast to the conserved plastid genome(plastome),the plan... There are three distinct genetic systems in higher plants,the dominant nuclear genome and the semi-autonomous organelle genomes(plastids and mitochondria).In contrast to the conserved plastid genome(plastome),the plant mitochondrial genome(mitogenome)is characterized by an intriguing“evolutionary paradox”distinguished by a remarkably low mutation rate but with a significantly high rearrangement rate(Palmer and Herbon,1988;Lai et al.,2022). 展开更多
关键词 AUTONOMOUS distinguished Palmer
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Study on the Photosynthetic Characteristics of Six Varieties(Strains)in Chinese Chestnut
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作者 Lizhi FU yong yang +6 位作者 Xiaoxiao KANG Meng WANG Jing LIU Xuan WANG Dongsheng WANG Liyang YU Hai’e ZHANG 《Agricultural Biotechnology》 2024年第1期9-14,57,共7页
[Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis effici... [Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis efficiency breeding and application in Chinese chestnut.[Methods]Six Chinese chestnut varieties of Castanea mollissima‘Yanbao’,C.mollissima‘Yanqiu’,C.mollissima‘Yanchang’,C.mollissima‘Yanjia’,C.mollissima‘Qianxi 37’,and C.mollissima‘Hybrid 22’were used as the materials.Using the portable photosynthesis system Li-6400,we measured the photosynthetic characteristics and diurnal variation of leaf samples of six different chestnut varieties or strains.We fitted the light response curves and photosynthetic parameters using the leaf floating model.Additionally,we determined the chlorophyll content in the leaves using a UV-visible spectrophotometer.[Results]Among the six chestnut varieties or strains,‘Yanqiu’exhibited a significantly higher photosynthetic light saturation point(P LSP)compared to other five varieties,and‘Hybrid 22’ranked second,indicating that these two varieties had the strongest adaptation to high light intensity.The photosynthetic light compensation point(P LCP)of‘Yanchang’was significantly higher than other five varieties,and"Qianxi 37"ranked second,indicating that these two varieties had the strongest adaptation to low light intensity.Additionally,they exhibited higher chlorophyll content and maintained good photosynthetic characteristics even in shaded environments with weak light stress.Varieties‘Yanbao’and‘Yanjia’showed higher P LSP and lower P LCP,indicating that these two varieties have a wider range of adaptation to light intensity.They were capable of efficiently utilizing light across a broader spectrum of intensities.‘Yanqiu’had the highest maximum net photosynthetic rate(P n,max)and the lowest dark respiration rate(R d),along with the highest chlorophyll content.It indicated that‘Yanqiu’has strong photosynthetic capacity and organic matter accumulation ability.It also had the highest P LSP,enabling it to fully utilize the high light environment of the Yanshan Mountains and possessed high light efficiency characteristics.The P n,max of‘Yanqiu’was significantly higher than other varieties.‘Hybrid 22’and‘Yanbao’also exhibited significantly higher P n,max compared with‘Yanjia’and‘Qianxi 37’.‘Yanchang’had the lowest P n,max.The order of P n,max among the six chestnut varieties or strains was as follows:‘Yanqiu’>‘Hybrid 22’>‘Yanbao’>‘Yanjia’>‘Qianxi 37’>‘Yanchang’.[Conclusions] 展开更多
关键词 Chinese chestnut Diurnal variation of photosynthesis Light response model Light response curve CHLOROPHYLL
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Study on the Efficacy of Shugan Jieyu Capsules Combined with Trazodone in Patients with Post-Stroke Depression and Insomnia
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作者 Tie Mao yong yang +6 位作者 Xi Chen Ping Liu Peng Zhang Chunju Wu Xiaojun Hou Cuicui Rong Jujun Xue 《Journal of Clinical and Nursing Research》 2024年第2期50-55,共6页
Objective:To analyze the effectiveness of applying ShuGan JieYu Capsules(SGJYC)combined with trazodone in patients with post-stroke depression(PSD)with insomnia.Methods:60 cases of PSD with insomnia patients admitted ... Objective:To analyze the effectiveness of applying ShuGan JieYu Capsules(SGJYC)combined with trazodone in patients with post-stroke depression(PSD)with insomnia.Methods:60 cases of PSD with insomnia patients admitted to the hospital from May 2022 to May 2023 were selected and randomly divided into a reference group(trazodone)and a research group(SGJYC combined with trazodone)of 30 cases each.Statistics were analyzed using the Hamilton Depression Rating Scale(HAM-D),Pittsburgh Sleep Quality Index(PSQI),and Activities of Daily Living(ADL)scale before treatment and 4,8,and 12 weeks after treatment.Results:Before treatment,The results of HAM-D,PSQI,and ADL scale studies in the two groups before treatment were not statistically significant(P>0.05);4,8,and 12 weeks after treatment,the results of HAM-D and PSQI studies in the research group were lower than that of the reference group,and the results of ADL scale studies were higher than that of the reference group.There was a significant difference between the groups(P<0.05).The total adverse reaction rate of the research group was lower than that of the reference group,and there was a significant difference between the groups(P<0.05).Conclusion:The combination of SGJYC and trazodone reduced depression in post-stroke patients,corrected insomnia,improved sleep quality,was safe,and had a low rate of adverse reactions. 展开更多
关键词 ShuGan JieYu Capsules Trazodone STROKE DEPRESSION INSOMNIA
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Reform of the Comprehensive Practical Course System for Mechanical and Electronic Engineering Majors Under the Background of New Engineering
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作者 Yali Yu Keyi Wang yong yang 《Journal of Contemporary Educational Research》 2024年第2期85-90,共6页
Under the background of new engineering,the reform of the comprehensive practical course system for mechanical and electronic engineering majors actively responds to the challenges posed by the new round of technologi... Under the background of new engineering,the reform of the comprehensive practical course system for mechanical and electronic engineering majors actively responds to the challenges posed by the new round of technological revolution and industrial transformation to higher education,cultivating top-notch innovative intellectuals with comprehensive engineering qualities,meeting the requirements of being able to solve complex engineering problems rather than just cognitive capabilities,forming two core courses through reconstructing and reshaping the core courses of the major.The core courses include Drive,Measurement,and Control I and Drive,Measurement,and Control II,which highlight the comprehensive framework of mechanical and electronic engineering professional knowledge,continuing the comprehensive practical course system based on the unity of knowledge and practice,following the trend of new engineering,highlighting the practicality of professional innovation,assisting engineering education reform,and promoting high-quality development of new engineering professionals cultivation. 展开更多
关键词 Comprehensive engineering quality Mechanical and Electronic Engineering Practical course system New engineering
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Construction and Weight Distributions of Binary Linear Codes Based on Deep Holes
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作者 yong yang Wenwei Qiu 《Applied Mathematics》 2023年第10期684-695,共12页
Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, ... Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, we consider constructing binary linear codes by combining deep holes with binary BCH codes. In this article, we consider the 2-error-correcting binary primitive BCH codes and the extended codes to construct new binary linear codes by combining them with deep holes, respectively. Furthermore, three classes of binary linear codes are constructed, and then we determine the parameters and the weight distributions of these new binary linear codes. 展开更多
关键词 Linear Codes MacWilliams Equations Weight Distribution Dual Codes Deep Holes Covering Radius
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超声振动对不同含量碳纤维增强聚丙烯制件性能的影响
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作者 刘莹 杨勇 +3 位作者 于同敏 赵雪利 马赛 祝铁丽 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第12期80-87,共8页
利用超声辅助振动注塑模具,针对3种不同质量分数(10%,15%和20%)的碳纤维增强聚丙烯(CFPP)复合材料,进行了底部带有标准拉伸试样的壳体制件的成型实验。借助X射线衍射、扫描电镜等观测分析及拉伸性能测试,研究了超声振动外场作用下,不同... 利用超声辅助振动注塑模具,针对3种不同质量分数(10%,15%和20%)的碳纤维增强聚丙烯(CFPP)复合材料,进行了底部带有标准拉伸试样的壳体制件的成型实验。借助X射线衍射、扫描电镜等观测分析及拉伸性能测试,研究了超声振动外场作用下,不同碳纤维含量的制件内部结晶度及凝聚态结构中碳纤维的空间形态,以及碳纤维与基体接触界面的结合强度对制件力学性能的影响。结果表明,在CFPP制件注塑成型的填充流动阶段施加600W功率的超声振动,上述不同碳纤维含量的制件结晶度分别提高了4.4%,7.4%和9.8%,纤维取向程度分别提高了5.2%,9.7%和3.5%,纤维与基体的结合强度分别提高了32.5%,12.7%和12.6%,最终使得制件的拉伸强度相比于未施加超声振动时分别提高了6.9%,6.2%和10.4%;但超声功率高达到900W时,结晶度和纤维与基体的结合强度有所下降,导致制件拉伸强度有所降低。 展开更多
关键词 超声振动 碳纤维增强聚丙烯 凝聚态结构 拉伸强度
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一类(1+1)维变系数复方程的可积性研究 被引量:1
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作者 张金玉 王丹 +2 位作者 耿勇 杨苗苗 王晓丽 《数学物理学报(A辑)》 CSCD 北大核心 2023年第4期994-1002,共9页
该文基于双Bell多项式与Hirota双线性算子之间的关系,研究了一类(1+1)维变系数复方程的可积性.首先通过适当的变换,构造出方程的双线性表达式、双线性Backlund变换,又通过Hopf-Cole变换得到方程的Lax对,从而证明该方程具有Lax可积性.
关键词 (1+1)维变系数复方程 BELL多项式 Hirota双线性形式 BACKLUND变换 LAX对
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具有高效激子解离和明确反应位点的Tröger碱基三维多孔芳基有机骨架及其光催化近单一选择性CO_(2)转化
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作者 殷楠 陈伟斌 +8 位作者 杨勇 唐钲 李攀杰 张潇月 唐兰勤 王天宇 王阳 周勇 邹志刚 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第8期168-179,共12页
植物光合作用是吸收光能,把CO_(2)和水转化成富能有机物,同时释放氧气的过程.受此启发,利用太阳光将CO_(2)转化为碳氢燃料的人工碳中和技术引起了广泛关注.人工光合作用能否成功实施取决于光催化剂的设计制备.无机半导体已被广泛研究用... 植物光合作用是吸收光能,把CO_(2)和水转化成富能有机物,同时释放氧气的过程.受此启发,利用太阳光将CO_(2)转化为碳氢燃料的人工碳中和技术引起了广泛关注.人工光合作用能否成功实施取决于光催化剂的设计制备.无机半导体已被广泛研究用于CO_(2)光还原反应(CO_(2)PRR),但其存在金属氧化物的带隙较宽且难以调节、导致光吸收较差和金属硫化物的光腐蚀问题严重等明显的缺点.此外,高载流子复合率和低比表面积会影响光催化效率,从而限制光子利用.因此,基于有机聚合物的无金属催化剂因其突出的可设计调控性而被提出,其中,具有超高比表面积的材料—多孔芳香骨架(PAFs)聚合物是研究热点之一,但是传统PAFs材料多为二维平面结构,用于光催化的无金属三维PAFs报道较少.此外,具有孤对电子的杂原子(N,B,F)修饰的材料可以与CO_(2)分子产生特定的偶极-四极相互作用,提高材料对CO_(2)的吸附和活化能力,是提升有机聚合物光催化剂性能的有效策略.本文采用Sonogashira-Hagihara偶联将具有不同共轭程度的芳香炔烃(2,2’,7,7‘-四乙炔基-9,9’-螺二芴,SPF-T;四(4-乙炔基苯基)甲烷,TEPM-T;1,1,2,2-四(4-乙炔基苯基)乙烯,TEPE-T)与含有N杂原子的Tröger碱聚合制备了具有三维结构的多孔芳香骨架聚合物X-TB-PAFs(X=TEPE,TEPM,SPF).通过X-射线衍射、红外光谱、13C核磁共振(NMR)以及1H NMR等表征手段验证了目标聚合物的成功合成.通过紫外-可见光谱和Mott-Schottky曲线测试研究了聚合物具体的能带结构,发现三种PAFs聚合物材料在热力学上同时满足光催化CO_(2)-CO的还原反应条件(Eθ=-0.51 Vvs.NHE,pH=7)和光催化H2O-O_(2)的氧化条件(Eθ=0.82 V vs.NHE,pH=7).V形骨架结构的Tröger碱(TB)单元和芳炔的结合赋予了聚合物刚性稳定的孔隙率以及较高的比表面积,材料中的多孔结构可以使其暴露更多的活性位点,三维框架结构为反应物接近活性位点提供了丰富的开放式空腔,这些都有利于材料对CO_(2)的捕获,增强催化剂对CO_(2)的吸附/活化能力.此外,炔基充当连接通道还可以增强体系的载流子迁移率,提升材料的光催化性能.密度泛函理论计算和光电性能测试结果表明,TB官能团引入带来的分子内极化和电子陷阱位点的优势,其与三维共轭网络结构一起协同调节了光生载流子的分离和反应位点分布.三种三维PAFs中,基于全共轭结构TEPE-T的TEPE-TB-PAF表现出最高效的光生载流子传输与分离效率,在没有助催化剂和牺牲剂的情况下表现出较好的光催化CO产率(194.50μmolg^(-1)h^(-1))和近乎单一的选择性(99.74%).全共轭TEPE-T的引入和分子内极化的存在可以促进框架内载流子的分离和迁移.材料中的电偶极矩(从负电荷到正电荷)指向TB中含有叔氮官能团的桥接位点,使其成为明确的催化反应位点.光电流和阻抗测试结果表明,TEPE-TB-PAF具有更好的电子-空穴分离能力和更小的电荷迁移位阻.三维框架构建产生的多重散射截面可以促进材料中的光子吸收,从而提高其光催化性能.理论计算和原位漫反射傅立叶变换红外光谱结果表明,材料中CO解吸的低能垒和*CHO形成的高能垒是TEPE-TB-PAF高CO产率和选择性的根本机制.综上,本文为多功能高效有机聚合物光催化剂的合成提供了有效途径,并为同时改善光催化剂的转化率和选择性提供了借鉴. 展开更多
关键词 CO_(2)光还原 多孔芳香骨架 Tröger碱 三维网络 分子内极化
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Quercetin-derivatives painting the yellow petals of American lotus(Nelumbo lutea)and enzymatic basis for their accumulation 被引量:1
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作者 Qingqing Liu Dasheng Zhang +7 位作者 Fengluan Liu Zhuoxing Liu Xiaohan Wang yong yang Shanshan Li Hanchun Li Daike Tian Liangsheng Wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第1期169-182,共14页
American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide... American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide to be the dominant pigment.The variation tendency of the total flavonol content was coincident with yellow color variation of petals during flower development.To understand the mechanism of accumulation and constituent of pigments in petals,three pivotal genes,NlFLS1,NlFLS2 and NlFLS3,which were predicted to encode flavonol synthases were isolated and characterized by analyses of basic bioinformatics,temporal and spatial expression patterns and enzymatic activity.Their temporal expression levels showed the same variation tendency,which was also consistent with the development-dependent variation of total flavonol content.Spatial expression patterns indicated the three genes should function in petals.All the three proteins were demonstrated to be bifunctional dioxygenase,possessing both flavonol synthase activity and flavanone 3-hydroxylase activity.Besides,other flavonol biosynthesis related genes were also investigated on their expression levels to give more clues on the mechanism.Substrate preferences of the three FLSs,substrate competitions between the FLSs and other flavonol biosynthesis related enzymes,and the greatly differential expression levels between F3’H(flavonoid 3-hydroxylase)and F3’5’H(flavonoid 3,5-hydroxylase)contributed to the flavonol constituent in the petals of America lotus,namely abundant quercetin-derivatives while very few kaempferol-derivatives and myricetin-derivatives. 展开更多
关键词 LOTUS NELUMBO Flavonoid FLAVONOL QUERCETIN
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A self-powered ultraviolet photodetector based on a Ga_(2)O_(3)/Bi_(2)WO_(6)heterojunction with low noise and stable photoresponse 被引量:1
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作者 杨莉莉 彭宇思 +4 位作者 刘增 张茂林 郭宇锋 杨勇 唐为华 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期605-612,共8页
A self-powered solar-blind ultraviolet(UV)photodetector(PD)was successfully constructed on a Ga_(2)O_(3)/Bi_(2)WO_(6)heterojunction,which was fabricated by spin-coating the hydrothermally grown Bi_(2)WO_(6)onto MOCVD-... A self-powered solar-blind ultraviolet(UV)photodetector(PD)was successfully constructed on a Ga_(2)O_(3)/Bi_(2)WO_(6)heterojunction,which was fabricated by spin-coating the hydrothermally grown Bi_(2)WO_(6)onto MOCVD-grown Ga_(2)O_(3)film.The results show that a typical type-I heterojunction is formed at the interface of the Ga_(2)O_(3)film and clustered Bi_(2)WO_(6),which demonstrates a distinct photovoltaic effect with an open-circuit voltage of 0.18 V under the irradiation of 254 nm UV light.Moreover,the Ga_(2)O_(3)/Bi_(2)WO_(6)PD displays excellent photodetection performance with an ultra-low dark current of~6 fA,and a high light-to-dark current ratio(PDCR)of 3.5 x 10^(4)in self-powered mode(0 V),as well as a best responsivity result of 2.21 mA/W in power supply mode(5 V).Furthermore,the PD possesses a stable and fast response speed under different light intensities and voltages.At zero voltage,the PD exhibits a fast rise time of 132 ms and 162 ms,as well as a quick decay time of 69 ms and 522 ms,respectively.In general,the newly attempted Ga_(2)O_(3)/Bi_(2)WO_(6)heterojunction may become a potential candidate for the realization of self-powered and high-performance UV photodetectors. 展开更多
关键词 Ga_(2)O_(3)/Bi_(2)WO_(6)heterojunction UV photodetector self-powered operation
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Biogenesis of flavor-related linalool is diverged and genetically conserved in tree peony (Paeonia × suffruticosa) 被引量:1
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作者 Shanshan Li Ling Zhang +4 位作者 Miao Sun Mengwen Lv yong yang Wenzhong Xu Liangsheng Wang 《Horticulture Research》 SCIE CSCD 2023年第2期15-27,共13页
Floral scent is an important and genetically complex trait in horticultural plants.Tree peony(Paeonia×suffruticosa)originates in the Pan-Himalaya and has nine wild species divided into two subsections,Delavayanae... Floral scent is an important and genetically complex trait in horticultural plants.Tree peony(Paeonia×suffruticosa)originates in the Pan-Himalaya and has nine wild species divided into two subsections,Delavayanae and Vaginatae.Their f lowers are beloved worldwide for their sweet f loral fragrance,yet the f lavor-related volatiles and underlying biosynthetic pathways remain unknown.Here,we characterized the volatile blends of all wild tree peony species and found that the flavor-related volatiles were highly divergent,but linalool was a unique monoterpene in subsect.Delavayanae.Further detection of volatiles in 97 cultivars with various genetic backgrounds showed that linalool was also the characteristic aroma component in Paeonia delavayi hybrid progenies,suggesting that linalool was conserved and dominant within subsect.Delavayanae and its hybrids,instead of species and cultivars from subsect.Vaginatae.Global transcriptome analysis of all wild tree peony species and 60 cultivars revealed five candidate genes that may be involved in key steps of linalool biosynthesis;especially the expressions of three TPS genes,PdTPS1,PdTPS2,and PdTPS4,were significantly positively correlated with linalool emissions across tree peony cultivars.Further biochemical evidence demonstrated that PdTPS1 and PdTPS4were the pivotal genes determining the species-specific and cultivar-specific emission of linalool.This study revealed a new insight into floral scent divergence in tree peony and would greatly facilitate our understanding of the phylogeny and evolution of Paeonia. 展开更多
关键词 CONSERVED tree STEPS
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Full-chain enhanced ion transport toward stable lithium metal anodes
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作者 Yuliang Gao Fahong Qiao +7 位作者 Nan Li Jingyuan You yong yang Jun Wang Chao Shen Ting Jin Xi Li Keyu Xie 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期390-397,共8页
The dendrite growth that results from the slow electrode process kinetics prevents the lithium(Li) metal anode from being used in practical applications. Here, full-chain enhanced ion transport for stabilizing Li meta... The dendrite growth that results from the slow electrode process kinetics prevents the lithium(Li) metal anode from being used in practical applications. Here, full-chain enhanced ion transport for stabilizing Li metal anodes is proposed. Experimental and theoretical studies confirm that full-chain enhanced ion transport(electrocrystallization, mass transport in the electrolyte and diffusion in solid electrolyte interphase) under magnetoelectrochemistry contributes to a homogeneous, dense, and dendrite-free morphology. Specifically, the enhanced electrocrystallization behavior promotes the Li nucleation;the enhanced mass transport in the electrolyte alleviates the ion concentration gradient at the electrode surface, which helps to inhibit dendrite growth;and the enhanced diffusion in the solid electrolyte interphase further homogenizes the Li deposition behavior, obtaining regular and uniform Li particles.Consequently, the Li metal anode has exceptional cycling stability in both symmetric and full cells,and the pouch cell performs long cycles(170 cycles) in practice evaluation. This work advances fundamental knowledge of the magneto-dendrite effect and offers a new perspective on stabilizing metal anodes. 展开更多
关键词 Lithium metal anodes Ion transport Pouch cell Lithium dendrites Magnetic field
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Multi-point discharge model: study on corona discharge of double-ended needle in large space
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作者 李丁晨 李家玮 +5 位作者 李传 张明 王鹏宇 刘志 杨勇 于克训 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第3期62-69,共8页
Corona discharge, as a common means to obtain non-equilibrium plasma, can generally obtain high-concentration plasma by increasing discharge points to meet production needs. However,the existing numerical simulation m... Corona discharge, as a common means to obtain non-equilibrium plasma, can generally obtain high-concentration plasma by increasing discharge points to meet production needs. However,the existing numerical simulation models used to study multi-point corona discharge are all calculations of small-scale space models, which cannot obtain the distribution characteristics of plasma in large space. Based on our previous research, this paper proposes a hybrid model for studying the distribution of multi-point discharge plasma in large-scale spaces, which divides the computational domain and computes separately with the hydrodynamic model and the ion mobility model. The simulation results are verified by a needle–ball electrode device. Firstly, the electric field distribution and plasma distribution of the needle electrodes with single tip and double tips are compared and discussed. Secondly, the plasma distribution of the needle electrode with the double tip at different voltages is investigated. Both computational and experimental results indicate that the charged particle concentration and current of the needle electrode with double tips are both twice as high as those of the needle electrode with a single tip. This model can extend the computational area of the multi-point corona discharge finite element model to the sub-meter(25 cm) or meter level, which provides an effective means to study the plasma distribution generated by multiple discharge points in large-scale space. 展开更多
关键词 corona discharge numerical simulation multi-point discharge large space double needle tip electrode
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