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Experimental study on the effect of wind on pointing accuracy of antenna structures
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作者 Li Fu Wang Li +5 位作者 Lingling Wang wen guo Qinghui Liu Zhiqiang Shen Xu Wang Haiming Liu 《Astronomical Techniques and Instruments》 CSCD 2024年第5期284-294,共11页
Wind loads have instantaneity and turbulence characteristics that will lead to pointing errors in antenna structures,and these errors cannot be ignored in high-frequency observations.Using the Tianma 65 m radio telesc... Wind loads have instantaneity and turbulence characteristics that will lead to pointing errors in antenna structures,and these errors cannot be ignored in high-frequency observations.Using the Tianma 65 m radio telescope(TMRT)as an example object,the pointing errors caused by wind loads are investigated using an accelerometer system.First,the resonant frequency range of the antenna structure is used for reference to acquire useful signals through the bandpass filtering method.Then,the direct current(DC)component of these signals is filtered out using the fast discrete Fourier transform method,and the baseline of the acceleration is corrected using the least-squares method.Finally,the acceleration integral is solved approximately using the discrete trapezoidal area method,and the structural vibration displacement of the antenna is determined using a double integral of acceleration.The pointing errors are then obtained based on the displacement relationship between the primary and subreflector surfaces.When the wind speed is 3.2 m/s,the antenna pitch angle is 61.7°and the wind direction angle is 80°,the generated pitch pointing error is 3.05'',and the azimuth pointing error is 1.14''.These results are consistent with those obtained via inclinometer measurements,thus validating the signal processing method and the pointing error calculation method proposed in this paper.The research methods and data analysis results reported here provide a basis for further wind-induced pointing error correction studies. 展开更多
关键词 ACCELEROMETER Double integral Pointing error Bandpass filtering
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Design and Research of Active Gravity Unloading Device for Large Aperture Optical Mirror
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作者 Qiuyue Yu Zhaoming Wang +6 位作者 Qiushi Yang wen guo Chunlin Li Yonggang Wang Mengjuan Li Jianhua Zhang Chao Wang 《Optics and Photonics Journal》 2023年第7期167-177,共11页
The large aperture optical mirror for space is processed and tested in the gravity environment on the ground. After entering space, gravity disappears due to the change of environment, and the mirror surface that has ... The large aperture optical mirror for space is processed and tested in the gravity environment on the ground. After entering space, gravity disappears due to the change of environment, and the mirror surface that has met the engineering requirements on the ground will change, seriously affecting the imaging quality. In order to eliminate the influence of gravity and to ensure the consistency of space and ground, gravity unloading must be performed. In order to meet the requirements of processing and testing for the large aperture space mirror in the state of vertical optical axis, a universal gravity unloading device was proposed. It was an active support and used air cylinders to provide accurate unloading force. First, the design flow of gravity unloading was introduced;then the detailed design of the mechanical structure and control system was given;then the performance parameters of the two types of cylinders were tested and compared, including the force-pressure relationship curve and the force-position relationship curve;finally, the experimental verification of the gravity unloading device was carried out;for a mirror with an aperture of ?2100 mm, the gravity unloading device was designed and a vertical detection optical path was built. The test results showed that by using this gravity unloading device, the actual processing surface accuracy of the mirror was better than 1/50λ-RMS, which met the application requirement of the optical system. Thus, it can be seen that using this gravity unloading device can effectively unload the gravity of the mirror and realize the accurate processing and measurement of the mirror surface. . 展开更多
关键词 Optical Mirror Large Aperture Active Support Gravity Unloading
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低温条件下提高连续混配施工稳定性研究 被引量:2
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作者 谢新秋 文果 马新东 《石油化工应用》 CAS 2019年第1期59-61,80,共4页
长庆油田水平井施工方式以连续混配为主,但是在冬季低温情况下,胍胶溶胀差,基液黏度低,交联液携砂能力差,达不到施工要求。室内研究表明,通过调整配液p H值、添加剂添加顺序、延长胍胶溶胀时间等方法,配制携砂液交联性能好。现场施工过... 长庆油田水平井施工方式以连续混配为主,但是在冬季低温情况下,胍胶溶胀差,基液黏度低,交联液携砂能力差,达不到施工要求。室内研究表明,通过调整配液p H值、添加剂添加顺序、延长胍胶溶胀时间等方法,配制携砂液交联性能好。现场施工过程中,提前把胍胶基液用水pH值调整到合理值;增加缓冲罐,提前配制胍胶基液,延长溶胀时间;调整添加剂添加顺序等方式,现场施工表明交联液携砂能力好,满足施工要求。 展开更多
关键词 交联液 PH值 添加顺序 溶胀时间
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多倍体与二倍体枇杷叶片特征及抗旱性初步分析 被引量:17
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作者 温国 孙皓浦 +5 位作者 党江波 蒋朋飞 王金英 杨垚 郭启高 梁国鲁 《果树学报》 CAS CSCD 北大核心 2019年第8期968-979,共12页
【目的】探讨多倍体与二倍体枇杷(Eriobotrya japonica Lindl.)叶片生理形态特征差异并进行抗旱性初步评价,为枇杷倍性鉴定及抗旱性评价提供参考。【方法】以4个系列18个不同倍性枇杷株系为试验材料,对各株系叶片的形态解剖结构、失水率... 【目的】探讨多倍体与二倍体枇杷(Eriobotrya japonica Lindl.)叶片生理形态特征差异并进行抗旱性初步评价,为枇杷倍性鉴定及抗旱性评价提供参考。【方法】以4个系列18个不同倍性枇杷株系为试验材料,对各株系叶片的形态解剖结构、失水率(RWL)、营养元素含量、叶绿素(Chl)含量进行观察、测定和分析。通过隶属函数法,对其抗旱能力进行初步评价。【结果】枇杷叶片长度、宽度与倍性呈极显著正相关(p<0.01),叶形指数与倍性呈极显著负相关(p<0.01);10项枇杷叶片解剖结构指标与倍性关联度强弱排序依次为:下表皮、上角质层、海绵组织、叶片组织细胞结构疏松度(SR)、叶厚、叶片组织细胞结构紧密度(CTR)、下角质层、栅栏组织、栅栏组织细胞层数、上表皮,其中上角质层、下角质层、CTR与倍性呈负相关;在40℃下干旱处理6 h后,A系列、H系列、K系列失水率与倍性均呈负相关,在24 h后失水率与倍性呈显著负相关(p<0.05);氮(N)、磷(P)、钾(K)、铁(Fe)、叶绿素a(Chl.a)、叶绿素b(Chl.b)、总叶绿素含量Chl.(a+b)含量与倍性关联度强弱排序依次为:N、K、P、Chl.b、Chl.(a+b)、Fe、Chl.a,其中N、P、K含量与倍性呈负相关;参考枇杷叶片解剖结构与失水率进行抗旱性隶属函数分析:‘A313’(3x)、‘A322’(3x)、‘B350’(3x)、‘B431’(4x)、‘4X(2)’(4x)、‘H324’(3x)、‘K3’(3x)、‘K4’(4x)抗旱性均强于同系列二倍体。【结论】枇杷叶片生理形态指标可作为枇杷倍性鉴定的参考指标,抗旱性评价中的8个抗旱性强的多倍体枇杷材料可用于进一步抗旱性研究,培育多倍体可作为提高枇杷抗旱性的一种途径。 展开更多
关键词 枇杷 多倍体 生理形态特征 抗旱性 隶属函数法
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鼻咽癌治疗相关听力损伤研究进展 被引量:3
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作者 文果 覃玉桃 《中华耳科学杂志》 CSCD 北大核心 2018年第5期640-645,共6页
鼻咽癌治疗相关听力损伤已成为治疗后的常见并发症之一,其听力损伤可表现为传导性听力下降、感音神经性听力下降或混合性听力下降。研究表明,放射线、化疗药物(主要是顺铂)具有耳毒性,且二者耳毒性具有协同作用。文章阐述放射线、化疗药... 鼻咽癌治疗相关听力损伤已成为治疗后的常见并发症之一,其听力损伤可表现为传导性听力下降、感音神经性听力下降或混合性听力下降。研究表明,放射线、化疗药物(主要是顺铂)具有耳毒性,且二者耳毒性具有协同作用。文章阐述放射线、化疗药物(以顺铂为主)的听力损伤机制,辐射剂量、顺铂剂量与听力损伤关系,以及听力损伤的预防和治疗,旨在提高对鼻咽癌治疗后听力损伤的认识,唤起对听功能保护的重视。 展开更多
关键词 鼻咽癌 放射治疗 化疗 听力损伤 预防及治疗
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Is seawater geochemical composition recorded in marine carbonate? Evidence from iron and manganese contents in Late Devonian carbonate rocks 被引量:7
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作者 Zhe Wang wen guo +4 位作者 Ting Nie Haoran Ma Tianzheng Huang Yuanlin Sun Bing Shen 《Acta Geochimica》 EI CAS CSCD 2019年第2期173-189,共17页
Iron and manganese are the important redoxsensitive elements in the ocean. Previous studies have established a series of paleo-depositional redox proxies based on the form and content of iron in sedimentary rocks(e.g.... Iron and manganese are the important redoxsensitive elements in the ocean. Previous studies have established a series of paleo-depositional redox proxies based on the form and content of iron in sedimentary rocks(e.g., degree of pyritization, FeHR/FeT, Fe/Al). These proxies were developed and applied on siliciclastic-rich marine sediments. Although marine carbonate rocks are generally considered to preserve the geochemical signals of ancient seawater, neither Fe nor Mn content in marine carbonate rocks(Fecarb, Mncarb) has been independently used as a proxy to quantify environmental cues in paleo-oceans. Both Fe and Mn are insoluble in oxic conditions(Fe_2O_3, Fe(OH)_3,MnO_2), while their reduced forms(Fe^(2+) and Mn^(2+)) are soluble. Therefore, oxic seawater should have low concentrations of dissolved Fe^(2+)and Mn^(2+), and accordingly carbonate rocks precipitated from oxic seawater should have low Fecarband Mncarb, and vice versa. To evaluate whether Fecarband Mncarbcan be used to quantify oxygen fugacity in seawater, we measured Fecarband Mncarbof Upper Devonian marine carbonate rocks collected from nine sections in South China. Fecarbof intraplatform basin samples wassignificantly higher than that of shelf samples, while shelf and basin samples had comparable Mncarb. The modeling result indicates that the dramatic difference in Fecarbcannot be explained by variation in oxygen fugacity between the shelf and basin seawater. Instead, both Fecarband Mncarb appear to be more sensitive to benthic flux from sediment porewater that is enriched in Fe^(2+)and Mn^(2+). Porewater Fe^(2+)and Mn^(2+)derive from bacterial iron and manganese reduction; flux was controlled by sedimentation rate and the depth of the Fe(Mn) reduction zone in sediments, the latter of which is determined by oxygen fugacity at the water–sediment interface. Thus, high Fecarbof the basin samples might be attributed to low sedimentation rate and/or low oxygen fugacity at the seafloor. However, invariant Mncarbof the shelf and basin samples might be the consequence of complete reduction of Mn in sediments. Our study indicates that marine carbonate rocks may not necessarily record seawater composition, particularly for benthic carbonate rocks. The influence of benthic flux might cause carbonate rocks' geochemical signals to deviate significantly from seawater values. Our study suggests that interpretation of geochemical data from carbonate rocks, including carbonate carbon isotopes, should consider the process of carbonate formation. 展开更多
关键词 CARBONATE ROCKS Fe CONTENT Mn CONTENT Oxygen FUGACITY BENTHIC flux
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Diagnostic classification of endosonography for differentiating colorectal ulcerative diseases: A new statistical method 被引量:7
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作者 En-Qi Qiu wen guo +4 位作者 Tian-Ming Cheng Yong-Li Yao Wei Zhu Si-De Liu Fa-Chao Zhi 《World Journal of Gastroenterology》 SCIE CAS 2017年第46期8207-8216,共10页
AIM To establish a classification method for differential diagnosis of colorectal ulcerative diseases, especially Crohn's disease(CD), primary intestinal lymphoma(PIL) and intestinal tuberculosis(ITB).METHODS We s... AIM To establish a classification method for differential diagnosis of colorectal ulcerative diseases, especially Crohn's disease(CD), primary intestinal lymphoma(PIL) and intestinal tuberculosis(ITB).METHODS We searched the in-patient medical record database for confirmed cases of CD, PIL and ITB from 2008 to 2015 at our center, collected data on endoscopic ultrasound(EUS) from randomly-chosen patients who formed the training set, conducted univariate logistic regression analysis to summarize EUS features of CD, PIL and ITB, and created a diagnostic classification method. All cases found to have colorectal ulcers using EUS were obtained from the endoscopy database and formed the test set. We then removed the cases which were easily diagnosed, and the remaining cases formed the perplexing test set. We re-diagnosed the cases in the three sets using the classification method, determined EUS diagnostic accuracies, and adjusted the classification accordingly. Finally, the re-diagnosing and accuracy-calculating steps were repeated.RESULTS In total, 272 CD, 60 PIL and 39 ITB cases were diagnosed from 2008 to 2015 based on the in-patient database, and 200 CD, 30 PIL and 20 ITB cases were randomly chosen to form the training set. The EUS features were summarized as follows: CD: Thickened submucosa with a slightly high echo level and visible layer; PIL: Absent layer and diffuse hypoechoic mass; and ITB: Thickened mucosa with a high or slightly high echo level and visible layer. The test set consisted of 77 CD, 30 PIL, 23 ITB and 140 cases of other diseases obtained from the endoscopy database. Seventy-four cases were excluded to form the perplexing test set. After adjustment of the classification, EUS diagnostic accuracies for CD, PIL and ITB were 83.6%(209/250), 97.2%(243/250) and 85.6%(214/250) in the training set, were 89.3%(241/270), 97.8%(264/270) and 84.1%(227/270) in the test set, and were 86.7%(170/196), 98.0%(192/196) and 85.2%(167/196) in the perplexing set, respectively.CONCLUSION The EUS features of CD, PIL and ITB are different. The diagnostic classification method is reliable in the differential diagnosis of colorectal ulcerative diseases. 展开更多
关键词 Endoscopic ultrasound Ulcerative diseases Crohn’s disease Primary intestinal lymphoma Intestinal tuberculosis CLASSIFICATION
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Chemical deactivation of Cu-SAPO-18 deNO_x catalyst caused by basic inorganic contaminants in diesel exhaust 被引量:7
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作者 Shujun Ming Lei Pang +5 位作者 Chi Fan wen guo Yahao Dong Peng Liu Zhen Chen Tao Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第4期590-599,M0005,共11页
Contaminants(K,Na,Ca,and Mg)were introduced into Cu-SAPO-18 via incipient wetness impregnation to investigate their effect on the selective catalytic reduction of NOx with NH3(NH3-SCR)over Cu-SAPO-18.After the introdu... Contaminants(K,Na,Ca,and Mg)were introduced into Cu-SAPO-18 via incipient wetness impregnation to investigate their effect on the selective catalytic reduction of NOx with NH3(NH3-SCR)over Cu-SAPO-18.After the introduction of contaminants into Cu-SAPO-18,the quantity of acidic sites and Cu^2+ species in catalyst decreases owing to the replacement of H^+ and Cu^2+ by K^+,Na^+,Ca^2+,and Mg^2+.Furthermore,the loss of isolated Cu^2+ induces the generation of CuO and CuAl2O4-like phases,which causes further loss in the Brunauer-Emmett-Teller surface area of the catalyst.Consequently,the deNOx performance of the contaminated Cu-SAPO-18 catalysts drops.Such decline in NH3-SCR performance becomes more pronounced by increasing the contaminant contents from 0.5 to 1.0 mmol/gcatal.In addition,the deactivation influence of the contaminants on Cu-SAPO-18 is presented in the order of K>Na>Ca>Mg,which is consistent with the order of reduction of acidic sites.To a certain degree,the effect of the acidic sites on the deactivation of Cu-SAPO-18 might be more significant than that of isolated Cu2+ and the catalyst framework.Moreover,kinetic analysis of NH3-SCR was conducted,and the results indicate that there is no influence of contaminants on the NH3-SCR mechanism. 展开更多
关键词 Cu-SAPO-18 catalyst Basic inorganic contaminant Selective catalytic reduction of NOx with NH3 Acidic site Isolated Cu……2+
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Slow-pull and different conventional suction techniques in endoscopic ultrasound-guided fine-needle aspiration of pancreatic solid lesions using 22-gauge needles 被引量:3
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作者 Jia-Ying Chen Qing-Yu Ding +4 位作者 Yang Lv wen guo Fa-Chao Zhi Si-De Liu Tian-Ming Cheng 《World Journal of Gastroenterology》 SCIE CAS 2016年第39期8790-8797,共8页
AIM To evaluate the cytological diagnostic capacity and sample quality of the slow-pull technique and compare them with different suction techniques.METHODS From July 2010 to December 2015, 102 patients with pancreati... AIM To evaluate the cytological diagnostic capacity and sample quality of the slow-pull technique and compare them with different suction techniques.METHODS From July 2010 to December 2015, 102 patients with pancreatic solid lesions who underwent endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA) with 22-gauge needles were retrospectively evaluated. EUS-FNA diagnosis was based on a cytological examination, and final diagnosis was based on a comprehensive standard of cytological diagnosis, surgical pathology and clinical or imaging follow-up. Cytological specimens were characterized for cellularity and blood contamination. The cytological diagnostic capacity and sample quality of the slow-pull technique and suction techniques with 5-m L/10-m L/20-m L syringes were analyzed.RESULTS Of all of the EUS-FNA procedures, the slow-pull technique and suction techniques with 5-m L/10-m L/20-m L syringes were used in 31, 19, 34 and 18 procedures, respectively. There were significant differences between these four suction techniques in terms of cytological diagnostic accuracy(90.3% vs 63.2% vs 58.8% vs 55.6%, P = 0.019), sensitivity(88.2% vs 41.7% vs 40.0% vs 36.4%, P = 0.009) and blood contamination(score ≥ 2 for 29.0% vs 52.6% vs 70.6% vs 72.2%, P = 0.003). The accuracy and sensitivity of the slow-pull technique were significantly higher than those of the suction techniques using 5-m L(P = 0.03, P = 0.014), 10-m L(P = 0.005; P = 0.006) and 20-mL syringes(P = 0.01, P = 0.01). Blood contamination was significantly lower in the slow-pull technique than in the suction techniques with 10-m L(P = 0.001) and 20-mL syringes(P = 0.007).CONCLUSION The slow-pull technique may increase the cytological diagnostic accuracy and sensitivity with slight blood contamination during EUS-FNA when using 22-gauge needles for solid pancreatic masses. 展开更多
关键词 Endoscopic ultrasound-guided fine-needle aspiration Pancreatic solid lesion Slow-pull technique SUCTION Negative pressure CYTOLOGY
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Oxygen vacancies enriched nickel cobalt based nanoflower cathodes: Mechanism and application of the enhanced energy storage 被引量:3
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作者 Jiahui Ye Xingwu Zhai +10 位作者 Long Chen wen guo Tiantian Gu Yulin Shi Juan Hou Fei Han Yi Liu Changchun Fan Gang Wang Shanglong Peng Xuhong guo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第11期252-261,I0006,共11页
The rational design of oxygen vacancies and electronic microstructures of electrode materials for energy storage devices still remains a challenge. Herein, we synthesize nickel cobalt-based oxides nanoflower arrays as... The rational design of oxygen vacancies and electronic microstructures of electrode materials for energy storage devices still remains a challenge. Herein, we synthesize nickel cobalt-based oxides nanoflower arrays assembled with nanowires grown on Ni foam via the hydrothermal process followed annealing process in air and argon atmospheres respectively. It is found that the annealing atmosphere has a vital influence on the oxygen vacancies and electronic microstructures of resulting NiCo_(2)O_(4) (NCO-Air) and CoNiO_(2) (NCO-Ar) products, which NCO-Ar has more oxygen vacancies and larger specific surface area of 163.48 m^(2)/g. The density functional theory calculation reveals that more oxygen vacancies can provide more electrons to adsorb –OH free anions resulting in superior electrochemical energy storage performance. Therefore, the assembled asymmetric supercapacitor of NCO-Ar//active carbon delivers an excellent energy density of 112.52 Wh/kg at a power density of 558.73 W/kg and the fabricated NCO-Ar//Zn battery presents the specific capacity of 180.20 mAh/g and energy density of 308.14 Wh/kg. The experimental measurement and theoretical calculation not only provide a facile strategy to construct flower-like mesoporous architectures with massive oxygen vacancies, but also demonstrate that NCO-Ar is an ideal electrode material for the next generation of energy storage devices. 展开更多
关键词 NiCo_(2)O_(4) CoNiO_(2) SUPERCAPACITOR Oxygen vacancy defects Flower-like microstructure
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Carbon and nitrogen budget in fish-polychaete integrated aquaculture system 被引量:1
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作者 Fawen HU Ming SUN +8 位作者 Jinghui FANG guodong WANG Li LI Fengxiang GAO Yuxia JIAN Xue WANG Guangbin LIU Yan ZOU wen guo 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第3期1151-1159,共9页
Integrated multi-tropic aquaculture(IMTA)systems have been used in China for many years and have achieved significant economic,social,and ecological benefits.However,there is still a lack of benthic bioremediation spe... Integrated multi-tropic aquaculture(IMTA)systems have been used in China for many years and have achieved significant economic,social,and ecological benefits.However,there is still a lack of benthic bioremediation species that can effectively utilize the aquaculture particulate organic waste in the system.Polychaete Perinereis aibuhitensis Grube is used as an environmental remediation species for large-scale aquaculture to reduce particulate organic waste,which is of great significance to environmental protection.To improve bio-elements utilization efficiency,P.aibuhitensis was applied for IMTA indoor fish(Hexagrammos otakii)farming.Results showed that in the system,production of 1 kg of the fish discharged 2141-2338 mg of carbon and 529-532 mg of nitrogen,while in the monoculture of the fish,the figures were 3033-3390 mg and 764-794 mg,or 24.84%-35.26%and 30.35%-33.32%less,respectively.This approach promoted IMTA technology that could utilize the particulate organic waste from intensive aquaculture and reduce the adverse environmental effects. 展开更多
关键词 Perinereis aibuhitensis Grube Hexagrammos otakii integrated multi-tropic aquaculture(IMTA) carbon and nitrogen budget sediment remediation
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Calculation and decomposition of regional household energy consumption in China:based on perspectives of urbanization and residents' consumption 被引量:2
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作者 wen guo Tianyan Zhao Hongjun Dai 《Chinese Journal of Population,Resources and Environment》 2017年第2期132-141,共10页
Demographic urbanization caused great changes in scale of residents' consumption and residents' lifestyle and then impacted changes of regional household energy consumption. This paper expanded Logarithmic Mea... Demographic urbanization caused great changes in scale of residents' consumption and residents' lifestyle and then impacted changes of regional household energy consumption. This paper expanded Logarithmic Mean Decomposition Index method through introducing variables of urbanization and residential consumption into the model. It also analyzed the influences of six factors as energy structure, energy intensity, population scale, urbanization, residential consumption, and consumption inhibit on regional household energy consumption. Results showed that in 2003-2012, impact of urbanization on regional household energy consumption of Chinese three areas was significantly higher than population size. The "population gathered in eastern region" phenomenon caused eastern region getting the largest population scale effect. Driving force of residential consumption on regional household energy consumption was much higher than the other five effects. Due to the comparative advantage of residential consumption compared with government consumption, investment, and net export, the decrease of consumption ratio promoted the growth of regional household energy consumption. Energy intensity in Chinese three regions kept reducing in 2003-2012. The progress of energy utilization technology slowed the growth of regional household energy consumption, and energy intensity effect was most significant in the central region. 展开更多
关键词 Urbanization residential consumption household energy consumption
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欧洲热电业的现状和前景 被引量:4
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作者 Walter Cariani wen guo 欧盟能源技术促进组织中国〈杭州〉项目组 《能源工程》 2004年第2期7-10,共4页
介绍欧盟热电产业的概况,特别是热电联产技术的发展现状、潜力和前景,分析了影响热电发展的相关政策,同时介绍了一些欧盟成员国采取的各种鼓励措施。强调热电业的进一步发展必须与欧盟能源政策的三大目标相一致:即保障能源供应、提高工... 介绍欧盟热电产业的概况,特别是热电联产技术的发展现状、潜力和前景,分析了影响热电发展的相关政策,同时介绍了一些欧盟成员国采取的各种鼓励措施。强调热电业的进一步发展必须与欧盟能源政策的三大目标相一致:即保障能源供应、提高工业竞争力、保护环境,这些目标的实施对实现经济可持续发展和环境保护是非常必要的。 展开更多
关键词 欧洲 热电业 热电联产技术 发展现状 能源政策 环境保护 行业监管
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East Asian VLBI Network observations of active galactic nuclei jets:imaging with KaVA+Tianma+Nanshan
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作者 Yu-Zhu Cui Kazuhiro Hada +74 位作者 Motoki Kino Bong-Won Sohn Jongho Park Hyun-Wook Ro Satoko Sawada-Satoh Wu Jiang Lang Cui Mareki Honma Zhi-Qiang Shen Fumie Tazaki Tao An Ilje Cho Guang-Yao Zhao Xiao-Peng Cheng Kotaro Niinuma Kiyoaki Wajima Ying-Kang Zhang Noriyuki Kawaguchi Juan-Carlos Algaba Shoko Koyama Tomoya Hirota Yoshinori Yonekura Nobuyuki Sakai Bo Xia Yong-Bin Jiang Lin-Feng Yu Wei Gou Ju-Yeon Hwang Yong-Chen Jiang Yun-Xia Sun Dong-Kyu Jung Hyo-Ryoung Kim Jeong-Sook Kim Hideyuki Kobayashi Jee-Won Lee Jeong-Ae Lee Hua Zhang Guang-Hui Li Zhi-Qiang Xu Peng Li Jung-Hwan Oh Se-Jin Oh Chung-Sik Oh Tomoaki Oyama Duk-Gyoo Roh Katsunori-M.Shibata wen guo Rong-Bing Zhao Wei-Ye Zhong Jin-Qing Wang wen-Jun Yang Hao Yan Jae-Hwan Yeom Bin Li Xiao-Fei Li Jian-Ping Yuan Jian Dong Zhong Chen Kazunori Akiyama Keiichi Asada Do-Young Byun Yoshiaki Hagiwara Jeffrey Hodgson Tae-Hyun Jung Kee-Tae Kim Sang-Sung Lee Kunwoo Yi Qing-Hui Liu Xiang Liu Ru-Sen Lu Masanori Nakamura Sascha Trippe Na Wang Xue-Zheng Wang Bo Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第8期220-234,共15页
The East Asian Very Long Baseline Interferometry(VLBI) Network(EAVN) is a rapidly evolving international VLBI array that is currently promoted under joint efforts among China,Japan and Korea.EAVN aims at forming a joi... The East Asian Very Long Baseline Interferometry(VLBI) Network(EAVN) is a rapidly evolving international VLBI array that is currently promoted under joint efforts among China,Japan and Korea.EAVN aims at forming a joint VLBI Network by combining a large number of radio telescopes distributed over East Asian regions.After the combination of the Korean VLBI Network(KVN) and the VLBI Exploration of Radio Astrometry(VERA) into Ka VA,further expansion with the joint array in East Asia is actively promoted.Here we report the first imaging results(at 22 and 43 GHz) of bright radio sources obtained with Ka VA connected to Tianma 65-m and Nanshan 26-m Radio Telescopes in China.To test the EAVN imaging performance for different sources,we observed four active galactic nuclei(AGN) having different brightness and morphology.As a result,we confirmed that the Tianma 65-m Radio Telescope(TMRT) significantly enhances the overall array sensitivity,a factor of 4 improvement in baseline sensitivity and 2 in image dynamic range compared to the case of Ka VA only.The addition of the Nanshan 26-m Radio Telescope(NSRT) further doubled the east-west angular resolution.With the resulting high-dynamic-range,high-resolution images with EAVN(Ka VA+TMRT+NSRT),various fine-scale structures in our targets,such as the counter-jet in M87,a kink-like morphology of the 3 C 273 jet and the weak emission in other sources are successfully detected.This demonstrates the powerful capability of EAVN to study AGN jets and to achieve other science goals in general.Ongoing expansion of EAVN will further enhance the angular resolution,detection sensitivity and frequency coverage of the network. 展开更多
关键词 galaxies:active galaxies:jets instrumentation:interferometers radio continuum:galaxies
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Model-Synthesized Rate of Type Ia Supernovae and its Influence on the Chemical Enrichment of the ISM
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作者 wen guo Feng-Hui Zhang +2 位作者 Xiang-Cun Meng Zhong-Mu Li Zhan-wen Han 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第1期63-70,共8页
Using Hurley's rapid binary stellar evolution code, we have studied the model-synthesized rate of Type Ia Supernovae (SNe Ia) and its influence on the chemical enrichment of the interstellar medium ejected by stell... Using Hurley's rapid binary stellar evolution code, we have studied the model-synthesized rate of Type Ia Supernovae (SNe Ia) and its influence on the chemical enrichment of the interstellar medium ejected by stellar populations. We adopt two popular scenarios, i.e., single degenerate scenario (SD) and double degenerate scenario (DD), for the progenitors of SNe Ia to calculate the rates of SNe Ia. Rates calculated in this work agree with that of Hachisu et al. and Han & Podsiadlowski, but are different from that usually adopted in chemical evolution models of galaxies. We apply the rates of SNe Ia to the chemical enrichment (especially Fe enrichment), then compare the results with previous studies. As known SNe Ia slightly affect the enrichment of C, N, O and Mg elements, while significantly affect the enrichment of Fe. We find that the occurrence and the value of the Fe enrichment in our models are earlier and smaller than that commonly adopted in chemical evolution models. We also study the evolution of [Mg/Fe] ratios, which are almost reciprocals of the Fe enrichment. The study may provide constraints on the free parameters of chemical evolution models of galaxies and evolutionary population synthesis. 展开更多
关键词 GALAXIES abundances - supernovae general-galaxies stellar content-white dwarfs
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Discipline Planning of the Modern Glass Art
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作者 wen guo 《Review of Educational Theory》 2020年第1期50-53,共4页
The main purpose of establishing the glass art discipline in colleges and universities is to further promote the long-term development of the glass art discipline in China,and develop more talents in this field to mee... The main purpose of establishing the glass art discipline in colleges and universities is to further promote the long-term development of the glass art discipline in China,and develop more talents in this field to meet the demand of social development.Nowadays,as the promotion and popularization of glass teaching subjects,the whole level of glass art teaching has also been effectively enhanced,the abundant rich ethnic culture it contains supplies more nutrition and inspiration to the explorers.Based on this,this paper makes analysis on the planning of modern glass art for reference. 展开更多
关键词 GLASS ART DISCIPLINE TEACHING System PLANNING
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The Optimal Allocation of Investment between Antivirals and Vaccines for Influenza Pandemic Preparedness Planning
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作者 Yi Wang Yu-yuan Li wen guo 《国际感染病学(电子版)》 CAS 2012年第1期25-33,共9页
Objectives To investigate that given a fixed amount of financial resources,what is the optimal combination of vaccine and antiviral stockpiles in terms of minimizing the attack rate.Methods Mathematic modeling was use... Objectives To investigate that given a fixed amount of financial resources,what is the optimal combination of vaccine and antiviral stockpiles in terms of minimizing the attack rate.Methods Mathematic modeling was used to simulate the dynamics that with fixed influenza pandemic budget.Different budget conditions were observed if the combination changed.Framework between vaccines and antivirals was introduced by taking into account the uncertainty in vaccine and antiviral efficacy.Results Given a fixed budget,different budget allocations between vaccines and antivirals stockpile gave different attack rates.When the price of vaccine was lower than or similar with the antivirals,the attack rate increased with increasing investment in antiviral.But if the price of the vaccine was higher than the antivirals,the attack rate may not decrease with increasing investment in vaccine.Fixed the vaccine effectiveness,higher effectiveness of antiviral got a lower attack rate.When both antiviral and vaccine were with 50%probability of effectiveness,the attack rate changed by antiviral stockpile with a same pattern as they were with 100%efficacy probability,even it has a higher attack rate.Conclusions Assume the antivirals have 100%probability to be effective,budget was limited to a fix number,then in any event,population should stockpile a small amount of antivirals such that if the post-vaccination reproductive number turns out to be near 1,the additional intervention may further reduce the reproductive number to <1 and prevent the epidemic.Under the fixed budget,the price of the vaccines and antivirals will strongly affect the strategy of the stockpile allocation.When the price of vaccine is comparative lower,more investment of vaccine is better for the pandemic control,but if the vaccine price is too high then more investment in antiviral may be better.We found that attack rates and the optimal budget allocation depend on the probability to be effective of vaccine and antivirals. 展开更多
关键词 Influenza pandemic PREPAREDNESS ALLOCATION INVESTMENT
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Devonian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas 被引量:2
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作者 wenkun QIE Kun LIANG +9 位作者 wen guo Biao GAO Junjun SONG Bo CHEN Pu HUANG Li QIAO Honghe XU Jitao CHEN Yucong SUN Yichun ZHANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第4期1036-1070,共35页
The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in fossils.It records the crucial processes of continuous subduction and reduction of t... The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in fossils.It records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern hemisphere.Thus,it is of great significance for explaining the global paleogeographic evolution,tectonic activities and biodiversity changes during this critical period.The blocks on both sides of the southern Tienshan suture zone and the Longmu Co-ShuanghuChangning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions,showing important tectonic paleogeographic partitioning significance.The two suture zones represent the main branches of the PaleoAsian Ocean and the Paleo-Tethys Ocean,respectively,and on this basis the Devonian System can be subdivided into three types:the Tienshan type,the Tethys type and the Gondwana type.Based on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas,this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction,providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of Gondwana.The results indicate that the North Qiangtang,South Qiangtang,Simao,Baoshan and Tengchong terranes,as well as the Himalaya Tethys Zone and the South China Block have affinities with the Indian Block,while the Lhasa Terrane has affinities with the Australian Block,and may be located between the South China and Australian blocks.In the Emsian(Early Devonian),the South China Block separated from the northern margin of Gondwana,a process that was accompanied by the opening of the Jinshajiang-Ailaoshan Ocean.In the Middle Devonian,the mid-oceanic ridge of the Paleo-Tethys Ocean expanded rapidly,corresponding with a global sea-level rise,the widespread development of carbonate platforms and nadir values of Devonian seawater strontium isotopes.By the Late Devonian,the Paleo-Tethys Ocean had reached a considerable size,leading to abundant occurrences of Upper Devonian radiolarian cherts in the Paleo-Tethys suture zones. 展开更多
关键词 DEVONIAN Paleo-Tethys Ocean Integrative stratigraphy Biotas Provenance Analysis PALEOGEOGRAPHY
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Middle Devonian ostracods from Jiwozhai patch reef(Dushan,Guizhou Province,South China):Biostratigraphic and palaeoecological implication
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作者 Jun-Jun Song Jia-Yuan Huang +4 位作者 wen guo Kun Liang Yu-Cong Sun Zhi-Hong Wang wen-Kun Qie 《Journal of Palaeogeography》 SCIE CSCD 2024年第3期581-593,共13页
The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figur... The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian. 展开更多
关键词 OSTRACODS GIVETIAN Jiwozhai patch reef Dushan PALAEOECOLOGY
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A bioactive nanocomposite integrated specific TAMs target and synergistic TAMs repolarization for effective cancer immunotherapy
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作者 Wei Gu wen guo +6 位作者 Zhishuang Ren Yimeng Zhang Meiqi Han Qinfu Zhao Yikun Gao Yuling Mao Siling Wang 《Bioactive Materials》 SCIE CSCD 2024年第8期472-485,共14页
Reactive oxygen species(ROS)generated from photosensitizers exhibit great potential for repolarizing immunosuppressive tumor-associated macrophages(TAMs)toward the anti-tumor M1 phenotype,representing a promising canc... Reactive oxygen species(ROS)generated from photosensitizers exhibit great potential for repolarizing immunosuppressive tumor-associated macrophages(TAMs)toward the anti-tumor M1 phenotype,representing a promising cancer immunotherapy strategy.Nevertheless,their effectiveness in eliminating solid tumors is generally limited by the instability and inadequate TAMs-specific targeting of photosensitizers.Here,a novel core-shell integrated nano platform is proposed to achieve a coordinated strategy of repolarizing TAMs for potentiating cancer immunotherapy.Colloidal mesoporous silica nanoparticles(CMSN)are fabricated to encapsulate photosensitizer-Indocyanine Green(ICG)to improve their stability.Then ginseng-derived exosome(GsE)was coated on the surface of ICG/CMSN for targeting TAMs,as well as repolarizing TAMs concurrently,named ICG/CMSN@GsE.As expected,with the synergism of ICG and GsE,ICG/CMSN@GsE exhibited better stability,mild generation of ROS,favorable specificity toward M2-like macrophages,enhancing drug retention in tumors and superior TAMs repolarization potency,then exerted a potent antitumor effect.In vivo,experiment results also confirm the synergistic suppression of tumor growth accompanied by the increased presence of anti-tumor M1-like macrophages and maximal tumor damage.Taken together,by integrating the superiorities of TAMs targeting specificity and synergistic TAMs repolarization effect into a single nanoplatform,ICG/CMSN@GsE can readily serve as a safe and high-performance nanoplatform for enhanced cancer immunotherapy. 展开更多
关键词 Ginseng-derived exosome Colloidal mesoporous silica nanoparticles Tumor-associated macrophages TAMs-specific targeting delivery Repolarizing TAMs
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