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Novel PtPd alloy nanoparticle-decorated g-C_3N_4 nanosheets with enhanced photocatalytic activity for H_2 evolution under visible light irradiation 被引量:7
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作者 nan xiao Songsong Li +5 位作者 Shuang Liu Boran Xu Yandong Li Yangqin Gao Lei Ge Guiwu Lu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第3期352-361,共10页
PtPd bimetallic alloy nanoparticle (NP)-modified graphitic carbon nitride (g-C3N4) nanosheet photocatalysts were synthesized via chemical deposition precipitation. Characterization of the photocatalytic H2 evolution o... PtPd bimetallic alloy nanoparticle (NP)-modified graphitic carbon nitride (g-C3N4) nanosheet photocatalysts were synthesized via chemical deposition precipitation. Characterization of the photocatalytic H2 evolution of the g-C3N4 nanosheets shows that it was significantly enhanced when PtPd alloy NPs were introduced as a co-catalyst. The 0.2 wt% PtPd/g-C3N4 composite photocatalyst gave a maximum H2 production rate of 1600.8 μmol g^–1 h^–1. Furthermore, when K2HPO4 was added to the reaction system, the H2 production rate increased to 2885.0 μmol g^–1 h^–1. The PtPd/g-C3N4 photocatalyst showed satisfactory photocatalytic stability and was able to maintain most of its photocatalytic activity after four experimental photocatalytic cycles. In addition, a possible mechanism for the enhanced photocatalytic activity was proposed and verified by various photoelectric techniques. These results demonstrate that the synergistic effect between PtPd and g-C3N4 helps to greatly improve the photocatalytic activity of the composite photocatalyst. 展开更多
关键词 g-C3N4 nanosheets PtPd alloy nanoparticles H2 evolution PHOTOCATALYSIS
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油田污水过滤罐活性炭原位氧化再生
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作者 朱博 南晓佳 +4 位作者 杨玲 王春勇 李金玉 吕雪 郑佳乐 《应用化工》 CAS CSCD 北大核心 2024年第6期1310-1314,共5页
采用过硫酸铵(APS)热活化复合超声波及甲醇萃取的方法原位再生油田污水过滤罐活性炭,考察了初始pH值、过硫酸铵用量、反应温度、反应时间、超声波强化APS功率及甲醇浓度对活性炭再生效果的影响。结果表明,APS热活化复合超声波及甲醇萃... 采用过硫酸铵(APS)热活化复合超声波及甲醇萃取的方法原位再生油田污水过滤罐活性炭,考察了初始pH值、过硫酸铵用量、反应温度、反应时间、超声波强化APS功率及甲醇浓度对活性炭再生效果的影响。结果表明,APS热活化复合超声波及甲醇萃取的方法再生效果更好。当初始pH值为7,APS溶液浓度为500 g/L,反应温度为70℃,反应时间为30 min,超声强度为60%,甲醇萃取浓度100%,再生2次,活性炭的再生效率分别为79.16%和66.84%。 展开更多
关键词 过硫酸盐 活性炭 油田污水 超声波
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3D N,O-Codoped Egg-Box-Like Carbons with Tuned Channels for High Areal Capacitance Supercapacitors 被引量:15
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作者 Feng Wei xiaojun He +3 位作者 Lianbo Ma Hanfang Zhang nan xiao Jieshan Qiu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第7期1-12,共12页
Functional carbonaceous materials for supercapacitors(SCs)without using acid for post-treatment remain a substantial challenge.In this paper,we present a less harmful strategy for preparing three-dimensional(3D)N,O-co... Functional carbonaceous materials for supercapacitors(SCs)without using acid for post-treatment remain a substantial challenge.In this paper,we present a less harmful strategy for preparing three-dimensional(3D)N,O-codoped egg-box-like carbons(EBCs).The as-prepared EBCs with opened pores provide plentiful channels for ion fast transport,ensure the e ective contact of EBCs electrodes and electrolytes,and enhance the electron conduction.The nitrogen and oxygen atoms doped in EBCs improve the surface wettability of EBC electrodes and provide the pseudocapacitance.Consequently,the EBCs display a prominent areal capacitance of 39.8μF cm-2(340 F g-1)at 0.106 m A cm-2 in 6 M KOH electrolyte.The EBC-based symmetric SC manifests a high areal capacitance to 27.6μF cm-2(236 F g-1)at 0.1075 m A cm-2,a good rate capability of 18.8μF cm-2(160 F g-1)at 215 m A cm-2 and a long-term cycle stability with only 1.9%decay after 50,000 cycles in aqueous electrolyte.Impressively,even in all-solid-state SC,EBC electrode shows a high areal capacitance of 25.0μF cm-2(214 F g-1)and energy density of 0.0233 m Wh cm-2.This work provides an acid-free process to prepare electrode materials from industrial by-products for advanced energy storage devices. 展开更多
关键词 Egg-box-like carbon Opened pores in pores Areal CAPACITANCE All-solid-state supercapacitor
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Effects of endotoxin on endothelin receptor in hepatic and intestinal tissues after endotoxemia in rats 被引量:12
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作者 Bao Hua Liu Hui Sun Chen +1 位作者 Ji Hong Zhou nan xiao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第2期298-300,共3页
INTRODUCTIONEndothelins(ETs) has a potent and sustainedvasoconstrictive effect on a variety of blood vessels.The vascular smooth muscle cell (VSMC)is thetarget for ETs.VSMC of the whole body containsendothelin recepto... INTRODUCTIONEndothelins(ETs) has a potent and sustainedvasoconstrictive effect on a variety of blood vessels.The vascular smooth muscle cell (VSMC)is thetarget for ETs.VSMC of the whole body containsendothelin receptor (ETR).A great number ofexperiments have shown that three distinctcomplementary DNAs of ETR have been identifiedi.e.,endothelin A receptor(ET_A receptor),endothelin B receptor(ET_B receptor) 展开更多
关键词 ENDOTOXIN ENDOTHELIN receptor liver INTESTINES RATS
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The roles and mechanism of cocatalysts in photocatalytic water splitting to produce hydrogen 被引量:12
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作者 nan xiao Songsong Li +3 位作者 Xuli Li Lei Ge Yangqin Gao Ning Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第4期642-671,共30页
Photocatalytic hydrogen(H2)evolution via water spilling over semiconductors has been considered to be one of the most promising strategies for sustainable energy supply in the future to provide non-pollution and renew... Photocatalytic hydrogen(H2)evolution via water spilling over semiconductors has been considered to be one of the most promising strategies for sustainable energy supply in the future to provide non-pollution and renewable energy.The key to efficient conversion of solar-chemical energy is the design of an efficient structure for high charge separation and transportation.Therefore,cocatalysts are necessary in boosting photocatalytic H2 evolution.To date,semiconductor photocatalysts have been modified by various cocatalysts due to the extended light harvest,enhanced charge carrier separation efficiency and improved stability.This review focuses on recent developments of cocatalysts in photocatalytic H2 evolution,the roles and mechanism of the cocatalysts are discussed in detail.The cocatalysts can be divided into the following categories:metal/alloy cocatalysts,metal phosphides cocatalysts,metal oxide/hydroxide cocatalysts,carbon-based cocatalysts,dual cocatalysts,Z-scheme cocatalysts and MOFs cocatalysts.The future research and forecast for photocatalytic hydrogen generation are also suggested. 展开更多
关键词 COCATALYSTS Photocatalytsts Hydrogen evolution Charge separation Water splitting
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^(18)F-FDG PET/CT在脉络膜黑色素瘤与脉络膜转移癌鉴别诊断中的应用价值
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作者 罗诗雨 李眉 +5 位作者 罗莎 王爽 张娟 李萌 南潇 鲜军舫 《首都医科大学学报》 CAS 北大核心 2022年第6期867-872,共6页
目的分析脉络膜黑色素瘤和脉络膜转移癌患者氟-18-脱氧葡萄糖(^(18)F-fluorodeoxyglucose,^(18)F-FDG)正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography,PET/CT)影像特点及代谢参数,... 目的分析脉络膜黑色素瘤和脉络膜转移癌患者氟-18-脱氧葡萄糖(^(18)F-fluorodeoxyglucose,^(18)F-FDG)正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography,PET/CT)影像特点及代谢参数,探讨其在两者的诊断及鉴别中的应用价值。方法回顾性分析2020年5月至2022年3月首次因眼部症状就诊,在首都医科大学附属北京同仁医院核医学科行^(18)F-FDG PET/CT检查,并经手术病理证实或临床最终诊断为脉络膜黑色素瘤或脉络膜转移癌的患者的影像和代谢参数。对比两组间影像学表现及^(18)F-FDG PET代谢参数,后者包括病灶最大标准化摄取值(maximum standardized uptake value,SUV_(max))、峰值标准摄取值(peak standardized uptake value,SUV_(peak))、病灶糖酵解总量(total lesion glycolysis,TLG)。应用Spearman相关性分析,评价代谢参数与病变大小之间的相关性。结果共纳入76例患者,其中脉络膜黑色素瘤58例(58只眼)、脉络膜转移癌18例(18只眼)。两组间性别、年龄、患侧差异均无统计学意义(均P>0.05)。两组间病变位置(χ^(2)=9.263,P=0.041)、形状(χ^(2)=21.735,P<0.001)差异有统计学意义。脉络膜黑色素瘤组平均隆起高度明显高于脉络膜转移癌组(t=2.539,P=0.013);两组之间基底最大径差异无统计学意义(P>0.05)。在代谢参数中,脉络膜黑色素瘤组SUV_(max)低于脉络膜转移癌组(P<0.05),两组间SUV_(peak)及TLG差异无统计学意义(均P>0.05)。脉络膜黑色素瘤组病灶SUV_(max)、SUV_(peak)、TLG与病变基底最大径(r=0.528、0.613、0.732,均P<0.001)、隆起高度(r=0.521、0.605、0.730,均P<0.001)均呈正相关。脉络膜转移癌组SUV_(peak)、TLG与病变基底最大径(r=0.528、0.661,P=0.024、0.003)、隆起高度(r=0.591、0.688,P=0.010、0.002)均呈正相关,而SUV_(max)与病变基底最大径、隆起高度均无显著相关性(均P>0.05)。结论^(18)F-FDG PET/CT影像表现及代谢参数SUV_(max)对于脉络膜黑色素瘤和转移癌的鉴别诊断有一定价值。 展开更多
关键词 脉络膜黑色素瘤 脉络膜转移癌 正电子发射型计算机断层显像/电子计算机断层显像 代谢参数 鉴别诊断
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Road Pricing Design Based on Game Theory and Multi-agent Consensus 被引量:2
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作者 nan xiao Xuehe Wang +3 位作者 Lihua Xie Tichakorn Wongpiromsarn Emilio Frazzoli Daniela Rus 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2014年第1期31-39,共9页
Consensus theory and noncooperative game theory respectively deal with cooperative and noncooperative interactions among multiple players/agents. They provide a natural framework for road pricing design, since each mo... Consensus theory and noncooperative game theory respectively deal with cooperative and noncooperative interactions among multiple players/agents. They provide a natural framework for road pricing design, since each motorist may myopically optimize his or her own utility as a function of road price and collectively communicate with his or her friends and neighbors on traffic situation at the same time. This paper considers the road pricing design by using game theory and consensus theory. For the case where a system supervisor broadcasts information on the overall system to each agent, we present a variant of standard fictitious play called average strategy fictitious play(ASFP) for large-scale repeated congestion games.Only a weighted running average of all other players actions is assumed to be available to each player. The ASFP reduces the burden of both information gathering and information processing for each player. Compared to the joint strategy fictitious play(JSFP) studied in the literature, the updating process of utility functions for each player is avoided. We prove that there exists at least one pure strategy Nash equilibrium for the congestion game under investigation, and the players actions generated by the ASFP with inertia(players reluctance to change their previous actions) converge to a Nash equilibrium almost surely. For the case without broadcasting, a consensus protocol is introduced for individual agents to estimate the percentage of players choosing each resource, and the convergence property of players action profile is still ensured. The results are applied to road pricing design to achieve socially local optimal trip timing. Simulation results are provided based on the real traffic data for the Singapore case study. 展开更多
关键词 AVERAGE strategy fictitious play(ASFP) gametheory MULTI-AGENT CONSENSUS ROAD PRICING
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Is neurotrophic factor a second language that neuron and tooth speak? 被引量:1
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作者 nan xiao 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第9期1803-1804,共2页
Neurotrophic factors are growth factors that can nourish neurons and promote neuron survival and regeneration. Dental origin mesenchymal stem cells express various neurotrophic factors during tooth development and the... Neurotrophic factors are growth factors that can nourish neurons and promote neuron survival and regeneration. Dental origin mesenchymal stem cells express various neurotrophic factors during tooth development and the expression level changes during cell differentiation. 展开更多
关键词 SPEAK differentiation. DENTAL
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Neurotrophic factors: promising candidates in tissue regeneration
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作者 nan xiao 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第5期735-736,共2页
Neurotrophic factors,also referred as neurotrophins,are growth factors originally identified in the nervous system.As indicated by the name,neurotrophic factors are essential for the survival and development of neuron... Neurotrophic factors,also referred as neurotrophins,are growth factors originally identified in the nervous system.As indicated by the name,neurotrophic factors are essential for the survival and development of neurons.Nerve growth factor(NGF)is the first identified neurotrophic factor. 展开更多
关键词 GDNF Neurotrophic factors NCT NGF
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UV-B promotes flavonoid biosynthesis in Ginkgo biloba by inducing the GbHY5-GbMYB1-GbFLS module
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作者 Sian Liu xiaoyin Gu +6 位作者 Yanbing Jiang Lu Wang nan xiao Yadi Chen Biao Jin Li Wang Weixing Li 《Horticulture Research》 SCIE CSCD 2023年第8期1-14,共14页
Ginkgo biloba(ginkgo)leaves have medicinal value due to their high levels of secondary metabolites,such as flavonoids.We found that the flavonoid content in ginkgo leaves increases significantly at high altitudes(Qing... Ginkgo biloba(ginkgo)leaves have medicinal value due to their high levels of secondary metabolites,such as flavonoids.We found that the flavonoid content in ginkgo leaves increases significantly at high altitudes(Qinghai-Tibet Plateau).Considering that high UV-B radiation is among the key environmental characteristics of the Qinghai-Tibet Plateau,we carried out simulated UV-B treatments on ginkgo seedlings and found that the flavonoid content of the leaves increased significantly following the treatments.Combined with results from our previous studies,we determined that the transcription factor GbHY5 may play a key role in responses to UV-B radiation.Overexpression of GbHY5 significantly promoted the accumulation of flavonoids in both ginkgo callus and Arabidopsis thaliana.Furthermore,yeast two-hybrid and real-time quantitative PCR showed that GbHY5 promoted the expression of GbMYB1 by interacting with GbMYB1 protein.Overexpression of GbMYB1 in ginkgo callus and A.thaliana also significantly promoted flavonoid biosynthesis.GbFLS encodes a key enzyme in flavonoid biosynthesis,and its promoter has binding elements of GbHY5 and GbMYB1.A dual-luciferase reporter assay indicated that while GbHY5 and GbMYB1 activated the expression of GbFLS individually,their co-expression achieved greater activation.Our analyses reveal the molecular mechanisms by which the UV-B-induced GbHY5-GbMYB1-GbFLS module promotes flavonoid biosynthesis in ginkgo,and they provide insight into the use of UV-B radiation to enhance the flavonoid content of ginkgo leaves. 展开更多
关键词 promoted PLATEAU treatment
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Intestinal perforation with abdominal abscess caused by extramedullary plasmacytoma of small intestine: A case report and literature review
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作者 Ke-Wei Wang nan xiao 《World Journal of Gastrointestinal Surgery》 SCIE 2022年第6期611-620,共10页
BACKGROUND Extramedullary plasmacytoma(EMP)of the gastrointestinal tract is an extremely rare disease.Clinical manifestations of EMPs are varied and depend on the location and progression of the tumor.CASE SUMMARY Her... BACKGROUND Extramedullary plasmacytoma(EMP)of the gastrointestinal tract is an extremely rare disease.Clinical manifestations of EMPs are varied and depend on the location and progression of the tumor.CASE SUMMARY Here,we firstly report a case of intestinal perforation with abdominal abscess caused by EMP of the small intestine in a 55-year-old female patient.The patient received emergency surgery immediately after the necessary preoperative procedures.During the operation,EMP was found to have caused the perforation of the small intestine and the formation of multiple abscesses in the abdominal cavity.Partial resection of the small intestine with peritoneal irrigation and drainage was performed.EMP was finally confirmed by postoperative histopathology and laboratory tests.Additionally,we performed a literature review of gastrointestinal EMP to obtain a deeper understanding of this disease.CONCLUSION EMP of the small intestine may have spontaneous perforation,which requires emergency surgery.Surgical resection can obtain good therapeutic effects. 展开更多
关键词 Extramedullary plasmacytoma PERFORATION Small intestine Gastrointestinal tract TREATMENT Case report
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Stem Cells: A Promising Therapeutic Target for COVID-19
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作者 Leyla Tahrani Hardin nan xiao 《Stem Cell Discovery》 CAS 2022年第1期1-27,共27页
A large variety of therapeutic products have been developed as vaccines or treatments of COVID-19 infection. Meanwhile SARS-CoV-2 continues to mutate and spread. The severe COVID-19 patients have limited treatment opt... A large variety of therapeutic products have been developed as vaccines or treatments of COVID-19 infection. Meanwhile SARS-CoV-2 continues to mutate and spread. The severe COVID-19 patients have limited treatment options. Therefore, mesenchymal stem cells (MSCs) are proposed as another therapeutic target. They are known for their regenerative and immunomodulatory properties. They showed potent efficacy and safety abilities for the treatment of critical COVID-19 patients and intriguing benefits in reducing lungs damage, mortality, and cytokine storm in several clinical studies. Another promising treatment option is the use of dental pulp stem cells (DPSCs) to combat SARS-CoV-2, despite the fact that detailed therapeutic strategies and mechanisms are still lacking. In this review we shed light on the immune response against COVID-19 infection and the relevant knowledge considering the role of MSCs in innate and adaptive immune responses to better understand the immune-physiological mechanisms of MSCs treatment. Lastly, we summarize the latest progress in clinical and research studies suggesting potential MSCs/DPSCs as therapeutic targets in battling COVID-19. 展开更多
关键词 ACE2 Clinical Use EXOSOMES IMMUNOTHERAPY Mesenchymal Cells SARS-CoV-2
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Thyroid Hormone Biomonitoring:A Review on Their Metabolism and Machine-Learning Based Analysis on Effects of Endocrine Disrupting Chemicals
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作者 Shijie Chen Mengjie Yu +7 位作者 Yiming Yao Yongcheng Li Ana He Zijun Zhou Liyang Pan nan xiao Haining Luo Hongwen Sun 《Environment & Health》 2024年第6期350-372,共23页
The thyroid is an essential endocrine organ in human body,and thyroid hormones(THs)are pivotal signaling molecules and mediators in various physiological processes.THs,particularly in their free form,play a critical r... The thyroid is an essential endocrine organ in human body,and thyroid hormones(THs)are pivotal signaling molecules and mediators in various physiological processes.THs,particularly in their free form,play a critical role in regulating body temperature and in the metabolism of lipid and glucose,making the maintenance of TH levels crucial for human health.THs undergo a series of metabolic processes,producing TH metabolites(THMs).THMs are significant in endocrine regulation,such as 3,5-diiothyronine(3,5-T2)and 3-iodothyronamine(3-T1AM),which exhibit activities akin to THs.The production and distribution of THMs are intricately linked to the function of specific organs and tissues,highlighting the need for advanced research into the determination and mechanisms of THMs in body.Exposure to endocrine disrupting chemicals(EDCs)can significantly affect the levels of thyroid stimulating hormone(TSH)and THs.This review utilizes machine learning to analyze epidemiological data,identifying potential EDCs that pose risks of hyperthyroidism and hypothyroidism.Additionally,it delves into the toxicological mechanisms of these EDCs,examining their effects on TH production,binding processes,related proteins,and metabolic enzymes.This approach effectively bridges the gap between epidemiological studies and toxicological researches,laying the groundwork for future research trends.By integrating epidemiological studies with machine learning,this review offers insightful perspectives on the potential risks associated with chemical exposure and underscores the necessity for further research in understanding the impact of EDCs on TH metabolism and TH-related health effects. 展开更多
关键词 Thyroid stimulating hormone Emerging contaminants Data mining THYROXINE 3 3′ 5-Triiodothyronine HOMEOSTASIS
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问题导向/翻转课堂教学在生物工程专业“化工原理”课程中的应用探索 被引量:20
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作者 李璐 肖南 +1 位作者 解新安 李雁 《生物工程学报》 CAS CSCD 北大核心 2020年第9期1939-1946,共8页
新工科建设要求探索符合时代特征和工程教育规律的培养模式。针对"化工原理"课程特点和传统教学方法的局限性,将问题导向教学法与翻转课堂教学模式融合,用于生物工程等专业该课程的教学改革与实践。通过对课前知识学习、课中... 新工科建设要求探索符合时代特征和工程教育规律的培养模式。针对"化工原理"课程特点和传统教学方法的局限性,将问题导向教学法与翻转课堂教学模式融合,用于生物工程等专业该课程的教学改革与实践。通过对课前知识学习、课中知识内化、课后巩固拓展3个阶段的系统教学设计,有效激发学生的学习兴趣和积极性,培养学生的自主学习能力和工程思维,取得了较好的教学效果,可为农业院校化工原理及食品工程原理课程建设和工程人才培养提供参考和借鉴。 展开更多
关键词 问题导向 翻转课堂 化工原理 评价
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基于螺噁嗪的快速可逆力响应性聚合物的研究 被引量:1
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作者 肖楠 于恒哲 +4 位作者 高文莉 阮永红 郑锦丽 许元泽 翁文桂 《高分子学报》 SCIE CAS CSCD 北大核心 2021年第9期1053-1057,共5页
机械力响应性聚合物的设计目前引起国内外广泛的关注,但力致变色聚合物中的力色团的设计仍然是巨大的挑战.本工作设计并合成了一种全新的螺噁嗪力色团结构,并将其引入以聚二甲基硅氧烷(PDMS)为基体的聚合成交联网络结构中.通过对螺噁嗪... 机械力响应性聚合物的设计目前引起国内外广泛的关注,但力致变色聚合物中的力色团的设计仍然是巨大的挑战.本工作设计并合成了一种全新的螺噁嗪力色团结构,并将其引入以聚二甲基硅氧烷(PDMS)为基体的聚合成交联网络结构中.通过对螺噁嗪小分子溶液和聚合物的紫外光照射验证了螺噁嗪力色团结构在紫外光刺激下的响应性以及快速恢复性;拉伸和循环拉伸实验来验证聚合物优异的力致变色行为;从CIE图则更加直观地看到聚合物在拉伸过程中由无色变为红色而撤掉机械力瞬间变为蓝色并在短暂时间内恢复为无色.综上本文主要介绍了一种全新的力色团结构基于PDMS所制备出的柔性高分子材料,由于其优异的力致变色性能以及快速恢复性,在应力示警、柔性变色材料传感器方面都有一定的潜力. 展开更多
关键词 响应性高分子 力色团 力致变色 可逆
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海南岛景心角海滩老鼠艻(Spinifex littoreus)灌丛沙堆沉积及形态特征 被引量:6
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作者 黄钦妮 董治宝 +7 位作者 肖南 冯淼彦 石寰宇 陈国祥 白子怡 张欣 高冲 王晓枝 《中国沙漠》 CSCD 北大核心 2021年第6期157-168,共12页
灌丛沙堆是海岸带广泛发育的风积地貌,海南岛东北部海岸发育着典型的老鼠艻(Spinifex littoreus)灌丛沙堆。通过野外考察和室内实验,并结合气象数据对海南岛文昌海岸景心角海滩老鼠艻灌丛沙堆的形成动力条件、沉积物粒度、地球化学元素... 灌丛沙堆是海岸带广泛发育的风积地貌,海南岛东北部海岸发育着典型的老鼠艻(Spinifex littoreus)灌丛沙堆。通过野外考察和室内实验,并结合气象数据对海南岛文昌海岸景心角海滩老鼠艻灌丛沙堆的形成动力条件、沉积物粒度、地球化学元素特征和形态进行系统分析。结果表明:稳定的向岸风以及开阔的沙质海滩是灌丛沙堆发育的基本条件;较低的风能环境和滩肩的"贝壳碎屑物带"是景心角灌丛沙堆规模较小的主要原因;景心角老鼠艻灌丛沙堆形态以锥型和蝌蚪型为主;与沙堆迎风坡相比,背风坡坡长对沙堆的长轴影响较大,而沙堆的长轴和迎风坡坡长则对沙堆高度的影响更突出;老鼠艻灌丛水平方向上的生长更能影响沙堆形态的发育。 展开更多
关键词 灌丛沙堆 沉积特征 形态 老鼠艻(Spinifex littoreus) 海南岛
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Transrectal microwave thermotherapy causing a short-time influence on sperm quality in Chinese chronic nonbacterial prostatitis patients 被引量:4
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作者 Jia-Xin Jin Han-Zhang Wang +5 位作者 Zheng-Xing Zhai Bao-Liang Ma Qin-Fang Li nan xiao Zhi-Ping Wang Ronald Rodriguez 《Asian Journal of Andrology》 SCIE CAS CSCD 2017年第5期548-553,共6页
Chronic prostatitis can affect the sperm's quality. Previous studies have shown that transrectal microwave thermotherapy (TRMT) results in symptomatic relief in patients with chronic prostatitis, but the effects on... Chronic prostatitis can affect the sperm's quality. Previous studies have shown that transrectal microwave thermotherapy (TRMT) results in symptomatic relief in patients with chronic prostatitis, but the effects on sperm have not been carefully investigated. This study evaluates the impact of TRMT on the relief or decrease of symptoms and quality of sperm when used to treat patients with chronic nonbacterial prostatitis. Sixty patients were enrolled in the study. TRMT treatment was administered over 5 days, 1 h per day. Semen examination was carried out pretreatment and immediately at the conclusion of the 5-day treatment. Also, it was repeated 1 month, 3 months, and 6 months later. The treatment's symptom relief efficacy was evaluated using the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI). After the treatment, the overall NIH-CPSI scores were lower compared to those of pretreatment. In addition, the white blood cells and lecithin in expressed prostatic secretion were normal after the treatment. The sperm count was decreased by 23.8% 3 months after the treatment, sperm motility was reduced by 10.3% immediately after treatment, and sperm deformity was increased by 17.2%. The sperm volume and PH were not affected. However, the sperm quality recovered after treatment and the malformation rate was also lower at 6 months after treatment. TRMT is a favorable and safe treatment option for patients with nonbacterial chronic prostatitis. It could relieve the patient's symptoms and impact on sperm quality in the short-term. 展开更多
关键词 chronic pelvic pain symptom chronic prostatitis sperm quality transrectal microwave thermotherapy
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Single-molecule observation of mechanical isomerization of spirothiopyran and subsequent Click addition 被引量:1
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作者 Ruixiang Yao Xun Li +2 位作者 nan xiao Wengui Weng Wenke Zhang 《Nano Research》 SCIE EI CSCD 2021年第8期2654-2658,共5页
Spirothiopyran(STP)is particularly attractive when used as a mechanophore to endow polymers with both damage-signaling and.self-reinforcing capacity.It is,however,not clear the actual force required to induce the cycl... Spirothiopyran(STP)is particularly attractive when used as a mechanophore to endow polymers with both damage-signaling and.self-reinforcing capacity.It is,however,not clear the actual force required to induce the cycloreversion of STP into ring-opened thiomerocyanine(TMC),which reacts spontaneously with activated C=C bonds.Here,we used atomic force microscopy(AFM)-based single molecule force spectroscopy(SMFS)to study the mechanochemistry of STP mechanophore.It is found that the ring-opening of STP at room temperature requires forces of-200-400 pN,depending on the pulling speed.In addition,the reversibility of STP to TMC isomerization is demonstrated.Finally,mechanochemically induced intermolecular Click addition is achieved in single'molecule level by pulling STP in the presence of maleimide. 展开更多
关键词 single-molecule force spectroscopy spirothiopyran mechanophore Click addition polymer mechanochemistry
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Bronchiectasis with Nocardia infection was designated as Lady Windermere-like syndrome:a retrospective study 被引量:1
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作者 Pu Zeng xiaofei Zhang +3 位作者 Huaxu Wu Lijun Wang nan xiao Xiangdong Mu 《Chinese Medical Journal》 SCIE CAS CSCD 2023年第15期1864-1866,共3页
To the Editor:It is well-known that bronchiectasis with non-tuberculous mycobacterial(NTM)infection,commonly reported in female never-smokers,is termed as Lady Windermere syndrome(LWS).The concept of LWS was first pro... To the Editor:It is well-known that bronchiectasis with non-tuberculous mycobacterial(NTM)infection,commonly reported in female never-smokers,is termed as Lady Windermere syndrome(LWS).The concept of LWS was first proposed in 1992.[1]Polite and graceful women without previous lung disease might have the habit of voluntary cough suppression,which is responsible for lung infections,especially bronchial dilation in the middle lobe and lingular segment combined with Mycobacterium avium complex(MAC)infection.In clinical practice,we found that bronchiectasis with pulmonary nocardiosis also more frequently occurs in middle-aged and elderly women without history of smoking,and its microbial characteristics,clinical presentations,and radiographic findings are highly analogous to those of LWS.In this research,we retrospectively analyzed data of patients with bronchiectasis with NTM and bronchiectasis complicated with Nocardia infection who were admitted to our hospital in recent years,and studied their similarities and differences in clinical characteristics. 展开更多
关键词 INFECTION admitted LUNG
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阿基米德铺砌柱面互承构型的可行性判定
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作者 陆飞云 徐霄雁 +1 位作者 肖南 金阳 《钢结构(中英文)》 2020年第4期28-38,共11页
互承结构由来已久,因节点简单、施工方便、造型美观等优点而受到学术界和工程界的关注。然而,互承结构中大量几何约束的存在,导致其构型困难,这成为了互承结构应用的一大障碍。为了寻找在给定曲面上生成互承构型的可行方案,探究了阿基... 互承结构由来已久,因节点简单、施工方便、造型美观等优点而受到学术界和工程界的关注。然而,互承结构中大量几何约束的存在,导致其构型困难,这成为了互承结构应用的一大障碍。为了寻找在给定曲面上生成互承构型的可行方案,探究了阿基米德铺砌的几何用于柱面互承构型的可行性。对于柱面网格生成互承构型的可行性判定,其判定流程为先进行平面预判定,然后对柱面网格进行直接转换,再通过三层次判定法或快捷判定法进行判定。11种阿基米德平面铺砌以不同的对称轴为纵轴弯曲,可生成21种阿基米德铺砌柱面网格,因此采用收缩法、旋转法和扩展平移法这3种直接转换法生成互承构型存在63种可能方案。对这63种方案展开系统性的判定筛选分析。首先,通过平面预判定和三层次判定法中结点单元的物理判定可获得某些不可行方案的典型特征,根据这些特征对阿基米德铺砌柱面网格形式进行批量预处理,排除一部分不可行的方案。对剩下的方案,采用自编的MATLAB程序,对柱面网格用收缩法、旋转法和扩展平移法进行直接转换,之后,采用三层次判定法和快捷判定法进行逐一判断。研究结果表明:63种可能方案中,理论上满足互承构型要求的有6种,分别是A1②的收缩法和旋转法、A2②的扩展平移法、A3②的收缩法和旋转法以及A3①的收缩法,并同时给出了这6种可行方案的解析解。这6种构型的网格都具有单元几何形状单一、二度旋转对称且整体形态规则的特点。为实证研究结果,对其中5种可行方案,搭建了实体互承模型。 展开更多
关键词 阿基米德铺砌 柱面网格 互承构型 可行性判定 实体互承模型
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