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| 1 | Towards 6G wireless communication networks:vision,enabling technologies,and new paradigm shifts显示文摘The fifth generation(5G)wireless communication networks are being deployed worldwide from 2020 and more capabilities are in the process of being standardized,such as mass connectivity,ultra-reliability,and guaranteed low latency.However,5G will not meet all requirements of the future in 2030 and beyond,and sixth generation(6G)wireless communication networks are expected to provide global coverage,enhanced spectral/energy/cost efficiency,better intelligence level and security,etc.To meet these requirements,6G networks will rely on new enabling technologies,i.e.,air interface and transmission technologies and novel network architecture,such as waveform design,multiple access,channel coding schemes,multi-antenna technologies,network slicing,cell-free architecture,and cloud/fog/edge computing.Our vision on 6G is that it will have four new paradigm shifts.First,to satisfy the requirement of global coverage,6G will not be limited to terrestrial communication networks,which will need to be complemented with non-terrestrial networks such as satellite and unmanned aerial vehicle(UAV)communication networks,thus achieving a space-airground-sea integrated communication network.Second,all spectra will be fully explored to further increase data rates and connection density,including the sub-6GHz,millimeter wave(mmWave),terahertz(THz),and optical frequency bands.Third,facing the big datasets generated by the use of extremely heterogeneous networks,diverse communication scenarios,large numbers of antennas,wide bandwidths,and new service requirements,6G networks will enable a new range of smart applications with the aid of artificial intelligence(AI)and big data technologies.Fourth,network security will have to be strengthened when developing 6G networks.This article provides a comprehensive survey of recent advances and future trends in these four aspects.Clearly,6G with additional technical requirements beyond those of 5G will enable faster and further communications to the extent that the boundary between physical and cyber worlds disappears. | Xiaohu YOU Cheng-Xiang WANG Jie HUANG Xiqi GAO Zaichen ZHANG Mao WANG Yongming HUANG Chuan ZHANG Yanxiang JIANG Jiaheng WANG Min ZHU Bin SHENG Dongming WANG Zhiwen PAN Pengcheng ZHU Yang YANG Zening LIU Ping ZHANG Xiaofeng TAO Shaoqian LI Zhi CHEN Xinying MA Chih-Lin I Shuangfeng HAN Ke LI Chengkang PAN Zhimin ZHENG Lajos HANZO Xuemin(Sherman)SHEN Yingjie Jay GUO Zhiguo DING Harald HAAS Wen TONG Peiying ZHU Ganghua YANG Jun WANG Erik GLARSSON Hien Quoc NGO Wei HONG Haiming WANG Debin HOU Jixin CHEN Zhe CHEN Zhangcheng HAO Geoffrey Ye LI Rahim TAFAZOLLI Yue GAO HVincent POOR Gerhard P.FETTWEIS Ying-Chang LIANG | 2021 | Science China(Information Sciences)2021，64，1： | 122 |
| 2 | Rural land use spatial allocation in the semiarid loess hilly area in China:Using a Particle Swarm Optimization model equipped with multi-objective optimization techniques显示文摘Semiarid loess hilly areas in China are enduring a series of environmental conflicts between urban expansion,cultivated land conservation,soil erosion and water shortage,and require land use allocation to reconcile these environmental conflicts.We argue that the optimized spatial allocation of rural land use can be achieved by a Particle Swarm Optimization (PSO) model in conjunction with multi-objective optimization techniques.Our study focuses on Yuzhong County of Gangsu Province in China,a typical catchment on the Loess Plateau,and proposes a land use spatial optimization model.The model maximizes land use suitability and spatial compactness based on a variety of constraints,e.g.optimal land use structure and restrictive areas,and employs an improved PSO algorithm equipped with a determinant initialization method and a dynamic weighted aggregation (DWA) method to obtain the optimized land use spatial pattern.The results suggest that (1) approximately 4% of land use should be reallocated and these changes would alleviate the environmental conflicts in the study area;(2) the major reshuffling is slope farmland and newly added construction and cultivated land,whereas the unchanged areas are largely forests and basic farmland;and (3) the PSO is capable of optimizing rural land use allocation,and the determinant initialization method and DWA can improve the performance of the PSO. | LIU YaoLin LIU DianFeng LIU YanFang HE JianHua JIAO LiMin CHEN YiYun HONG XiaoFeng | 2012 | Science China Earth Sciences2012，55，7： | 23 |
| 3 | TALEN-based generation of a cynomolgus monkey disease model for human microcephaly显示文摘基因在非人类的首领编辑可以为在人探索病原学和遗传上基于的神经病学的混乱的治疗学的策略导致珍贵模型。然而,仔细在人模仿病理学、行为的赤字的神经病学的混乱的一个猴子模型成功地还没被产生了。Microcephalin 1 (MCPH1 ) 在人的大脑,和智力迟钝伴随的 MCPH1 变化原因头小畸型的进化被含有。这里,我们产生了用抄写带 biallelic MCPH1 变化的一只 cynomolgus 猴子(Macaca fascicularis ) 像使活跃之物的受动器核酸酶。猴子概括了大多数在病人观察的重要临床的特征,包括在头圆周,早熟的染色体冷凝作用(PCC ) ,语料库 callosum 的发育不全和上面的手足 spasticity 的显著减小。而且,在变异的真皮的成纤维细胞的 MCPH1 的 overexpression 救了 PCC 症候群。这个猴子模型可以帮助我们阐明在人的头小畸型并且更好的致病的 MCPH1 的角色在首领大脑尺寸的进化理解这蛋白质的功能。 | Qiong Ke Weiqiang Li Xingqiang Lai Hong Chen Lihua Huang Zhuang Kang Kai Li Jie Ren Xiaofeng Lin Haiqing Zheng Weijun Huang Yunhan Ma Dongdong Xu Zheng Chen Xinming Song Xinyi Lin Min Zhuang Tao Wang Fengfeng Zhuang Jianzhong Xi Frank Fuxiang Mao Huimin Xia Bruce T Lahn Qi Zhou Shihua Yang Andy Peng Xiang | 2016 | Cell Research2016，26，9： | 13 |
| 4 | Neuroprotective effects of Ginkgo biloba extract and GinkgoUde B against oxygen-glucose deprivation/reoxygenation and glucose injury in a new in vitro multicellular network model显示文摘 | Xiaohan Yang Tiezheng Zheng Hao Hong Nan Cai Xiaofeng Zhou Changkai Sun Liying Wu Shuhong Liu Yongqi Zhao Lingling Zhu Ming Fan Xuezhong Zhou Fengxie Jin | 2018 | Frontiers of Medicine2018，12，3： | 12 |
| 5 | Tomographic imaging of P wave velocity structure beneath the region around Beijing显示文摘The three-dimension crustal and upper mantle structures in the region around Beijing were studied by seismic tomography. We used the P wave arrival times from local and teleseismic events. These events were recorded by 250 stations of the North China Seismic Array and 108 stations of the Beijing Telemetry Seismic Network. 118 869 P wave arrivals from 10 285 local events and 12 189 P wave arrivals from 107 teleseismic events were used in the inversion. We obtained the 3-D P wave velocity structure of the crust and upper mantle with the horizontal resolution of 0.3° in the studied region. The tomographic imaging shows the remarkably heterogeneous velocity variation. The velocity anomalies are in well agreement with the geological structure in the shallow crust. The different relationships between seismic activities and velocity anomalies may imply the different seismogenic structure and mechanism. Beneath the Moho under Taihangshan mountain and Yanshan mountain,we found the high velocity anomalies deep to 120 km and 200 km,respectively. The deep high velocity zone may be explained by the existence of the mountain root under Yanshan mountain. The high velocity anomalies in the upper mantle of North China basin may be the relics of the de-rooting from the former craton mantle lithosphere. | Zhifeng Ding Xiaofeng Zhou Yan Wu Guiyin Li Hong Zhang | 2009 | Earthquake Science2009，22，4： | 10 |
| 6 | Nutritional compositions of various potato noodles:Comparative analysis显示文摘In this study,three kinds of noodles,wheat,Shepody potato and Atlantic potato noodles,were produced with blended powder consisting of wheat flour and certain amounts of various potato flours.In order to investigate the effects of potato flour on the nutritional characteristics of noodles,the nutrient compositions of four types of noodles were analyzed:fresh noodle,dried noodle,fresh noodle after boiling,and dried noodle after boiling.Results showed that the contents of protein,crude fiber,total ash,reducing sugar,vitamin B1,vitamin B2,vitamin B3,vitamin C,most mineral elements,dietary fiber,and amino acids in potato noodles were higher than those in wheat noodles.Furthermore,drying and boiling could decrease the contents of vitamin B1,vitamin B3,and mineral elements in noodles,but the nutrient contents in potato noodles remained higher than those in wheat noodles.The comprehensive nutritional values of noodles were evaluated using the index of nutritional quality,the results showed that the nutritional value of Shepody potato noodles was the highest,followed by that of Atlantic potato noodles and then wheat noodles. | Xu Fen Hu Honghai Dai Xiaofeng Liu Qiannan Huang Yanjie Zhang Hong | 2017 | International Journal of Agricultural and Biological Engineering2017，10，1： | 9 |
| 7 | Phylogenetic and genetic characterization of a 2017 clinical isolate of H7N9 virus in Guangzhou,China during the fifth epidemic wave显示文摘Pathogenic H7N9 influenza viruses continue to pose a public health concern. The H7N9 virus has caused five outbreak waves of human infections in China since 2013. In the present study, a novel H7N9 strain(A/Guangdong/8 H324/2017) was isolated from a female patient with severe respiratory illness during the fifth wave of the 2017 H7N9 epidemic. Phylogenetic analysis showed that the H7N9 viruses collected during the fifth wave belong to two different lineages: the Pearl River Delta lineage and the Yangtze River Delta lineage. The novel isolate is closely related to the Pearl River Delta H7N9 viruses, which were isolated from patients in Guangdong Province. The novel H7N9 isolate has an insertion of three basic amino acids in the cleavage site of hemagglutinin(HA), which may enhance virulence in poultry. The 2017 isolate also possesses an R292 K substitution in the neuraminidase(NA)protein, which confers oseltamivir resistance. This study highlights the pandemic potential of the novel H7N9 virus in mammals;thus, future characterization and surveillance is warranted. | Yongqiang Deng Chunlin Li Jianfeng Han Yingfen Wen Jian Wang Wenxing Hong Xiaofeng Li Zhongyu Liu Qing Ye Jing Li Changshuai Zhou Lei Yu Chengfeng Qin Fuchun Zhang Tao Jiang | 2017 | Science China(Life Sciences)2017，60，12： | 9 |
| 8 | Mechanisms underlying attenuation of apoptosis of cortical neurons in the hypoxic brain by flavonoids from the stems and leaves of Scutellaria baicalensis Georgi显示文摘Flavonoids from the stems and leaves of Scutellaria baicalensis Georgi, an antioxidant, markedly improve memory impairments and neuronal injuries. In the present study, primary cortical neurons of rats were exposed to potassium cyanide to establish a model of in vitro neural cell apoptosis. Inhibition of apoptosis by flavonoids from the stems and leaves of Scutellaria baicalensis Georgi at concentrations of 18.98, 37.36, and 75.92 μg/mL was detected using this model. These flavonoids dramatically increased cell survival, inhibited cell apoptosis and excessive production of malondialdehyde, and increased the activities of superoxide dismutase, glutathione peroxidase, and Na+-K+-ATPase in primary cortical neurons exposed to potassium cyanide. The flavonoids from the stems and leaves of Scutellaria baicalensis Georgi were originally found to have a polyhydric structure and to protect against cerebral hypoxia in in vitro and in vivo models, including hypoxia induced by potassium cyanide or cerebral ischemia. The present study suggests that flavonoids from the stems and leaves of Scutellaria baicalensis Georgi exert neuroprotective effects via modulation of oxidative stress, such as malondialdehyde, superoxide dismutase, glutathione peroxidase and Na+-K+-ATPase disorders induced by potassium cyanide. | Guangxin Miao Hongxiang Zhao Ke Guo Jianjun Cheng Shufeng Zhang Xiaofeng Zhang Zhenling Cai Hong Miao Yazhen Shang | 2014 | Neural Regeneration Research2014，9，17： | 8 |
| 9 | Abiogenic hydrocarbons in commercial gases from the Songliao Basin,China显示文摘This paper discusses the kinetic fractionation, composition and distribution characteristics of carbon and hydrogen isotopes for various alkane gases formed in different environments, by different mecha- nisms and from different sources in nature. It is demonstrated that the biodegradation or thermode- gradation of complex high-molecule sedimentary organic material can form microbial gas or thermogenic gas. The δ 13C1 value ranges from -110‰ to -50‰ for microbial gases but from -50‰ to -35‰ (even heavier) for thermogenic gases. Controlled by the kinetic isotope fractionation, both microbial and thermogenic gases have δ 13C and δ D values characterized by normal distribution, i.e. δ 13C1< δ 13C2< δ 13C3< δ 13C4 and δ DCH4< δ DC2H6< δ DC3H8<δ DC4H10, and by a positive correlation between the δ 13C and δ D values. Simple carbonbearing molecules (CH4, CO and CO2) can form abiogenic alkane gases via polymerization in the abiological chemical process in nature, with δ 13C1 heavier than -30‰. Moreover, controlled by the kinetic isotope fractionation, abiogenic alkane gases are characterized by a reverse distribution of δ 13C values and a normal trend of δ D values, namely δ 13C1> δ 13C2> δ 13C3> δ 13C4 and δ DCH4<δ DC2H6< δ DC3H8< δ DC4H10. The δ 13C values and δ D values are negatively correlated. Natural gases from 26 commercial gas wells distributed in the Xujiaweizi and Yingshan-Miaotaizi faulted depressions in the Songliao Basin, China, show δ13C1 values ranging from -30.5‰ to -16.7‰ with a very narrow δ D range between -203‰―-196‰. These gases are characterized by a reverse distribution of δ 13C values but a normal distribution of δ D values, and a negative correlation between their δ 13C and δ D values, indicating an abiological origin. The present study has revealed that abiogenic hydrocarbons not only exist in nature but also can make significant contribution to commercial gas reserviors. It is estimated that the reserve volume of alkane gases with abiogenic characteristics in these 26 gas wells in the Songliao Basin is over 500×108 m3. The prospecting practice in the Songliao Basin has demonstrated that abiogenic alkane gases are of a promising resource, and it provides an example for the investigation of and search for abiogenic commercial natural gases worldwide. | WANG XianBin GUO ZhanQian TUO JinCai GUO HongYan LI ZhenXi ZHUO ShengGuang JIANG HongLiang ZENG LongWei ZHANG MingJie WANG LianSheng LIU ChunXue YAN Hong LI LiWu ZHOU XiaoFeng WANG YongLi YANG Hui WANG Guang | 2009 | Science China Earth Sciences2009，52，2： | 6 |
| 10 | Recent Development in X-Ray Imaging Technology:Future and Challenges显示文摘X-ray imaging is a low-cost,powerful technology that has been extensively used in medical diagnosis and industrial nondestructive inspection.The ability of X-rays to penetrate through the body presents great advances for noninvasive imaging of its internal structure.In particular,the technological importance of X-ray imaging has led to the rapid development of highperformance X-ray detectors and the associated imaging applications.Here,we present an overview of the recent development of X-ray imaging-related technologies since the discovery of X-rays in the 1890s and discuss the fundamental mechanism of diverse X-ray imaging instruments,as well as their advantages and disadvantages on X-ray imaging performance.We also highlight various applications of advanced X-ray imaging in a diversity of fields.We further discuss future research directions and challenges in developing advanced next-generation materials that are crucial to the fabrication of flexible,low-dose,highresolution X-ray imaging detectors. | Xiangyu Ou Xue Chen Xianning Xu Lili Xie Xiaofeng Chen Zhongzhu Hong Hua Bai Xiaowang Liu Qiushui Chen Lin Li Huanghao Yang | 2021 | Research2021，，1： | 5 |
| 11 | Umbilical cord mesenchymal stem cell transplantation for the treatment of Duchenne muscular dystrophy显示文摘Due to their relative abundance,stable biological properties and excellent reproductive activity,umbilical cord mesenchymal stem cells have previously been utilized for the treatment of Duchenne muscular dystrophy,which is a muscular atrophy disease.Three patients who were clinically and pathologically diagnosed with Duchenne muscular dystrophy were transplanted with umbilical cord mesenchymal stem cells by intravenous infusion,in combination with multi-point intramuscular injection.They were followed up for 12 months after cell transplantation.Results showed that clinical symptoms significantly improved,daily living activity and muscle strength were enhanced,the sero-enzyme,electromyogram,and MRI scans showed improvement,and dystrophin was expressed in the muscle cell membrane.Hematoxylin-eosin staining of a muscle biopsy revealed that muscle fibers were well arranged,fibrous degeneration was alleviated,and fat infiltration was improved.These pieces of evidence suggest that umbilical cord mesenchymal stem cell transplantation can be considered as a new regimen for Duchenne muscular dystrophy. | Xiaofeng Yang Yifeng Xu Naiwu Lu Yibin Zhang Hongmei Wang Xin Lu Jiping Cui JinxuZhou Hong Shan Yanxiang Wu Xinping Liu | 2011 | Neural Regeneration Research2011，6，10： | 4 |
| 12 | An Optimized Vertical Handoff Algorithm Based on Markov Process in Vehicle Heterogeneous Network显示文摘In order to solve the problem the existing vertical handoff algorithms of vehicle heterogeneous wireless network do not consider the diversification of network's status, an optimized vertical handoff algorithm based on markov process is proposed and discussed in this paper. This algorithm takes into account that the status transformation of available network will affect the quality of service(Qo S) of vehicle terminal's communication service. Firstly, Markov process is used to predict the transformation of wireless network's status after the decision via transition probability. Then the weights of evaluating parameters will be determined by fuzzy logic method. Finally, by comparing the total incomes of each wireless network, including handoff decision incomes, handoff execution incomes and communication service incomes after handoff, the optimal network to handoff will be selected. Simulation results show that: the algorithm proposed, compared to the existing algorithm, is able to receive a higher level of load balancing and effectively improves the average blocking rate, packet loss rate and ping-pang effect. | MA Bin DENG Hong XIE Xianzhong LIAO Xiaofeng | 2015 | China Communications2015，12，4： | 4 |
| 13 | A versatile photodetector assisted by photovoltaic and bolometric effects显示文摘The advent of low-dimensional materials with peculiar structure and superb band properties provides a new canonical form for the development of photodetectors.However,the limited exploitation of basic properties makes it difficult for devices to stand out.Here,we demonstrate a hybrid heterostructure with ultrathin vanadium dioxide film and molybdenum ditelluride nanoflake.Vanadium dioxide is a classical semiconductor with a narrow bandgap,a high temperature coefficient of resistance,and phase transformation.Molybdenum ditelluride,a typical two-dimensional material,is often used to construct optoelectronic devices.The heterostructure can realize three different functional modes:(i)the p-n junction exhibits ultrasensitive detection(450 nm-2μm)with a dark current down to 0.2 pA and a response time of 17μs,(ii)the Schottky junction works stably under extreme conditions such as a high temperature of 400 K,and(iii)the bolometer shows ultrabroad spectrum detection exceeding 10μm.The flexible switching between the three modes makes the heterostructure a potential candidate for next-generation photodetectors from visible to longwave infrared radiation(LWIR).This type of photodetector combines versatile detection modes,shedding light on the hybrid application of novel and traditional materials,and is a prototype of advanced optoelectronic devices. | Wei Jiang Tan Zheng Binmin Wu Hanxue Jiao Xudong Wang Yan Chen Xiaoyu Zhang Meng Peng Hailu Wang Tie Lin Hong Shen Jun Ge Weida Hu Xiaofeng Xu Xiangjian Meng Junhao Chu Jianlu Wang | 2020 | Light(Science & Applications)2020，9，1： | 3 |
| 14 | Human ZCCHC12 activates AP-1 and CREB signaling as a transcriptional co-activator显示文摘包含 12 基因(ZCCHC12 ) 的老鼠锌手指 CCHC 领域作为骨头的 transcriptional 激活剂被识别了发信号的形态基因的蛋白质(BMP ) ,和人的 ZCCHC12 被报导与 non-syndromic X 连接智力迟钝(NS-XLMR ) 有关。然而,的细节人的 ZCCHC12 在 NS-XLMR 包含仍然保持不清楚。在这研究,我们在为原子本地化负责的人的 ZCCHC12 蛋白质的中间识别了一个新奇原子本地化信号(NLS ) 。多重织物的北污点分析显示 ZCCHC12 高度在人的大脑被表示。而且,在 situ,杂交证明 ZCCHC12 明确地在老鼠 E10.5 胚胎的前脑,中脑,和间脑区域的 neuroepithelium 被表示。酶记者试金证明 ZCCHC12 作为激活剂提高了使活跃之物蛋白质 1 的 transcriptional 活动(AP-1 ) 和营地反应元素绑定蛋白质(CREB ) 。在结论,我们在 ZCCHC12 识别了新 NLS 并且弄明白 ZCCHC12 作为 AP-1 和 CREB 的 transcriptional 激活剂工作。 | Hong Li Qian Liu Xiang Hu Du Feng Shuanglin Xiang Zhicheng He Xingwang Hu Jianlin Zhou Xiaofeng Ding Chang Zhou Jian Zhang | 2009 | Acta Biochimica et Biophysica Sinica2009，41，7： | 3 |
| 15 | Preparation of Mg,N-co-doped lignin adsorbents for enhanced selectivity and high adsorption capacity of As(Ⅴ) from wastewater显示文摘Among various environmental problems,water pollution has drawn more and more attention.To develop an adsorbent with enhanced selectivity and high capacity for As(V)oxyanion,a novel lignin-based adsorbent was prepared by doping with N and modifying with Mg^(2+),using thiethylenetetramine(TETA)and MgCl_(2) as the source of N and Mg^(2+),respectively.N-doped lignin(NL)shows a high selectivity for As(Ⅴ),which is further enhanced by modifying with Mg^(2+)(MNL).MNL shows an excellent reusability.The adsorption isotherms and kinetics of MNL for As(Ⅴ)follow Langmuir isotherms model and pseudo-second-order kinetics model,respectively.The adsorption of MNL for As(Ⅴ)achieved a maximum adsorption capacity of 687.46 mg g^(−1) and the equilibrium was established within 30 min.This study offers a novel idea on the recycle of the waste of paper industry and provides a new technology for As(Ⅴ)adsorption from wastewater. | Xiaofeng Shi Junmao Hong Chao Wang Sifang Kong Junhua Li Duo Pan Jing Lin Qinglong Jiang Zhanhu Guo | 2021 | Particuology2021，19，5： | 2 |
| 16 | Effect of adjuvant therapy with electroacupuncture on bone turnover markers and interleukin 17 in patients with rheumatoid arthritis显示文摘OBJECTIVE: To evaluate the effect of electroacupuncture as an adjuvant treatment with first-line medications on bone metabolism biomarkers and interleukin-17(IL-17) in the peripheral blood of patients with rheumatoid arthritis(RA).METHODS: Sixty RA patients were randomized into three groups. The control group was treated with methotrexate plus leflunomide(MTX + LEF),the acupuncture group was treated with simple needling plus MTX + LEF, and the patients in the electroacupuncture(EA) group were treated with EA plus MTX + LEF. EA or acupuncture was applied every other day for a total of 10 times over a treatment period of 8 weeks.RESULTS: In all three treatment groups, serum levels of the bone metabolism markers PICP, N-MID,and B-ALP were elevated and the concentrations of the inflammatory markers β-CTx, IL-17, CRP, and TRACP-5b were reduced after treatment. These differences were significant for the EA group but not the other groups(P < 0.05).CONCLUSION: EA could effectively reduce the suffering and improve the quality of life of RA patients. It is a promising adjuvant therapy for enhancing the effectiveness of clinical therapeutics. | Zeng Chuang Bai Xuejing Qin Heping Wang Hong Rong Xiaofeng Yan Jin | 2019 | Journal of Traditional Chinese Medicine2019，39，4： | 2 |
| 17 | An L-band HTS duplexer with improved performance显示文摘An L-band HTS duplexer with improved performance for communication applications has been developed.This is an improved version of the duplexer previously developed by our group.The duplexer was composed of a T-junction and two channels.Each channel has a 10-pole quasi-elliptic function bandpass HTS filter with a bandwidth of 27 MHz,and center frequencies at 1200 MHz and 1260 MHz.To achieve higher performance,especially a good balance between selectivity and flat group delay,the two pairs of transmission zeros from the two filters were reassigned so that one pair is used for high selectivity and the other for flat group delay.To reduce the influence of parasitical coupling,new coupling structures were developed in the simulation process.The duplexer was fabricated on a 2 inch diameter,0.5 mm thick LaAlO3 wafer with a double-sided YBCO film.The measured results showed a very high performance:a mid-band insertion loss of 0.2 dB,a return loss better than-14 dB,a shape factor better than 1.4:1,an out-of-band rejection of better than 70 dB in a wide frequency range up to 3 GHz and excellent isolation(higher than 80 dB) between the two channels.In addition,the frequency band 5 ns group delay variation is over 10.5 MHz(38.7% of 1 dB bandwidth). | Jia Wang Qiang Zhang Bin Cui Jin Guo YongBo Bian XiaoFeng He ChunGuang Li XueQiang Zhang Hong Li WuXia Li et al. | 2010 | Chinese Science Bulletin2010，55，31： | 2 |
| 18 | Identification of secondary organic aerosols based on aerosol mass spectrometry显示文摘Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so far.Due to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol study.This study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) analysis.Major sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer measurement.It showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic mass.Compared with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary pollutants.The ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the atmosphere.The most effective period for SOA formation was from 9 am~3 pm since the SOA/BC ratio increased by 122% during this period.This study provides a new technical method and a new idea for SOA investigation. | HUANG XiaoFeng 1,ZHAO QianBiao 1,2,HE LingYan 1,HU Min 2,BIAN QiJing 3,XUE Lian 1 & ZHANG YuanHang 2 1 Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy,Peking University Shenzhen Graduate School,Shenzhen 518055,China 2 State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 3 Division of Environment,Hong Kong University of Science & Technology,Hong Kong,China | 2010 | Science China Chemistry2010，53，12： | 2 |
| 19 | Correlation of obstructive sleep apnea hypopnea syndrome with metabolic syndrome in snorers显示文摘Though obstructive sleep apnea hypopnea syndrome(OSAHS) and metabolic syndrome(MS) are correlated;the contributing factors for the occurrence of MS in Chinese snorers remain largely undefined.We aimed to investigate the associated pathogenesis of coexistence of OSAHS and MS in Chinese snorers.A total of 144 Chinese habitual snorers were divided into 3 groups,the control group(simple snorers)(n = 36),the mild OSAHS group(n= 52)and the moderate-to-severe OSAHS group(n = 56).The incidence of MS in the moderate-to-severe OSAHS group(26.8%) was significantly higher than that in the control group(8.3%),the mild OSAHS group(11.1%) and all the OSAHS patients(19.45%)(all P < 0.05).Homeostatic model assessment(HOMA) index and proinsulin(PI) were negatively correlated with nocturnal meanSpO_2 and miniSpO_2.Meanwhile,nocturnal SpO_2 were negatively correlated with body mass index,waist and neck circumferences and diastolic blood pressure,but positively correlated with total cholesterol and high-density lipoprotein cholesterol.The study indicated that in Chinese snorers,moderate-to-severe OSAHS was closely associated with MS via nocturnal hypoxemia. | Qun Zhang Xiaofeng Zhang Mengmeng Zhao Hanpeng Huang Ning Ding Xilong Zhang Hong Wang | 2014 | The Journal of Biomedical Research2014，28，3： | 2 |
| 20 | Experimental Research on Structural Behaviors of Glulam I-Beam with a Special-Shaped Section显示文摘In order to enhance the bearing capacity of structural components,save materials,and reduce cost,a glued laminated timber(glulam)I-beam that is theoretically suitable for engineering application was proposed.In this study,18 glulam specimens were fabricated using larch dimension lumber and resorcinol-formaldehyde resin.Four-point bending tests were carried out to compare the ultimate bearing capacity,strain,and deflection of various specimens.The results showed that:(1)The typical failure mode at bending is the web shear failure parallel to grain.Before the failure,cracks and sounds appear at the beam web,which represent the sudden brittle failure.(2)The cross-sectional strain of glulam beam changed linearly with the beam height,indicating that the plane section assumption was basically established.(3)Stiffener could improve the initial flexural stiffness of glulam beam,which experiences an increase of 28.21%.Larger the shear span ratio,smaller the initial flexural stiffness.The initial flexural stiffness improves by 10-23.5%with the increase in the thickness of the lower flange.(4)The effects of stiffener and shear-span ratio on shear strength are relatively significant.After the stiffeners are set at the support and the loading point in pairs,the shear strength of the glulam beam increases by 15.05%averagely.With the increase in the shear-span ratio,the shearing strength of the glulam I-beam gradually reduces.The equation of the shearing strength with the shear span ratio is obtained,which is shown by high fitting precision.(5)The shear strength correlation,as proposed by Soltis and Rammer,is suitable not only for rectangular beams,but also for glulam I-beams. | Ruyuan Yang Chaokun Hong Xiaofeng Zhang Quan Yuan Youfu Sun | 2020 | Journal of Renewable Materials2020，8，2： | 2 |
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