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Research Progress and Prospects for the Evolution Process and Treatment Technology of Urban Black and Smelly Water
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作者 Zhuolin LI weijie xu 《Meteorological and Environmental Research》 CAS 2023年第1期68-69,75,共3页
Water is an important material resource for human survival,and with the increasing development of society,the amount of urban industrial wastewater and domestic sewage is gradually increasing.However,wastewater collec... Water is an important material resource for human survival,and with the increasing development of society,the amount of urban industrial wastewater and domestic sewage is gradually increasing.However,wastewater collection and treatment facilities lag behind,so that a large number of wastewater enters urban water,making urban water become gradually black and smelly.In order to provide a good living environment for human beings,a large number of scholars actively explore the treatment technology of black and smelly water.In this paper,the evolution process of black and smelly water was introduced firstly,and then the treatment technology of black and smelly water was summarized.Finally,the prospects for the development of the treatment technology were put forward. 展开更多
关键词 Black and smelly water Evolution process Treatment technology Research progress PROSPECTS
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具有沉积结构环氧树脂电磁屏蔽材料的制备及表征 被引量:2
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作者 廉青松 李言 +4 位作者 徐伟杰 陈宏峰 赵贵哲 刘亚青 程珏 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第2期66-72,共7页
文中首先构筑具有三维结构的四针状氧化锌负载银(Ag@T-ZnO)和二维石墨烯纳米片(GNS)的混杂导电网络,随后灌注环氧树脂固化得到具有沉积结构的Ag@T-ZnO/GNS/EP复合材料,系统研究了Ag@T-ZnO和GNS的配比对复合材料屏蔽效能和力学性能的影... 文中首先构筑具有三维结构的四针状氧化锌负载银(Ag@T-ZnO)和二维石墨烯纳米片(GNS)的混杂导电网络,随后灌注环氧树脂固化得到具有沉积结构的Ag@T-ZnO/GNS/EP复合材料,系统研究了Ag@T-ZnO和GNS的配比对复合材料屏蔽效能和力学性能的影响。当Ag@T-ZnO和GNS总质量分数为复合材料的20%且二者质量比为9:1时,二者之间的协同作用及独特的沉积导电网络结构赋予了复合材料优异的屏蔽效能和力学性能,在X波段的平均屏蔽效能可以达到83.8 dB,拉伸性能可达到51.6 MPa。为设计制备兼具优异力学性能和屏蔽性能的复合材料提供了新的思路。 展开更多
关键词 力学性能 电磁屏蔽 四针状氧化锌负载银 石墨烯纳米片 环氧树脂 沉积结构
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Advances in phase-sensitive optical time-domain reflectometry 被引量:12
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作者 Shuaiqi Liu Feihong Yu +3 位作者 Rui Hong weijie xu Liyang Shao Feng Wang 《Opto-Electronic Advances》 SCIE EI 2022年第3期25-52,I0001,共29页
Phase-sensitive optical time-domain reflectometry(Φ-OTDR)has attracted numerous attention due to its superior performance in detecting the weak perturbations along the fiber.Relying on the ultra-sensitivity of light ... Phase-sensitive optical time-domain reflectometry(Φ-OTDR)has attracted numerous attention due to its superior performance in detecting the weak perturbations along the fiber.Relying on the ultra-sensitivity of light phase to the tiny deformation of optical fiber,Φ-OTDR has been treated as a powerful technique with a wide range of applications.It is fundamental to extract the phase of scattering light wave accurately and the methods include coherent detection,I/Q demodulation,3 by 3 coupler,dual probe pulses,and so on.Meanwhile,researchers have also made great efforts to improve the performance ofΦ-OTDR.The frequency response range,the measurement accuracy,the sensing distance,the spatial resolution,and the accuracy of event discrimination,all have been enhanced by various techniques.Furthermore,lots of researches on the applications in various kinds of fields have been carried out,where certain modifications and techniques have been developed.Therefore,Φ-OTDR remains as a booming technique in both researches and applications. 展开更多
关键词 optical fiber sensors Ф-OTDR phase demodulation application research
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Analysis of actuator delay and its effect on uncertainty quantification for real-time hybrid simulation 被引量:2
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作者 Cheng Chen weijie xu +1 位作者 Tong Guo Kai Chen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第4期713-725,共13页
Uncertainties in structure properties can result in different responses in hybrid simulations. Quantification of the effect of these tmcertainties would enable researchers to estimate the variances of structural respo... Uncertainties in structure properties can result in different responses in hybrid simulations. Quantification of the effect of these tmcertainties would enable researchers to estimate the variances of structural responses observed from experiments. This poses challenges for real-time hybrid simulation (RTHS) due to the existence of actuator delay. Polynomial chaos expansion (PCE) projects the model outputs on a basis of orthogonal stochastic polynomials to account for influences of model uncertainties. In this paper, PCE is utilized to evaluate effect of actuator delay on the maximum displacement from real-time hybrid simulation of a single degree of freedom (SDOF) structure when accounting for uncertainties in structural properties. The PCE is first applied for RTHS without delay to determine the order of PCE, the number of sample points as well as the method for coefficients calculation. The PCE is then applied to RTHS with actuator delay. The mean, variance and Sobol indices are compared and discussed to evaluate the effects of actuator delay on uncertainty quantification for RTHS. Results show that the mean and the variance of the maximum displacement increase linearly and exponentially with respect to actuator delay, respectively. Sensitivity analysis through Sobol indices also indicates the influence of the single random variable decreases while the coupling effect increases with the increase of actuator delay. 展开更多
关键词 real-time hybrid simulation actuator delay polynomial chaos expansion delay differential equation uncertainty quantification
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Effect of Dietary Vitamin C on the Antioxidant Defense System of Hibernating Juvenile Three-keeled Pond Turtles (Chinemys reevesii)
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作者 Qi ZHANG Cuijuan NIU weijie xu 《Asian Herpetological Research》 SCIE 2012年第2期151-156,共6页
Juvenile three-keeled pond turtles(Chinemys reevesii) were fed diets supplemented with vitamin C(Vc) at doses of 0(basal diet, Vc0), 100(Vc100), 200(Vc200), 500(Vc500) and 2500(Vc2500) mg/kg diets at 28°C for 4 w... Juvenile three-keeled pond turtles(Chinemys reevesii) were fed diets supplemented with vitamin C(Vc) at doses of 0(basal diet, Vc0), 100(Vc100), 200(Vc200), 500(Vc500) and 2500(Vc2500) mg/kg diets at 28°C for 4 weeks, respectively. Then, the water temperature was gradually reduced to 10°C, and the turtles were induced into hibernation. Liver tissue samples were collected at three time points: start of hibernation(T1), 4 and 6 weeks’ hibernation(T2 and T3). A control group fed with the basal diet was set to parallel the whole treatment process, but reared at 28°C constantly. The results showed that hibernation mildly affected the antioxidant system and the influence varied with hibernating time. Hepatic malondialdehyde content of the Vc100 group was significantly lower than that of the other groups at T1. At T2, hepatic MDA in the groups of Vc500 and Vc2500 decreased significantly, while no clear differences were found among all groups at T3. The activities of antioxidant enzymes showed a positive correlation with dietary Vc dose before hibernation. After hibernation, total antioxidant capability was not affected by Vc. Superoxide dismutase activity became similar in different groups at T2, but decreased in higher Vc groups(≥ 200 mg/kg) at T3. Glutathione peroxidase and glutathione-S-transferase activities decreased significantly with dietary Vc supplementation(≥ 100 mg/kg) at T2, but recovered at T3. The result indicates that under normal rearing condition, low dietary Vc supplementation(< 100 mg/kg) might be beneficial to the antioxidant defense system. The effect of dietary Vc on the antioxidant defense system differed during hibernation. 展开更多
关键词 Chinemys reevesii HIBERNATION vitamin C antioxidant capability
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A transcriptional cascade mediated by two APETALA2 family members orchestrates carotenoid biosynthesis in tomato 被引量:1
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作者 Xiaoqing He Kaidong Liu +6 位作者 Yi Wu weijie xu Ruochen Wang Julien Pirrello Mondher Bouzayen Mengbo Wu Mingchun Liu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2024年第6期1227-1241,共15页
Carotenoids are important nutrients for human health that must be obtained from plants since they cannot be biosynthesized by the human body.Dissecting the regulatory mechanism of carotenoid metabolism in plants repre... Carotenoids are important nutrients for human health that must be obtained from plants since they cannot be biosynthesized by the human body.Dissecting the regulatory mechanism of carotenoid metabolism in plants represents the first step toward manipulating carotenoid contents in plants by molecular design breeding.In this study,we determined that SlAP2c,an APETALA2(AP2)family member,acts as a transcriptional repressor to regulate carotenoid biosynthesis in tomato(Solanum lycopersicum).Knockout of SlAP2c in both the“Micro Tom”and“Ailsa Craig”backgrounds resulted in greater lycopene accumulation,whereas overexpression of this gene led to orange-ripe fruit with significantly lower lycopene contents than the wild type.We established that SlAP2c represses the expression of genes involved in lycopene biosynthesis by directly binding to the cis-elements in their promoters.Moreover,SlAP2c relies on its EAR motif to recruit the co-repressors TOPLESS(TPL)2/4 and forms a complex with histone deacetylase(had)1/3,thereby reducing the histone acetylation levels of lycopene biosynthesis genes.Furthermore,SlAP2a,a homolog of SlAP2c,acts upstream of SlAP2c and alleviates the SlAP2c-induced repression of lycopene biosynthesis genes by inhibiting SlAP2c transcription during fruit ripening.Therefore,we identified a transcriptional cascade mediated by AP2 family members that regulates lycopene biosynthesis during fruit ripening in tomato,laying the foundation for the manipulation of carotenoid metabolism in plants. 展开更多
关键词 APETALA2 family members carotenoid biosynthesis TOMATO transcriptional cascade
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肺动脉高压右心重构中心肌细胞的细胞死亡途径:探索重塑之路
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作者 王尚 徐唯傑 +5 位作者 何雯妮 胡肖依 屈奕阳 刘雨杨 颜艺 姜蓉 《科学通报》 EI CAS CSCD 北大核心 2024年第13期1725-1741,共17页
细胞死亡对于机体生长、发育和调节稳态非常关键,是心脏病理学中的一个基本过程.证据表明,在各种心血管系统疾病中,细胞凋亡、坏死性凋亡、线粒体通透性改变驱动的坏死、焦亡、铁死亡以及自噬等死亡方式在心脏重构、心力衰竭过程中起着... 细胞死亡对于机体生长、发育和调节稳态非常关键,是心脏病理学中的一个基本过程.证据表明,在各种心血管系统疾病中,细胞凋亡、坏死性凋亡、线粒体通透性改变驱动的坏死、焦亡、铁死亡以及自噬等死亡方式在心脏重构、心力衰竭过程中起着重要作用.随着肺动脉高压的进展,右心室发生失代偿性肥大,最终导致心室衰竭并伴随着心肌细胞死亡.因此,探讨此过程中心肌细胞死亡的具体机制对于改善患者预后意义重大.本文综述了各种心肌细胞死亡方式的信号通路和各种细胞死亡方式的检测、评估方法,总结了肺动脉高压中心肌细胞死亡方式的有关研究现况,讨论了针对不同细胞死亡方式研究对于肺动脉高压靶向治疗的研究前景. 展开更多
关键词 肺动脉高压 凋亡 坏死性凋亡 线粒体通透性改变驱动的坏死 焦亡 铁死亡
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基于宏病毒组学技术挖掘猪腹泻粪便的病毒群落组成
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作者 陶洁 李本强 +5 位作者 程靖华 石迎 刘佩红 何桂霞 徐伟杰 刘惠莉 《生物多样性》 CAS CSCD 北大核心 2023年第11期131-139,共9页
为系统鉴定现阶段上海地区仔猪腹泻样品中的病毒群落组成,本研究利用宏病毒组学技术对临床采集的猪腹泻粪便进行了宏病毒高通量测序。结果显示,测序获得了1,676,726个RNAcontig和95,111个DNAcontig,RNA病毒和DNA病毒序列分别占比38.58%... 为系统鉴定现阶段上海地区仔猪腹泻样品中的病毒群落组成,本研究利用宏病毒组学技术对临床采集的猪腹泻粪便进行了宏病毒高通量测序。结果显示,测序获得了1,676,726个RNAcontig和95,111个DNAcontig,RNA病毒和DNA病毒序列分别占比38.58%和3.10%。其中星状病毒科、杯状病毒科和小RNA病毒科是病毒总群落中占比最高的前3个科。虽然DNA病毒在病毒总群落中的占比较低,但其单组分环状DNA(CRESS-DNA)病毒种类丰富多样,包含有18种CRESS-DNA病毒。经基因组序列深度拼接,共获得了46条病毒全基因组序列,包括2株猪星状病毒和3株类似星状病毒、2株札幌病毒、16株小双节RNA病毒和23株CRESS-DNA病毒。其中1株札幌病毒归属于GII/3亚型,与人札幌病毒亲缘性较近。16株小双节RNA病毒中有4株归属于GGI亚型,其余12株归属于GGII亚型。23株CRESS-DNA病毒中有1株归属于类双生病毒科、12株CRESS-DNA病毒归属于小环状DNA病毒科,另外10株CRESS-DNA病毒未分类。本研究揭示现阶段猪腹泻粪便中以RNA病毒为主导,且存在宿主多样性,提示可能存在种间基因重组,病原潜在危害性需进一步挖掘和验证。研究数据将为临床猪腹泻病防控提供参考和借鉴。 展开更多
关键词 仔猪腹泻病 宏病毒组学 病毒群落 全基因组序列
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Artificial Intelligence for Edge Service Optimization in Internet of Vehicles:A Survey 被引量:13
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作者 Xiaolong xu Haoyuan Li +3 位作者 weijie xu Zhongjian Liu Liang Yao Fei Dai 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2022年第2期270-287,共18页
The Internet of Vehicles(IoV)plays a crucial role in providing diversified services because of its powerful capability of collecting real-time information.Generally,collected information is transmitted to a centralize... The Internet of Vehicles(IoV)plays a crucial role in providing diversified services because of its powerful capability of collecting real-time information.Generally,collected information is transmitted to a centralized resourceintensive cloud platform for service implementation.Edge Computing(EC)that deploys physical resources near road-side units is involved in IoV to support real-time services for vehicular users.Additionally,many measures are adopted to optimize the performance of EC-enabled IoV,but they hardly help make dynamic decisions according to real-time requests.Artificial Intelligence(AI)is capable of enhancing the learning capacity of edge devices and thus assists in allocating resources dynamically.Although extensive research has employed AI to optimize EC performance,summaries with relative concepts or prospects are quite few.To address this gap,we conduct an exhaustive survey about utilizing AI in edge service optimization in IoV.Firstly,we establish the general condition and relative concepts about IoV,EC,and AI.Secondly,we review the edge service frameworks for IoV and explore the use of AI in edge server placement and service offloading.Finally,we discuss a number of open issues in optimizing edge services with AI. 展开更多
关键词 edge service internet of vehicles artificial intel igence
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