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Early identification of stroke through deep learning with multi-modal human speech and movement data
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作者 Zijun Ou haitao wang +9 位作者 Bin Zhang Haobang Liang Bei Hu Longlong Ren Yanjuan Liu Yuhu Zhang Chengbo Dai Hejun Wu Weifeng Li Xin Li 《Neural Regeneration Research》 SCIE CAS 2025年第1期234-241,共8页
Early identification and treatment of stroke can greatly improve patient outcomes and quality of life.Although clinical tests such as the Cincinnati Pre-hospital Stroke Scale(CPSS)and the Face Arm Speech Test(FAST)are... Early identification and treatment of stroke can greatly improve patient outcomes and quality of life.Although clinical tests such as the Cincinnati Pre-hospital Stroke Scale(CPSS)and the Face Arm Speech Test(FAST)are commonly used for stroke screening,accurate administration is dependent on specialized training.In this study,we proposed a novel multimodal deep learning approach,based on the FAST,for assessing suspected stroke patients exhibiting symptoms such as limb weakness,facial paresis,and speech disorders in acute settings.We collected a dataset comprising videos and audio recordings of emergency room patients performing designated limb movements,facial expressions,and speech tests based on the FAST.We compared the constructed deep learning model,which was designed to process multi-modal datasets,with six prior models that achieved good action classification performance,including the I3D,SlowFast,X3D,TPN,TimeSformer,and MViT.We found that the findings of our deep learning model had a higher clinical value compared with the other approaches.Moreover,the multi-modal model outperformed its single-module variants,highlighting the benefit of utilizing multiple types of patient data,such as action videos and speech audio.These results indicate that a multi-modal deep learning model combined with the FAST could greatly improve the accuracy and sensitivity of early stroke identification of stroke,thus providing a practical and powerful tool for assessing stroke patients in an emergency clinical setting. 展开更多
关键词 artificial intelligence deep learning DIAGNOSIS early detection FAST SCREENING STROKE
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CoP修饰Ti_(3)C_(2)T_(x)MXene纳米复合材料作为高效析氢反应电催化剂 被引量:1
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作者 孙巍 王永靖 +5 位作者 项坤 白赛帅 王海涛 邹菁 Arramel 江吉周 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第8期36-39,共4页
高效、经济和环保是电化学水分解制氢电催化剂的关键要素。二维(2D)MXene材料因其独特的物理化学性质而受到广泛关注。虽然有许多不同种类的MXene材料,但只有少数具有本征析氢反应(HER)催化活性。然而,MXene材料具有很多优点,如较大的... 高效、经济和环保是电化学水分解制氢电催化剂的关键要素。二维(2D)MXene材料因其独特的物理化学性质而受到广泛关注。虽然有许多不同种类的MXene材料,但只有少数具有本征析氢反应(HER)催化活性。然而,MXene材料具有很多优点,如较大的比表面积、高电导率和丰富的表面官能团,因此可以作为与其他物质复合的理想平台。本研究首先通过密度泛函理论(DFT)预测了CoP与Ti_(3)C_(2)T_(x)MXene(其中T_(x)=―F和―OH官能团)具有低的氢吸附自由能(ΔGH^(*))。接着,我们合成了CoP-Ti_(3)C_(2)T_(x)MXene纳米复合材料,并在0.5 mol∙L^(−1)H_(2)SO_(4)中测试了其电催化HER性能。该材料在电流密度为10 mA∙cm^(−2)时表现出了低的过电位(135 mV)和Tafel斜率为48 mV∙dec^(−1)。理论计算表明,CoP-Ti_(3)C_(2)T_(x)MXene纳米复合材料的优异电催化性能源于Ti_(3)C_(2)T_(x)的高金属导电性、良好的界面电荷转移、快速的氢吸附/解吸过程以及优化的电子结构。 展开更多
关键词 Ti_(3)C_(2)T_(x)MXene 析氢反应 COP 密度泛函理论 界面电荷转移
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硫取代氮增强g-C_(3)N_(4)光催化产氢性能 被引量:2
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作者 王海涛 余良浪 +2 位作者 江吉周 Arramel 邹菁 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第5期41-44,共4页
利用取之不尽的太阳能资源进行光催化水裂解制氢是缓解全球能源危机、实现碳中和战略的一项有前景的技术。石墨相氮化碳(g-C_(3)N_(4))因成本低且稳定性高在光催化产氢领域备受关注。然而,纯g-C_(3)N_(4)存在表面积小、电子转移慢、光... 利用取之不尽的太阳能资源进行光催化水裂解制氢是缓解全球能源危机、实现碳中和战略的一项有前景的技术。石墨相氮化碳(g-C_(3)N_(4))因成本低且稳定性高在光催化产氢领域备受关注。然而,纯g-C_(3)N_(4)存在表面积小、电子转移慢、光生载流子复合快等缺陷,产氢性能通常不佳。本研究通过直接热解硫酸铵和三聚氰胺混合物,成功实现硫物种对g-C_(3)N_(4)氮位点的原位取代,开发出一种高效的硫掺杂g-C_(3)N_(4) (S-g-CN)光催化剂。系列结构和光谱表征证实硫的成功掺杂。密度泛函理论的第一性原理计算表明S活性位对氢的吸附吉布斯自由能近乎为零(~0.26 eV),揭示S掺杂在优化H活性中间体吸附和解吸过程中起着重要作用。透射电子显微镜和原子力显微镜测试结果表明,S-g-CN具有超薄的纳米片状结构,其片层厚度约为2.5 nm。随后的氮气吸脱附等温线和光电化学性质测试结果表明,S掺杂不仅可显著增大g-C_(3)N_(4)比表面积,而且还能有效提高其光生电子-空穴对的转移、分离和氧化还原能力。得益于材料良好的结构特性,S-g-CN的光催化产氢速率高达4923 μmol·g^(-1)·h^(-1),是原始g-C_(3)N_(4)的28倍,超越诸多最近报道的其它S掺杂g-C_(3)N_(4)光催化剂。而且,S-g-CN的表观量子效率高达3.64%。本研究除了开发一种高效的光催化剂,还将为高性能g-C_(3)N_(4)基催化剂的设计提供有益借鉴。 展开更多
关键词 理论预测 硫掺杂 g-C_(3)N_(4) 产氢 光催化
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抑制磷酸二酯酶4可降低脑缺血/再灌注损伤后的水通道蛋白4表达、减轻星形胶质细胞肿胀 被引量:1
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作者 Kechun Chen Bingtian Xu +5 位作者 Shuqin Qiu Lu Long Qian Zhao Jiangping Xu haitao wang 唐颖馨(编译) 《神经损伤与功能重建》 2024年第6期F0003-F0003,共1页
我们的既往研究已显示磷酸二酯酶4(PDE4)抑制剂对大鼠中脑动脉闭塞/再灌注(MCAO/R)后的神经元损伤具有保护作用。然而,PDE4对脑水肿和星形胶质细胞肿胀的影响尚不清楚。在本研究中,我们发现通过Roflumilast(Roflu)抑制PDE4可以减轻大鼠... 我们的既往研究已显示磷酸二酯酶4(PDE4)抑制剂对大鼠中脑动脉闭塞/再灌注(MCAO/R)后的神经元损伤具有保护作用。然而,PDE4对脑水肿和星形胶质细胞肿胀的影响尚不清楚。在本研究中,我们发现通过Roflumilast(Roflu)抑制PDE4可以减轻大鼠缺血再灌注后的脑水肿、降低脑组织含水量。Roflu减少了水通道蛋白4(AQP4)的表达,而磷酸化蛋白激酶B(Akt)和叉头框蛋白O3a(FoxO3a)的水平增加。此外,Roflu减少原代星形胶质细胞在糖氧剥夺/再灌注(OGD/R)后的细胞体积和AQP4的表达。同样,PDE4B敲低显示出与PDE4抑制相似的作用;而PDE4B过表达可以减少PDE4B敲低对AQP4表达的抑制作用。本研究还发现,Roflu对AQP4表达和细胞体积的影响可以被Akt抑制剂MK2206阻断。神经炎症和星形胶质细胞激活是在卒中病理生理的机制之一,所以本研究用白细胞介素-1β(IL-1β)处理原代星形胶质细胞。结果显示,经IL-1β处理的星形胶质细胞表现出AQP4和磷酸化Akt及FoxO3a减少。Roflu显著降低了AQP4表达,这伴随着Akt和FoxO3a磷酸化的增加。此外,FoxO3a的过表达部分逆转了Roflu对AQP4表达的影响。本研究结果显示,PDE4抑制通过Akt/FoxO3a/AQP4通路限制了缺血诱导的脑水肿和星形胶质细胞肿胀。PDE4是脑缺血后脑水肿的一个有潜力的干预目标。 展开更多
关键词 水通道蛋白4 脑水肿 脑缺血 叉头框蛋白O3a 磷酸二酯酶4
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Does social information affect the settlement decisions of resident birds in their second breeding attempt?A case study of the Japanese Tit(Parus minor)
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作者 Xudong Li Jiangping Yu +5 位作者 Dake Yin Longru Jin Keqin Zhang Li Shen Zheng Han haitao wang 《Avian Research》 SCIE CSCD 2024年第3期326-335,共10页
Individuals may gather information about environmental conditions when deciding where to breed in order to maximize their lifetime fitness.They can obtain social information by observing conspecifics and heterospecifi... Individuals may gather information about environmental conditions when deciding where to breed in order to maximize their lifetime fitness.They can obtain social information by observing conspecifics and heterospecifics with similar ecological needs.Many studies have shown that birds can rely on social information to select their nest sites.The location of active nests and the reproductive success of conspecifics and heterospecifics can provide accurate predictions about the quality of the breeding habitat.Some short-lived species can facultatively reproduce two and/or more times within a breeding season.However,few studies have focused on how multiplebrooding individuals select nest sites for their second breeding attempts.In this study,we use long-term data to test whether the Japanese Tit(Parus minor)can use social information from conspecifics and/or heterospecifics(the Eurasian Nuthatch Sitta europaea,the Daurian Redstart Phoenicurus auroreus and the Yellow-rumped Flycatcher Ficedula zanthopygia)to select a nest site for the second breeding attempt.Our results showed that the nest boxes occupied by tits on their second breeding attempt tended to be surrounded by more breeding conspecific nests,successful first nests of conspecifics,and fewer failed first nests of conspecifics than the nest boxes that remained unoccupied(the control group).However,the numbers of breeding heterospecific nests,successful heterospecific nests,and failed heterospecific nests did not differ between the nest boxes occupied by tits on their second breeding attempt and the unoccupied nest boxes.Furthermore,the tits with local successful breeding experience tended to choose areas with more successful first nests of conspecifics than those without successful breeding experience.Thus,we suggest that conspecifics'but not heterospecifics'social information within the same breeding season is the major factor influencing the nest site selection of Japanese Tits during second breeding attempts. 展开更多
关键词 Conepeific Heterospecifie Japanese tits Multiple brooding Nest-site selection Public infomation Social information
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Knockdown of HE4 suppresses tumor growth and invasiveness in lung adenocarcinoma through regulation of EGFR signaling
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作者 YUE ZHANG WENYU YANG +5 位作者 XIAOwang HAN YUE QIAO haitao wang TING CHEN TIANYING LI WEN-BIN OU 《Oncology Research》 SCIE 2024年第6期1119-1128,共10页
It has been shown that the high expression of human epididymis protein 4(HE4)in most lung cancers is related to the poor prognosis of patients,but the mechanism of pathological transformation of HE4 in lung cancer is ... It has been shown that the high expression of human epididymis protein 4(HE4)in most lung cancers is related to the poor prognosis of patients,but the mechanism of pathological transformation of HE4 in lung cancer is still unclear.The current study is expected to clarify the function and mechanism of HE4 in the occurrence and metastasis of lung adenocarcinoma(LUAD).Immunoblotting evaluated HE4 expression in lung cancer cell lines and biopsies,and through analysis of The Cancer Genome Atlas(TCGA)dataset.Frequent HE4 overexpression was demonstrated in LUAD,but not in lung squamous cell carcinoma(LUSC),indicating that HE4 can serve as a biomarker to distinguish between LUAD and LUSC.HE4 knockdown significantly inhibited cell growth,colony formation,wound healing,and invasion,and blocked the G1-phase of the cell cycle in LUAD cell lines through inactivation of the EGFR signaling downstream including PI3K/AKT/mTOR and RAF/MAPK pathways.The first-line EGFR inhibitor gefitinib and HE4 shRNA had no synergistic inhibitory effect on the growth of lung adenocarcinoma cells,while the third-line EGFR inhibitor osimertinib showed additive anti-proliferative effects.Moreover,we provided evidence that HE4 regulated EGFR expression by transcription regulation and protein interaction in LUAD.Our findings suggest that HE4 positively modulates the EGFR signaling pathway to promote growth and invasiveness in LUAD and highlight that targeting HE4 could be a novel strategy for LUAD treatment. 展开更多
关键词 Lung adenocarcinoma Human epididymis protein 4 Epidermal growth factor receptor BIOMARKER Targeted therapies
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A food-grade and senescent cell-targeted fisetin delivery system based on whey protein isolate-galactooligosaccharides Maillard conjugate
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作者 Shuai Hou Chutong Lai +3 位作者 Yukun Song haitao wang Jialu Ni Mingqian Tan 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期688-697,共10页
Cellular senescence is the results of aging and age-related diseases,and the development of anti-aging methods may improve health and extend longevity.The natural flavonol fisetin has been shown to antagonize senescen... Cellular senescence is the results of aging and age-related diseases,and the development of anti-aging methods may improve health and extend longevity.The natural flavonol fisetin has been shown to antagonize senescence in vitro and increases longevity in vivo,but has poor water solubility and limited bioavailability.In this study,a food-grade and senescent cell-targeted delivery system for fisetin was developed based on whey protein isolate-galactooligosaccharides(WPI-GOS)Maillard conjugate,which could recognize senescence associatedβ-galactosidase in senescent cells.The fisetin nanoparticles possessed a high encapsulation efficiency,excellent dispersibility in water,good storage stability and well biocompatibility.Moreover,they could effectively accumulate and retain in senescent cells with excellent senescent cell-targeting efficacy,and inhibit the oxidative stress-induced cellular senescence in vitro.Thus,this novel nanoparticle system based on WPI-GOS Maillard conjugate showed promise to deliver hydrophobic bioactive ingredients like fisetin to senescent cells to improve their bioavailability and anti-senescence effect. 展开更多
关键词 FISETIN Nanoparticle Cellular senescence Targeted delivery
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Innovations and applications of the thermal recovery techniques for heavy oil
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作者 Huanquan Sun haitao wang +5 位作者 Xulong Cao Qinglin Shu Zheyuan Fan Guanghuan Wu Yuanliang Yang Yongchao Wu 《Energy Geoscience》 EI 2024年第4期8-19,共12页
Heavy oil represents a vital petroleum resource worldwide.As one of the major producers,China is facing great challenges in effective and economic production of heavy oil due to reservoir complexity.Plenty of efforts ... Heavy oil represents a vital petroleum resource worldwide.As one of the major producers,China is facing great challenges in effective and economic production of heavy oil due to reservoir complexity.Plenty of efforts have been made to promote innovative advances in thermal recovery modes,methods,and processes for heavy oil in the country.The thermal recovery mode has been shifted from simple steam injection to a more comprehensive“thermal+"strategy,such as a novel N2-steam hybrid process and CO_(2)-enhanced thermal recovery techniques.These advanced techniques break through the challenges of heavy oil extraction from less accessible reservoirs with thinner oil layers and greater burial depths.Regarding thermal recovery methods,China has developed the steam-assisted gravity drainage method integrating flooding and drainage(also referred to as the hybrid flooding-drainage SAGD technology)for highly heterogeneous ultra-heavy oil reservoirs and the fire flooding method for nearly depleted heavy oil reservoirs,substantially improving oil recovery.Furthermore,a range of processes have been developed for heavy oil production,including the open hole completion process using sand control screens for horizontal wells,the process of integrated injection-recovery with horizontal pump for horizontal wells,the steam dryness maintenance,measurement,and control process,efficient and environment-friendly circulating fluidized bed(CFB)boilers with high steam dryness,the recycling process of produced water,and the thermal recovery process for offshore heavy oil.Based on the advances in methodology,technology,and philosophy,a series of supporting technologies for heavy oil production have been developed,leading to the breakthrough of existing technical limit of heavy oil recovery and the expansion into new exploitation targets.For the future heavy oil production in China,it is necessary to embrace a green,low-carbon,and energy-efficient development strategy,and to expand heavy oil extraction in reservoirs with larger burial depth,more viscous oil,thinner oil layers,and lower permeability.Moreover,it is highly recommended to collaboratively maximize oil recovery and oil-to-steam ratio through technological innovations,and boost intelligentization of heavy oil production. 展开更多
关键词 Heavy oil Thermal recovery Process technology Hybrid thermal production
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遗传修饰技术在绵羊分子设计育种中的应用 被引量:8
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作者 王海涛 李亭亭 +2 位作者 黄勋 马润林 刘秋月 《遗传》 CAS CSCD 北大核心 2021年第6期580-600,共21页
利用遗传修饰技术可以使动物在遗传水平发生改变,实现在个体内表达外源基因或对其内源基因的功能造成影响。在动物育种中,可以利用遗传修饰技术在分子水平进行设计并实现品种的快速改良。从传统的遗传修饰技术、病毒载体、精子载体等介... 利用遗传修饰技术可以使动物在遗传水平发生改变,实现在个体内表达外源基因或对其内源基因的功能造成影响。在动物育种中,可以利用遗传修饰技术在分子水平进行设计并实现品种的快速改良。从传统的遗传修饰技术、病毒载体、精子载体等介导的遗传修饰技术到新型人工核酸酶介导的基因编辑技术,尤其是CRISPR/Cas9为代表的人工核酸酶的运用使得基因编辑动物的制备变得更加高效快捷,并迅速在多个物种中得到应用。这些方法也已经拓展到了绵羊(Ovis aries)遗传育种领域。利用遗传修饰技术在绵羊中进行分子育种比传统的育种方式具有更大的优势,可以使用多种策略直接对性状进行快速改良,并且可以加快育种进程。本文详细介绍了遗传修饰技术在绵羊中的研究历程,探讨了通过遗传修饰技术进行绵羊分子设计育种的可能性,并提出以上技术和方法在绵羊育种中面临的问题和挑战。 展开更多
关键词 绵羊 遗传修饰 基因编辑 动物育种
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Research on Rotating Machinery Fault Diagnosis Based on Improved Multi-target Domain Adversarial Network
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作者 haitao wang Xiang Liu 《Instrumentation》 2024年第1期38-50,共13页
Aiming at the problems of low efficiency,poor anti-noise and robustness of transfer learning model in intelligent fault diagnosis of rotating machinery,a new method of intelligent fault diagnosis of rotating machinery... Aiming at the problems of low efficiency,poor anti-noise and robustness of transfer learning model in intelligent fault diagnosis of rotating machinery,a new method of intelligent fault diagnosis of rotating machinery based on single source and multi-target domain adversarial network model(WDMACN)and Gram Angle Product field(GAPF)was proposed.Firstly,the original one-dimensional vibration signal is preprocessed using GAPF to generate the image data including all time series.Secondly,the residual network is used to extract data features,and the features of the target domain without labels are pseudo-labeled,and the transferable features among the feature extractors are shared through the depth parameter,and the feature extractors of the multi-target domain are updated anatomically to generate the features that the discriminator cannot distinguish.The modelt through adversarial domain adaptation,thus achieving fault classification.Finally,a large number of validations were carried out on the bearing data set of Case Western Reserve University(CWRU)and the gear data.The results show that the proposed method can greatly improve the diagnostic efficiency of the model,and has good noise resistance and generalization. 展开更多
关键词 multi-target domain domain-adversarial neural networks transfer learning rotating machinery fault diagnosis
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Study on Bayu Vernacular Architecture and Culture-Baxian-Old-Courtyard
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作者 Bin Chen haitao wang Yue Yang 《Journal of World Architecture》 2024年第4期7-14,共8页
The vernacular architectural culture of the Bayu region is an important part of traditional Chinese architectural culture,of which the old courtyard in Baxian is a typical representative.The purpose of this paper is t... The vernacular architectural culture of the Bayu region is an important part of traditional Chinese architectural culture,of which the old courtyard in Baxian is a typical representative.The purpose of this paper is to explore the connotation and characteristics of Bayu vernacular architectural culture,and to take the old courtyard in Baxian as a specific research object,to analyze its architectural style,cultural connotation,and its value in contemporary society.The study of the old courtyard in Baxian can not only deepen the understanding of Bayu vernacular architectural culture but also provide a useful reference for the protection and inheritance of vernacular architecture.At the same time,this paper also calls for more people to pay attention to and participate in the protection of vernacular architectural culture,and jointly guard these precious historical and cultural heritages. 展开更多
关键词 Bayu culture Vernacular architecture Baxian-Old-Courtyard Protection and utilization
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Precision Machining Equipment Fault Diagnosis Based on CWT and Improved ResNeXt
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作者 Lichen Shi Jiahang Guo haitao wang 《Instrumentation》 2024年第2期36-43,共8页
A fault diagnosis method based on continuous wavelet transform and improved multi-dimensional residual network was proposed to solve the problem that the working environment of precision machining equipment is very co... A fault diagnosis method based on continuous wavelet transform and improved multi-dimensional residual network was proposed to solve the problem that the working environment of precision machining equipment is very complicated,and the fault characteristic signal is weak and hard to extract.Firstly,the best wavelet base Cmor 3-3 is selected by comparing 6 different wavelet base types.Secondly,continuous wavelet transform(CWT)is applied to the acquired original vibration signal to generate the feature map and process the gray level.Finally,the improved ResNeXt network is used to diagnose faults in precision machining equipment.The experimental results show that the proposed CWT and the improved ResNeXt algorithm have high accuracy in identifying precision machining equipment faults in complex environments,with an average accuracy of 99.4%。 展开更多
关键词 complex working environment ResNeXt precision working equipment
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MOF-5/聚偏氟乙烯混合基质膜的制备及抗有机污染性能 被引量:2
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作者 王海涛 杨丹培 +2 位作者 吕美婵 张皓冰 常娜 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第6期57-64,70,共9页
针对聚偏氟乙烯(PVDF)超滤膜亲水性差、易污染的问题,利用金属有机骨架材料MOF-5作为添加剂,采用非溶剂诱导相分离法(NIPS)制备出MOF-5/PVDF混合基质膜并研究其抗有机污染性能。纯水通量和牛血清蛋白(BSA)截留实验表明,与基膜相比,MOF-5... 针对聚偏氟乙烯(PVDF)超滤膜亲水性差、易污染的问题,利用金属有机骨架材料MOF-5作为添加剂,采用非溶剂诱导相分离法(NIPS)制备出MOF-5/PVDF混合基质膜并研究其抗有机污染性能。纯水通量和牛血清蛋白(BSA)截留实验表明,与基膜相比,MOF-5/PVDF混合基质膜在渗透性和选择性方面都有较大提升。对比考察了改性膜和基膜的表面粗糙度、BSA静态吸附、再生性能以及不可逆有机污染率,结果表明,由于MOF-5的添加,显著降低了混合基质膜的表面粗糙度,增强了膜的抗有机污染性能。同时,分析MOF-5添加量对渗透性能和抗有机污染性能的影响,结果显示当其相对于PVDF质量分数为5%时,混合基质膜具有较好的综合性能。与基膜相比,其拉伸强度提高了48.39%,总孔隙率增加了33.3%,纯水通量增加了86.4%,水通量恢复率(FRR)提高到79.43%,不可逆污垢比(Rir)降低到20.57%。 展开更多
关键词 金属有机骨架 超滤膜 共混 膜污染 再生性能
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界面聚合反应有机溶剂对聚酰胺复合纳滤膜结构及性能的影响 被引量:2
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作者 常娜 高曌寰 +6 位作者 荆兆敬 王海涛 魏杨扬 田欣霞 张潇泰 冯厚军 王剑 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第5期32-42,共11页
聚酰胺复合纳滤膜的分离性能主要由聚酰胺分离层决定。在界面聚合反应过程中,有机相溶剂的物理性质影响两相单体在界面的溶解及扩散行为,使聚酰胺分离层微观形貌结构发生变化,从而改变膜性能。以异构烷烃混合型溶剂Isopar G,Isopar H,Is... 聚酰胺复合纳滤膜的分离性能主要由聚酰胺分离层决定。在界面聚合反应过程中,有机相溶剂的物理性质影响两相单体在界面的溶解及扩散行为,使聚酰胺分离层微观形貌结构发生变化,从而改变膜性能。以异构烷烃混合型溶剂Isopar G,Isopar H,Isopar L和Isopar M为有机相溶剂采用界面聚合法制备聚酰胺复合纳滤膜,考察上述有机相溶剂对复合纳滤膜聚酰胺交联度、分离层微观结构和聚酰胺高分子链堆积程度的影响,通过分析有机相溶剂物理性质与纳滤膜分离性能、聚酰胺层结构参数之间的相关性,探究有机相溶剂对纳滤膜分离性能的影响机制。结果表明,有机相溶剂的表面张力与聚酰胺高分子团簇的分形维数(D_(m))呈强相关性,相关性系数为-0.98;D_(m)与复合纳滤膜的水透过系数(A)呈强相关性,相关性系数为0.95,即通过选取表面张力较低的有机相溶剂,有利于提高聚酰胺高分子的分形维数,使聚酰胺具有更高的链密度,短分子链结构堆积更加疏松,从而制备具有更高水通量的聚酰胺复合纳滤膜。有机相溶剂的表面张力与A的相关性系数为-0.97,进一步印证了上述结论。 展开更多
关键词 聚酰胺 纳滤膜 小角X射线散射 界面聚合 相关性
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聚酰亚胺基导热复合材料研究进展 被引量:2
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作者 王海涛 丁栋梁 +2 位作者 刘乾 陈妍慧 张秋禹 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第8期159-166,共8页
聚酰亚胺(PI)具有优异的耐高低温性能、力学性能及耐腐蚀性能等,但其本征导热性能较差,限制了其在电子工业、航空、航天等领域应用的拓展。向PI中引入导热填料是提高材料导热性能的有效方法。文中概述了PI基导热复合材料的制备方法,归... 聚酰亚胺(PI)具有优异的耐高低温性能、力学性能及耐腐蚀性能等,但其本征导热性能较差,限制了其在电子工业、航空、航天等领域应用的拓展。向PI中引入导热填料是提高材料导热性能的有效方法。文中概述了PI基导热复合材料的制备方法,归纳了导热填料在PI基体中的存在形式,即导热填料在PI基体中构筑的空间导热通路的维数(如:一维、二维、准三维及三维导热通路),并阐述了具有不同导热通路的PI基复合材料导热性能的表现,以及适用于PI复合材料的基本导热模型,最后展望了PI基导热复合材料未来的研究方向。 展开更多
关键词 聚酰亚胺 导热 复合材料
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Petrology, geochemistry and geochronology of the Zhongcang ophiolite, northern Tibet: implications for the evolution of the Bangong-Nujiang Ocean 被引量:10
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作者 Yue Tang Qingguo Zhai +2 位作者 Peiyuan Hu Xuchang Xiao haitao wang 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第5期1369-1381,共13页
Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typi... Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typical ophiolite in the western part of the Bangong-Nujiang suture zone. It is composed of serpentinized peridotite, cumulate and isotropic gabbros, massive and pillow basalts, basaltic volcanic breccia, and minor red chert. Zircon SHRIMP Ue Pb dating for the isotropic gabbro yielded weighted mean age of 163.4 ± 1.8 Ma. Positive zircon ε Hf(t) values(+15.0 to +20.2) and mantle-like σ^(18)O values(5.29 ±0.21)% indicate that the isotropic gabbros were derived from a long-term depleted mantle source. The isotropic gabbros have normal mid-ocean ridge basalt(N-MORB) like immobile element patterns with high Mg O, low TiO_2 and moderate rare earth element(REE) abundances, and negative Nb,Ti, Zr and Hf anomalies. Basalts show typical oceanic island basalt(OIB) geochemical features, and they are similar to those of OIB-type rocks of the Early Cretaceous Zhongcang oceanic plateau within the Bangong-Nujiang Ocean. Together with these data, we suggest that the Zhongcang ophiolite was probably formed by the subduction of the Bangong-Nujiang Ocean during the Middle Jurassic. The subduction of the Bangong-Nujiang Tethyan Ocean could begin in the Earlye Middle Jurassic and continue to the Early Cretaceous, and finally continental collision between the Lhasa and Qiangtang terranes at the west Bangong-Nujiang suture zone probably has taken place later than the Early Cretaceous(ca. 110 Ma). 展开更多
关键词 Tibetan plateau Bangong-Nujiang SUTURE zone OPHIOLITE GEOCHRONOLOGY GEOCHEMISTRY SUBDUCTION
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Neurofilament proteins in axonal regeneration and neurodegenerative diseases 被引量:8
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作者 haitao wang Minfei Wu +4 位作者 Chuanjun Zhan Enyuan Ma Maoguang Yang Xiaoyu Yang Yingpu Li 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第8期620-626,共7页
Neurofilament protein is a component of the mature neuronal cytoskeleton, and it interacts with the zygosome, which is mediated by neurofilament-related proteins. Neurofilament protein regulates enzyme function and th... Neurofilament protein is a component of the mature neuronal cytoskeleton, and it interacts with the zygosome, which is mediated by neurofilament-related proteins. Neurofilament protein regulates enzyme function and the structure of linker proteins. In addition, neurofilament gene expression plays an important role in nervous system development. Previous studies have shown that neurofilament gene transcriptional regulation is crucial for neurofilament protein expression, especially in axonal regeneration and degenerative diseases. Post-transcriptional regulation increased neurofilament protein gene transcription during axonal regeneration, ultimately resulting in a pattern of neurofilament protein expression. An expression imbalance of post-transcriptional regulatory proteins and other disorders could lead to amyotrophic lateral sclerosis or other neurodegenerative diseases. These findings indicated that after transcription, neurofilament protein regulated expression of related proteins and promoted regeneration of damaged axons, suggesting that regulation disorders could lead to neurodegenerative diseases. 展开更多
关键词 axonal regeneration nerve injury neurodegenerative diseases neurofilament protein post-transcriptional regulation REVIEWS
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Function of note strings in Japanese Tit alarm calls to the Common Cuckoo:a playback experiment 被引量:10
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作者 Jiangping Yu Weiwei Lv +5 位作者 Hongwei Xu Nehafta Bibi Yangyang Yu Yunlei Jiang Wei Liang haitao wang 《Avian Research》 CSCD 2017年第3期141-146,共6页
Background: Birds produce alarm calls to convey information about threats. Some Passerine alarm calls consist of several note strings, but few studies have examined their function. Previous studies have shown that Jap... Background: Birds produce alarm calls to convey information about threats. Some Passerine alarm calls consist of several note strings, but few studies have examined their function. Previous studies have shown that Japanese Tits(Parus minor) can alter the calling rate and number and combination of notes in response to predators. We previously found the combinations of note types in Japanese Tit alarm calls to be significantly different in response to the Sparrowhawk(Accipiter nisus) and Common Cuckoo(Cuculus canorus).Methods: Through playback experiments, we tested whether the note strings in Japanese Tit alarm calls to the Common Cuckoo have different functions in conveying information. The note strings of selected alarm calls were divided into the categories of C and D, and different calls were then constructed separately based on the two note string categories. Original alarm calls(C–D), C calls and D calls were played back to male Japanese Tits during the incubation period.Results: Male Japanese Tits had a significantly stronger response to C calls than to C–D calls, and they showed a significantly stronger response to both C and C–D calls than to D calls, suggesting that Japanese Tits discriminated between the C and D calls.Conclusions: Our study demonstrated that the C-and D-category note strings of Japanese Tit alarm calls to the Common Cuckoo have different functions, which supports the previous finding that different note strings in an alarm call can provide different information to receivers. However, the exact meanings of these note strings are not yet known, and further investigation is therefore required. 展开更多
关键词 Alarm call Male Japanese Tit Note strings FUNCTION Brood parasitism PLAYBACK
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Comprehensive precursor anomaly research based on earthquake corresponding relevancy spectrum 被引量:5
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作者 haitao wang Qiong wang Lanlan Tang 《Earthquake Science》 CSCD 2009年第6期675-681,共7页
With the aim to the quantification of anomaly identification and extraction for observed or analyzed records, we present two statistical methods of earthquake corresponding relevancy spectrum (ECRS) and sliding mean... With the aim to the quantification of anomaly identification and extraction for observed or analyzed records, we present two statistical methods of earthquake corresponding relevancy spectrum (ECRS) and sliding mean relevancy (SMR). With ECRS method, we can obtain the abnormal confidence attribute of data in different value ranges. Based on the relevancy spectrum in different studied time-intervals, we convert the original time sequence into relevancy time sequence, and can obtain the SMR time series by using the multi-point cumulative sliding mean method. Then we can identify the seismic precursor anomaly. We test this method by taking the time sequence of r/-value in the northern Tianshan region as original data. The result shows that when the studied time-interval is 18 months, the precursor anomaly can be identified bet- ter from sliding mean relevancy. The anomaly corresponding rate is 83 percent, the earthquake corresponding rate is 86 per- cent, and the anomaly is characteristic of the middle term. To try the research on multi-parameter comprehensive application, we take the Kalpin tectonic block in Xinjiang as our studied region, and analyze the spatial and temporal abnormal characters of multi-parameter sliding extreme-value relevancy (MSER) before mid-strong earthquakes in the Kalpin block. The result indicates that ECRS and SMR sequence in different time-intervals can not only be used to identify the precursor anomaly of single-item data, but also offer the data of quantitative single-item anomaly for comprehensive earthquake analysis and prediction. 展开更多
关键词 earthquake corresponding relevancy spectrum(ECRS) sliding mean relevancy (SMR) multi-parameter sliding extreme-value relevancy(MSER) comprehensive precursor anomaly
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基于不同碳链长度二元酸的脂肪族聚酯的合成及性能 被引量:2
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作者 赵彩霞 柏祥 +2 位作者 王海涛 邹国享 李锦春 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第6期1-8,共8页
分别以5种不同碳链长度的脂肪族二元酸(C4、C6、C8、C10、C12)和丁二醇为单体,采用先酯化后缩聚的两步法合成一系列脂肪族聚酯:聚丁二酸丁二醇酯(PBS)、聚己二酸丁二醇酯(PBA)、聚辛二酸丁二醇酯(PBSu)、聚癸二酸丁二醇酯(PBSe)和聚十... 分别以5种不同碳链长度的脂肪族二元酸(C4、C6、C8、C10、C12)和丁二醇为单体,采用先酯化后缩聚的两步法合成一系列脂肪族聚酯:聚丁二酸丁二醇酯(PBS)、聚己二酸丁二醇酯(PBA)、聚辛二酸丁二醇酯(PBSu)、聚癸二酸丁二醇酯(PBSe)和聚十二烷二酸丁二醇酯(PBD)。研究了脂肪族二元酸单体的碳链长度对5种聚酯的结构、热性能和力学性能的影响。研究表明,5种聚酯的Mw在125000~250200之间,其结果与特性黏度具有一致性。随着脂肪族二元酸碳链长度的增加,聚酯的T_c,T_m和T_g均先降低后升高;PBSu(C8)的结晶度最高(71.2%),PBA(C6)的结晶度最低(33.8%)。随着碳链长度的增加,聚酯的初始分解温度逐渐向高温区移动,聚酯的拉伸强度逐渐降低;断裂伸长率先增加后降低,PBS(C4)的拉伸强度最大(58.55 MPa),PBSu(C8)的断裂伸长率最大(897.2%)。5种脂肪族聚酯均属于典型的假塑性流体。 展开更多
关键词 脂肪族聚酯 合成 碳链长度 热性能 力学性能
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