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| 1 | Altered trends in carbon uptake in China’s terrestrial ecosystems under the enhanced summer monsoon and warming hiatus显示文摘The carbon budgets in terrestrial ecosystems in China are strongly coupled with climate changes.Over the past decade,China has experienced dramatic climate changes characterized by enhanced summer monsoon and decelerated warming.However,the changes in the trends of terrestrial net ecosystem production(NEP)in China under climate changes are not well documented.Here,we used three ecosystem models to simulate the spatiotemporal variations in China's NEP during 1982–2010 and quantify the contribution of the strengthened summer monsoon and warming hiatus to the NEP variations in four distinct climatic regions of the country.Our results revealed a decadal-scale shift in NEP from a downtrend of–5.95 Tg C/yr^2(reduced sink)during 1982–2000 to an uptrend of 14.22 Tg C/yr^2(enhanced sink)during 2000–10.This shift was essentially induced by the strengthened summer monsoon,which stimulated carbon uptake,and the warming hiatus,which lessened the decrease in the NEP trend.Compared to the contribution of 56.3%by the climate effect,atmospheric CO2 concentration and nitrogen deposition had relatively small contributions(8.6 and 11.3%,respectively)to the shift.In conclusion,within the context of the global-warming hiatus,the strengthening of the summer monsoon is a critical climate factor that enhances carbon uptake in China due to the asymmetric response of photosynthesis and respiration.Our study not only revealed the shift in ecosystem carbon sequestration in China in recent decades,but also provides some insight for understanding ecosystem carbon dynamics in other monsoonal areas. | Honglin He Shaoqiang Wang Li Zhang Junbang Wang Xiaoli Ren Lei Zhou Shilong Piao Hao Yan Weimin Ju Fengxue Gu Shiyong Yu Yuanhe Yang Miaomiao Wang Zhongen Niu Rcmg Ge Huimin Yan Mei Huang Guoyi Zhou Yongfei Bai Zongqiang Xie Zhiyao Tang Bingfang Wu Leiming Zhang Nianpeng He Qiufeng Wang Guirui Yu | 2019 | National Science Review2019，6，3： | 24 |
| 2 | The impacts of climate extremes on the terrestrial carbon cycle:A review显示文摘The increased frequency of climate extremes in recent years has profoundly affected terrestrial ecosystem functions and the welfare of human society. The carbon cycle is a key process of terrestrial ecosystem changes. Therefore, a better understanding and assessment of the impacts of climate extremes on the terrestrial carbon cycle could provide an important scientific basis to facilitate the mitigation and adaption of our society to climate change. In this paper, we systematically review the impacts of climate extremes(e.g. drought, extreme precipitation, extreme hot and extreme cold) on terrestrial ecosystems and their mechanisms. Existing studies have suggested that drought is one of the most important stressors on the terrestrial carbon sink, and that it can inhibit both ecosystem productivity and respiration. Because ecosystem productivity is usually more sensitive to drought than respiration, drought can significantly reduce the strength of terrestrial ecosystem carbon sinks and even turn them into carbon sources. Large inter-model variations have been found in the simulations of drought-induced changes in the carbon cycle, suggesting the existence of a large gap in current understanding of the mechanisms behind the responses of ecosystem carbon balance to drought, especially for tropical vegetation. The effects of extreme precipitation on the carbon cycle vary across different regions. In general, extreme precipitation enhances carbon accumulation in arid ecosystems, but restrains carbon sequestration in moist ecosystems. However, current knowledge on the indirect effects of extreme precipitation on the carbon cycle through regulating processes such as soil carbon lateral transportation and nutrient loss is still limited. This knowledge gap has caused large uncertainties in assessing the total carbon cycle impact of extreme precipitation. Extreme hot and extreme cold can affect the terrestrial carbon cycle through various ecosystem processes. Note that the severity of such climate extremes depends greatly on their timing, which needs to be investigated thoroughly in future studies. In light of current knowledge and gaps in the understanding of how extreme climates affect the terrestrial carbon cycle, we strongly recommend that future studies should place more attention on the long-term impacts and on the driving mechanisms at different time scales.Studies based on multi-source data, methods and across multiple spatial-temporal scales, are also necessary to better characterize the response of terrestrial ecosystems to climate extremes. | Shilong PIAO Xinping ZHANG Anping CHEN Qiang LIU Xu LIAN Xuhui WANG Shushi PENG Xiuchen WU | 2019 | Science China Earth Sciences2019，62，10： | 16 |
| 3 | Plant phenological responses to climate change on the Tibetan Plateau: research status and challenges显示文摘Phenology studies the cycle of events in nature that are initiated and driven by an annually recurring environment. Plant phenology is expected to be one of the most sensitive and easily observable natural indicators of climate change. On the Tibetan Plateau(TP), an accelerated warming since the mid-1980 s has resulted in signiicant environmental changes. hese new conditions are accompanied by phenological changes that are characterized by considerable spatiotemporal heterogeneity. Satellite remote sensing observed widespread advance in the start of the plant growing season across the plateau during the 1980 s and 1990 s but substantial delay over 2000–2011 in the southwest although it continued to advance in the northeast regions of the TP. Both observational studies and controlled experiments have revealed, to some extent, the positive role of higher preseason temperature and even more precipitation in advancing the leaf onset and irst lowering date of the TP. However, a number of rarely visited research issues that are essential for understanding the role of phenology in ecosystem responses and feedback processes to climate change remain to be solved. Our review recommends that addressing the following questions should be a high priority. How did other phenological events change, such as lowering and fruiting phenology? What are the inluences from environmental changes other than temperature and precipitation, including human activities such as grazing? What are the genetic and physiological bases of plants phenological responses?How does phenological change inluence ecosystem structure and function at diferent scales and feedback to the climate system? Investigating these research questions requires, irst of all, new data of the associated environmental variables, and consistent and reliable phenological observation using diferent methodologies(i.e. in situ observations and remote sensing). | Miaogen Shen Shilong Piao Tsechoe Dorji Qiang Liu Nan Cong Xiaoqiu Chen Shuai An Shiping Wang Tao Wang Gengxin Zhang | 2015 | National Science Review2015，2，4： | 13 |
| 4 | Photonics-based radar with balanced I/Q de-chirping for interference-suppressed high-resolution detection and imaging显示文摘Photonics-based radar with a photonic de-chirp receiver has the advantages of broadband operation and real-time signal processing, but it suffers from interference from image frequencies and other undesired frequency-mixing components, due to single-channel real-valued photonic frequency mixing. In this paper, we propose a photonicsbased radar with a photonic frequency-doubling transmitter and a balanced in-phase and quadrature(I/Q)de-chirp receiver. This radar transmits broadband linearly frequency-modulated signals generated by photonic frequency doubling and performs I/Q de-chirping of the radar echoes based on a balanced photonic I/Q frequency mixer, which is realized by applying a 90° optical hybrid followed by balanced photodetectors. The proposed radar has a high range resolution because of the large operation bandwidth and achieves interference-free detection by suppressing the image frequencies and other undesired frequency-mixing components. In the experiment, a photonics-based K-band radar with a bandwidth of 8 GHz is demonstrated. The balanced I/Q de-chirping receiver achieves an image-rejection ratio of over 30 dB and successfully eliminates the interference due to the baseband envelope and the frequency mixing between radar echoes of different targets. In addition, the desired dechirped signal power is also enhanced with balanced detection. Based on the established photonics-based radar,inverse synthetic aperture radar imaging is also implemented, through which the advantages of the proposed radar are verified. | XINGWEI YE FANGZHENG ZHANG YUE YANG SHILONG PAN | 2019 | Photonics Research2019，7，3： | 9 |
| 5 | Dynamical characteristics of software trustworthiness and their evolutionary complexity显示文摘Developing trusted softwares has become an important trend and a natural choice in the development of software technology and applications, and software trustworthiness modeling has become a prerequisite and necessary means. To discuss and explain the basic scientific problems in software trustworthiness and to establish theoretical foundations for software trustworthiness measurement, combining the ideas of dynamical system study, this paper studies evolutionary laws of software trustworthiness and the dynamical mechanism under the effect of various internal and external factors, and proposes dynamical models for software trustworthiness, thus, software trustworthiness can be considered as the statistical characteristics of behaviors of software systems in the dynamical and open environment. By analyzing two simple examples, the paper explains the relationship between the limit evolutionary behaviors of software trustworthiness attributes and dynamical system characteristics, and interprets the dynamical characteristics of software trustworthiness and their evolutionary complexity. | ZHENG ZhiMing MA ShiLong LI Wei WEI Wei JIANG Xin ZHANG ZhanLi GUO BingHui | 2009 | Science in China(Series F)2009，52，8： | 8 |
| 6 | Chemical and boron isotopic compositions of tourmaline in the Longtoushan hydrothermal gold deposit, Guangxi, China:implications for gold mineralization显示文摘The Longtoushan hydrothermal gold deposit is located in the southwestern region of the Dayaoshan Uplift.Tourmaline is widespread in the Longtoushan gold deposit and is mainly distributed in the rhyolite porphyry and associated cryptoexplosive breccia. The spatial distribution of tourmaline enrichment is similar to that of the gold orebody. Feldspar has been largely replaced by tourmaline in the rhyolite porphyry and cryptoexplosive breccia.Electron microprobe analysis revealed that tourmalines in the Longtoushan deposit belong mainly to the alkali group and partly to the X-vacant group; they mostly fell in the schorl-dravite series field. Two distinct sets of dominant substitutions were observed: MgFe_(-1) and Al□(NaR2+)-1,where R = Fe, Mg. In addition, minor substitutions include(CaMg)(NaAl)_(-1) and FeAl_(-1). The calculated d11 B value for the mineralizing fluids ranged from-12.8 to-9.7%,which is typical of S-type granites, and boron-enriched fluids predominantly derived from rhyolitic melt. Part of the tourmaline from the rhyolite porphyry crystallized during the magmatic-hydrothermal stage, whereas most tourmalines from the deposit formed in the post-magmatic hydrothermal stage. The tourmalines were deposited from a relatively reduced and acidic fluid system, and the gold predominantly precipitated during the post-magmatic hydrothermal stage in the Longtoushan deposit. | Lihua Qian Jianqing Lai Shugen Zhang Lifang Hu Rong Cao Shilong Tao | 2019 | Acta Geochimica2019，38，2： | 5 |
| 7 | The protection effect of β-CD on DNA damage induced by ultrafine TiO_2显示文摘Under the photocatalysis of 365 nm ultraviolet radiation,ultrafine TiO2 caused the oxidative damage of Teasy plasmid DNA. The damage was determined by gel-electrophoresis. Then,a different dose of β-CD was added to the reaction,and the damage was restrained. The rate of damage restraining reached 97% when the mass of β-CD was 4 times as that of TiO2. Through UV scan and IR spectroscopy,it was found that the Ti-O of ultrafine TiO2 was bound with -OH of β-CD cavum and the -OH on the surface of ultrafine TiO2 disappeared,so the formation of ?OH was controlled. The ultrafine TiO2 has been widely used,but it was determined to be carcinogenic by some research. The protection effect of β-CD to DNA in the molecular level takes a new look on the surface modification of nano particles to decrease the toxic effect. | ZHU RongRong,WANG ShiLong,SUN XiaoYu,ZHANG Rui & YAO SiDe School of Life Science and Technology,Tongji University,Shanghai 200092,China | 2007 | Science China Chemistry2007，50，2： | 5 |
| 8 | Optical single sideband polarization modulation for radio-over-fiber system and microwave photonic signal processing显示文摘An approach to implementing optical single sideband(OSSB)polarization modulation,which is a combination of two orthogonally polarized OSSB modulations with complementary phase differences between the optical carrier and the sideband,is demonstrated based on two cascaded polarization modulators(PolMs).The two PolMs are driven by two RF signals that are 90°out of phase.By properly adjusting the polarization state between the two PolMs,OSSB polarization modulation with large operation bandwidth can be realized.An experiment is performed.OSSB polarization modulation with an operation bandwidth from 2 to 35 GHz is successfully demonstrated.The spectral profile of the OSSB polarization-modulated signal is observed through an optical spectrum analyzer,and its complementary phase properties are analyzed by sending the signal to a photodetector(PD)for square-law detection.Due to the complementary phase differences between the optical carrier and the sideband along the two polarization directions,no microwave frequency component is generated after the PD.The generated OSSB polarization-modulated signal is transmitted through 25 and 50 km single-mode fiber with 50 Mbaud 16 quadrature amplitude modulation baseband data to investigate the transmission performance of the proposed system in radio-over-fiber applications,and very small error vector magnitude degradation is observed.OSSB polarization modulation is also employed to realize a microwave photonic phase shifter.A full-range tunable phase shift is obtained for 2 and 35 GHz microwave signals. | Yamei Zhang Fangzheng Zhang Shilong Pan | 2014 | Photonics Research2014，2，4： | 4 |
| 9 | MicroRNA-182 promotes pancreatic cancer cell proliferation and migration by targeting β-TrCP2显示文摘胰腺的癌症是好攻击的恶意。中部的幸存率仍然保持低,显示新奇 biomarkers 和治疗学的目标的鉴定是批评的。这里,我们在胰腺的癌症开发检验了 microRNA-182 (miR-182 ) 的角色。人的胰腺的癌症标本和房间线的分析证明 miR-182 是在胰腺的癌症的 overexpressed 并且支持肿瘤增长和侵略。-TrCP2 作为 miR-182 的一个直接目标被证实。-TrCP2 的 Silencing 增加了类似于 miR-182 overexpression 的 -catenin, 的层次。-TrCP2 的宫外的表示禁止了 -catenin 发信号的 miR-182-induced 激活。由 -TrCP2 的 miR-182 和它的颠倒的 oncogenic 效果在 vivo 被证实。这研究建议 -TrCP 和 miR-182 可以为胰腺的癌症的早察觉和治疗是可能的 biomarkers 和目标。 | Shi Wang Jiansong Ji Jingjing Song Xue Li Shilong Han Weishuai Lian Chuanwu Cao Xiaoping Zhang Maoquan Li | 2016 | Acta Biochimica et Biophysica Sinica2016，48，12： | 4 |
| 10 | A tunable and dispersion-insensitive microwave photonic filter显示文摘A tunable and dispersion-insensitive two-tap microwave photonic filter(MPF) with a complex coefficient is proposed and demonstrated.By simply adjusting a polarization controller(PC) in one tap,the filter can be tuned over the entire free spectral range(FSR) while keeping the shape of the filter unchanged.Because the two taps are both single-sideband(SSB) modulated,the filter has high tolerance to fiber dispersion.The transmission response of a system with 25-or 40-km single-mode fiber(SMF) was measured and compared with an MPF with one double sideband(DSB) modulation tap.The proposed MPF shows much better performance for long-distance fiber transmission. | ZHANG YaMei PAN ShiLong | 2013 | Chinese Science Bulletin2013，58，7： | 4 |
| 11 | Combined amendment reduces soil Cd availability and rice Cd accumulation in three consecutive rice planting seasons显示文摘The scientific application of stabilized materials has been considered an effective method for the in situ remediation of Cd-contaminated soil.This study aimed to investigate the persistence of the effect of a combined amendment of limestone and sepiolite(LS)on soil Cd availability and accumulation in rice grown in a mildly Cd-contaminated paddy field(0.45 mg/kg of Cd)over three consecutive rice seasons.1125–4500 kg/ha of LS was applied to the soil before the first rice planting season and 562.5–2250 kg/ha of LS was supplemented before the third rice planting season.The application of LS(1125–4500 kg/ha)increased the soil p H by 0.44–1.09,0.18–0.53,and 0.42–0.68 in the first,second,and third season,respectively,and decreased the soil acid-extractable Cd content by 18.2–36.4%,17.7–33.5%,and9.6–17.6%.LS application significantly decreased the Cd contents in the rice tissues.The application of 4500 kg/ha of LS decreased the Cd content in brown rice to below the National Food Limit Standard of 0.2 mg/kg(GB 2762-2017)in the three consecutive rice seasons.However,the effect of LS on the soil-rice system was significantly weakened in the third season.The supplementary application of 562.5–2250 kg/ha of LS further decreased the Cd content in brown rice by 26.1–56.5%and decreased the health risk index by 23.7–43.8%.Therefore,it was recommended to apply 4500 kg/ha of LS in the first season and to supplement2250 kg/ha of LS in the third season to effectively guarantee the clean production of rice in three consecutive rice seasons. | Wenjun Yang Shilong Wang Hang Zhou Min Zeng Jingyi Zhang Fang Huang Shiping Shan Zhaohui Guo Hongwei Yi Zhiguang Sun Jiaofeng Gu Bohan Liao | 2022 | Journal of Environmental Sciences2022，34，1： | 4 |
| 12 | An infrastructure with user-centered presentation data model for integrated management of materials data and services显示文摘With scientific research in materials science becoming more data intensive and collaborative after the announcement of the Materials Genome Initiative,the need for modern data infrastructures that facilitate the sharing of materials data and analysis tools is compelling in the materials community.In this paper,we describe the challenges of developing such infrastructure and introduce an emerging architecture with high usability.We call this architecture the Materials Genome Engineering Databases(MGED).MGED provides cloud-hosted services with features to simplify the process of collecting datasets from diverse data providers,unify data representation forms with user-centered presentation data model,and accelerate data discovery with advanced search capabilities.MGED also provides a standard service management framework to enable finding and sharing of tools for analyzing and processing data.We describe MGED’s design,current status,and how MGED supports integrated management of shared data and services. | Shilong Liu Yanjing Su Haiqing Yin Dawei Zhang Jie He Haiyou Huang Xue Jiang Xuan Wang Haiyan Gong Zhuang Li Hao Xiu Jiawang Wan Xiaotong Zhang | 2021 | npj Computational Materials2021，，1： | 4 |
| 13 | Background-free pulsed microwave signal generation based on spectral shaping and frequency-to-time mapping显示文摘A novel scheme for the generation of background-free pulsed microwave signals is proposed and experimentally demonstrated based on spectral shaping,frequency-to-time mapping,and balanced photodetection.In the proposed scheme,the optical spectral shaper,which consists of a differential group delay(DGD)element,two polarization controllers,and a polarization beam splitter,has two outputs with complementary power transfer functions.By passing a short optical pulse through the spectral shaper and a dispersive element(DE),a pulsed microwave signal is obtained after balanced photodetection.Thanks to the balanced photodetection,the lowfrequency components(i.e.,the background signal)in the electrical spectrum is suppressed,leading to the generation of a background-free pulsed microwave signal.Meanwhile,the spectral power of the obtained microwave signal is enhanced compared to that obtained by single-end detection.Experimental results for the generation of a pulsed microwave signal centered at 12.46 GHz show that the background signal can be suppressed by more than 30 dB,and the spectral power is increased by 5.5 dB.In addition,the central frequency of the obtained background-free pulsed microwave signal can be tuned by changing the DGD introduced by the DGD element,and/or by changing the dispersion of the DE. | Fangzheng Zhang Xiaozhong Ge Shilong Pan | 2014 | Photonics Research2014，2，4： | 4 |
| 14 | Protective effects of a new metalloporphyrin on paraquat-induced oxidative stress and apoptosis in N27 cells显示文摘Paraquat (PQ, 1,1'-dimethyl-4,4'-bipyridinium ) ,使用得广泛地的除草剂,为 Parkinson 的疾病的发展作为一个潜在的 etiologic 因素被建议了。在最近的年里,许多研究集中于 PQ neurotoxicity 的机制。在这研究,我们检验了锰( III )的 neuroprotective 效果 meso-tetrakis ( N , N'-diethylimidazolium )卟啉( MnTDM ),超级氧化物 dismutase/catalase 模仿,在在 1RB ( 3 )的 导致PQ 的氧化应力和 apoptosis 上一( 27 )( N27 )房间,一根 dopaminergic neuronal 房间线。结果显示 MnTDM 显著地稀释了房间生存能力,谷胱甘肽弄空,和反应的氧种类生产的导致 PQ 的损失。MnTDM 也改善了 apoptosis 的导致 PQ 的词法原子变化和 apoptosis 的增加的率。另外,我们的数据提供 MnTDM 压制了导致 PQ 的 caspase-3 劈开的直接证据,可能 PQ neurotoxicity 的一个关键事件。这些观察建议了那个氧化压力, apoptosis 在导致 PQ 的 neurotoxicity 被含有,这毒性能被 MnTDM 阻止。这些调查结果也为 Parkinson 与氧化应力联系的疾病和另外的混乱建议了一条新奇治疗学的途径。 | Ping Chen Ang Li Mengjie Zhang Meilan He Zhen Chen Xiaokang Wu Chunjun Zhao Shilong Wang Liping Liang | 2008 | Acta Biochimica et Biophysica Sinica2008，40，2： | 4 |
| 15 | Elastic Scattering of 7Be on Pb Target显示文摘 | Yang Yanyun Wang Jiansong Wang Qi Huang Meirong Ma Junbing Ma Peng Cao Xiguang Han Jianlong Bai Zhen Jin Shilong Hu Qiang Jin Lei Chen Jiangbo Zhang Xueying Chen Ruofu Hu Zhengguo Xu Shiwei Zhen Chuan Xu Zhiguo Xu Hushan Duan Liming Sun Zhiyu Chen Zhiqiang He Jianjun Li Songlin Lei Xiangguo Fu Fen Zhang Xueheng Yuan Xiaohua Du Chengming Yan Xinshuang Hu Jun Tang Shuwen Ye Ruiping Yang Kun Shi Fudong Zhang Wei Chen Ze Li Long Xu Xing Liu Longxiang Zhang Liyong Lin Qingyun Gou Boxing Xu Ge Zhou Xionghong Zhang Yuhu Xiao Guoqing | 2011 | IMP & HIRFL Annual Report2011，，1： | 4 |
| 16 | Rapid generation of ACE2 humanized inbred mouse model for COVID-19 with tetraploid complementation显示文摘Although monkeys and pigs can be infected with SARS-Co V-2,they generally have a long growth cycle and a large size that is difficult to handle in large quantities.However,the readily available rats and mice are not susceptible to SARSCo V-2 because of differences in ACE2(angiotensin-converting enzyme 2),the receptor mediating cell entry of SARSCo V-2[1].Thus,the key to establishing a mouse model of COVID-19 is to make the mice express human ACE2 protein,and therefore become SARS-Co V-2 susceptible.Recently reported COVID-19 mouse models using a random insertion transgene approach[2,3]or adenoviral approach to express h ACE2[4],lack the tissue-specificity of h ACE2 expression and might not replicate COVID-19 precisely,limiting their applications in certain studies. | Feng-Liang Liu Kaixin Wu Jiaoyang Sun Zilei Duan Xiongzhi Quan Junqi Kuang Shilong Chu Wei Pang Han Gao Ling Xu Ying-Chang Li Hai-Lin Zhang Xue-Hui ang Rong-Hua Luo Xiao-Li Feng Hans RScholer Xinwen Chen Duanqing Pei Guangming Wu Yong-Tang Zheng Jiekai Chen | 2021 | National Science Review2021，8，2： | 3 |
| 17 | Spring and autumn phenology across the Tibetan Plateau inferred from normalized difference vegetation index and solar-induced chlorophyll fluorescence显示文摘Plant phenology is a key parameter for accurately modeling ecosystem dynamics.Limited by scarce ground observations and benefiting from the rapid growth of satellite-based Earth observations,satellite data have been widely used for broad-scale phenology studies.Commonly used reflectance vegetation indices represent the emergence and senescence of photosynthetic structures(leaves),but not necessarily that of photosynthetic activities.Leveraging data of the recently emerging solar-induced chlorophyll fluorescence(SIF)that is directly related to photosynthesis,and the traditional MODIS Normalized Difference Vegetation Index(NDVI),we investigated the similarities and differences on the start and end of the growing season(SOS and EOS,respectively)of the Tibetan Plateau.We found similar spatiotemporal patterns in SIF-based SOS(SOS_(SIF))and NDVI-based SOS(SOS_(NDV)I).These spatial patterns were mainly driven by temperature in the east and by precipitation in the west.Yet the two satellite products produced different spatial patterns in EOS,likely due to their different climate dependencies.Our work demonstrates the value of big Earth data for discovering broad-scale spatiotemporal patterns,especially on regions with scarce field data.This study provides insights into extending the definition of phenology and fosters a deeper understanding of ecosystem dynamics from big data. | Fandong Meng Ling Huang Anping Chen Yao Zhang Shilong Piao | 2021 | Big Earth Data2021，5，2： | 2 |
| 18 | All-fiber-photonics-based ultralow-noise agile frequency synthesizer for X-band radars显示文摘We propose and demonstrate an agile X-band signal synthesizer with ultralow phase noise based on all-fiberphotonic techniques for radar applications. It shows phase noise of-145 dBc∕Hz(-152 dBc∕Hz) at 10 kHz(100 kHz) offset frequency for 10 GHz carrier frequency with integrated RMS timing jitter between 7.6 and 9.1 fs(integration bandwidth: 10 Hz–10 MHz) for frequencies from 9 to 11 GHz. Its frequency switching time is evaluated to be 135 ns with a 135 pHz frequency tuning resolution. In addition, the X-band linearfrequency-modulated signal generated by the proposed synthesizer shows a good pulse compression ratio approximating the theoretical value. In addition to the ultrastable X-band signals, the proposed synthesizer can also provide 0–1 GHz ultralow-jitter clocks for analog-to-digital converters(ADC) and digital-to-analog converters(DAC) in radar systems and ultralow-jitter optical pulse trains for photonic ADC in photonic radar systems.The proposed X-band synthesizer shows great performance in phase stability, switching speed, and modulation capability with robustness and potential low cost, which is enabled by an all-fiber-photonics platform and can be a compelling technology suitable for future X-band radars. | JUAN WEI DOHYEON KWON SHUANGYOU ZHANG SHILONG PAN AND JUNGWON KIM | 2018 | Photonics Research2018，9，1： | 2 |
| 19 | Dissolution-precipitation growth of uniform and clean two dimensional transition metal dichalcogenides显示文摘Two dimensional transition metal dichalcogenides(TMDCs)have attracted much interest and shown promise in many applications.However,it is challenging to obtain uniform TMDCs with clean surfaces,because of the difficulties in controlling the way the reactants are supplied to the reaction in the current chemical vapor deposition growth process.Here,we report a new growth approach called’dissolution-precipitation’(DP)growth,where the metal sources are sealed inside glass substrates to control their feeding to the reaction.Noteworthy,the diffusion of metal source inside glass to its surface provides a uniform metal source on the glass surface,and restricts the TMDC growth to only a surface reaction while eliminating unwanted gas-phase reaction.This feature gives rise to highly uniform monolayer TMDCs with a clean surface on centimeter-scale substrates.The DP growth works well for a large variety of TMDCs and their alloys,providing a solid foundation for the controlled growth of clean TMDCs by the fine control of the metal source. | Zhengyang Cai Yongjue Lai Shilong Zhao Rongjie Zhang Junyang Tan Simin Feng Jingyun Zou Lei Tang Junhao Lin Bilu Liu Hui-Ming Cheng | 2021 | National Science Review2021，8，3： | 2 |
| 20 | Effects of wildfire on soil respiration and its heterotrophic and autotrophic components in a montane coniferous forest显示文摘Aims Episodic wildfires are expected to occur more frequently under future climate change scenarios,with substantial effects on CO_(2) exchange between terrestrial ecosystems and the atmosphere.This study examined the effects of wildfire on soil respiration(R_(S))and its heterotrophic(R_(H))and autotrophic(R_(A))components,as well as their temperature responses(temperature sensitivity,Q_(10)).Methods We began this study in January 2014,8 months after a wildfire,in a montane coniferous forest in southwestern China.A trenching method was used to exclude plant roots and quantify R_(H).R_(A) was calculated by subtracting R_(H) from R_(S).Important findings From 2014 to 2015,the wildfire significantly reduced R_(S),R_(H) and R_(A) by 61.3%,42.5%and 84.0%,respectively,leading to increases in the ratio of R_(H) to R_(S),from 0.63 in the unburned stand to 0.85 in the burned stand.Ignoring diurnal differences,the wildfire did not affect the Q_(10) of R_(S) or R_(H),but substantially decreased the Q_(10) of R_(A),from 2.62 in the unburned stand to 2.08 in the burned stand.However,the daytime Q_(10) of R_(S) and R_(H) was suppressed follow-ing the wildfire by 25.1%and 28.8%,respectively,primarily due to increased daytime soil temperature.In the montane coniferous for-est,monthly precipitation but not soil temperature drove seasonal dynamics of soil CO_(2) release.Our findings help to clarify the mech-anisms underlying carbon cycling responses to natural disturbance,especially under a warmer future climate. | Jian Song Zhen Liu Yuan Zhang Tao Yan Zehao Shen Shilong Piao | 2019 | Journal of Plant Ecology2019，12，2： | 2 |
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