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    题名 作者 年代 出处 被引量
1Impact of Grid Connection of Large-Scale Wind Farms on Power System Small-Signal Angular Stability显示文摘The grid connection of a large-scale wind farm could change the load flow/configuration of a power system and introduce dynamic interactions with the synchronous generators(SGs),thus affecting system small-signal angular stability.This paper proposes an approach for the separate examination of the impact of those affecting factors,i.e.,the change of load flow/configuration and dynamic interactions brought about by the grid connection of the wind farm,on power system smallsignal angular stability.Both cases of grid connection of the wind farm,either displacing synchronous generators or being directly added into the power system,are considered.By using the proposed approach,how much the effect of the change of load flow/configuration brought about by the wind farm can be examined,while the degree of impact of the dynamic interaction of the wind farm with the SGs can be investigated separately.Thus,a clearer picture and better understanding of the power system small-signal angular stability as affected by grid connection of the large-scale wind farm can be achieved.An example of the power system with grid connection of a wind farm is presented to demonstrate the proposed approach.Wenjuan Du Jingtian Bi Tong Wang Haifeng Wang 2015CSEE Journal of Power and Energy Systems2015,1,2:39
2Kinsenoside attenuates osteoarthritis by repolarizing macrophages through inactivating NF-κB/MAPK signaling and protecting chondrocytes显示文摘The objective was to investigate the effect of kinsenoside(Kin) treatments on macrophage polarity and evaluate the resulting protection of chondrocytes to attenuate osteoarthritis(OA) progression.RAW264.7 macrophages were polarized to M1/M2 subtypes then administered with different concentrations of Kin. The polarization transitions were evaluated with quantitative real-time polymerase chain reaction(q RT-PCR), confocal observation and flow cytometry analysis. The mechanism of Kin repolarizing M1 macrophages was evaluated by Western blot. Further, macrophage conditioned medium(CM) and IL-1β were administered to chondrocytes. Micro-CT scanning and histological observations were conducted in vivo on anterior cruciate ligament transection(ACLT) mice with or without Kin treatment. We found that Kin repolarized M1 macrophages to the M2 phenotype. Mechanistically, Kin inhibited the phosphorylation of IκBα, which further reduced the downstream phosphorylation of P65 in nuclear factor-κB(NF-κB) signaling. Moreover, Kin inhibited mitogen-activated protein kinases(MAPK) signaling molecules p-JNK, p-ERK and p-P38. Additionally, Kin attenuated macrophage CM and IL-1β-induced chondrocyte damage. In vivo, Kin reduced the infiltration of M1 macrophages,promoted M2 macrophages in the synovium, inhibited subchondral bone destruction and reduced articular cartilage damage induced by ACLT. All the results indicated that Kin is an effective therapeutic candidate for OA treatment.Feng Zhou Jingtian Mei Xiuguo Han Hanjun Li Shengbing Yang Minqi Wang Linyang Chu Han Qiao Tingting Tang 2019Acta Pharmaceutica Sinica B2019,9,5:35
3Intravenous chemotherapy for resected gastric cancer:meta-analysis of randomized controlled trials显示文摘AIM: To assess the safety and efficacy of different intravenous chemotherapeutic regimens in patiedts with gastric acrcinomas who had undergone gastrectomy.Jian-KunHu Zhi-xinChen Zong-GuangZhou BoZhang JingTian Jia-Pin 2002World Journal of Gastroenterology2002,8,6:31
4An Analysis and Modeling Study of a Sea Fog Event over the Yellow and Bohai Seas显示文摘In this study, a sea fog event which occurred on 27 March 2005 over the Yellow and Bohai Seas was investigated obser- vationally and numerically. Almost all available observational data were used, including satellite imagery of Geostationary Opera- tional Environmental Satellite (GOES)-9, three data sets from station observations at Dandong, Dalian and Qingdao, objectively reanalyzed data of final run analysis (FNL) issued by the National Center for Environmental Prediction (NCEP) and Regional At- mospheric Modeling System (RAMS) results. Synoptic conditions and fog characteristics were analyzed. The fog formed when warm, moist air was advected northwards over the cool water of the Yellow and Bohai Seas, and dissipated when a cold front brought northerly winds and cool, dry air. In order to better understand the fog formation mechanism, a high-resolution RAMS modeling with a 6 km×6 km grid, initialized and validated by FNL data, was designed. A 48 h modeling that started from 12 UTC 26 March 2005 reproduced the main characteristics of this sea fog event. The simulated lower visibility area agreed reasonably well with the sea fog region identified from the satellite imagery. Advection cooling effect seemed to play a significant role in the fog formation.FU Gang GUO Jingtian Angeline Pendergrass LI Pengyuan 2008Journal of Ocean University of China2008,7,1:26
5Photoreduction of CO_2 to methanol over Bi_2S_3/CdS photocatalyst under visible light irradiation显示文摘The Bi2S3,CdS and Bi2S3/CdS photocatalysts were prepared by direct reactions between their corresponding salt and thiourea in a hy- drothermal autoclave.The photocatalytic activities of these photocatalysts for reducing CO2 to CH3OH under visible light irradiation have been investigated.The results show that the photocatalytic activity and visible light response of Bi2S3 are higher than those of CdS.The Bi2S3 modification can enhance the photocatalytic activity and visible light response of CdS.The photocatalytic activity of Bi2S3/CdS hetero-junction photocatalyst was the highest and the highest yields of methanol was 613μmol/g when the weight proportion of Bi2S3 to CdS was 15%,which was about three times as large as that of CdS or two times of that of Bi2S3.Xin Li Juntao Chen Huiling Li Jingtian Li Yitao Xu Yingju Liu Jiarong Zhou 2011Journal of Natural Gas Chemistry2011,20,4:11
6Signaling pathways in cancer-associated fibroblasts and targeted therapy for cancer显示文摘To flourish,cancers greatly depend on their surrounding tumor microenvironment(TME),and cancer-associated fibroblasts(CAFs)in TME are critical for cancer occurrence and progression because of their versatile roles in extracellular matrix remodeling,maintenance of sternness,blood vessel formation,modulation of tumor metabolism,immune response,and promotion of cancer cell proliferation,migration,invasion,and therapeutic resistance.CAFs are highly heterogeneous stromal cells and their crosstalk with cancer cells is mediated by a complex and intricate signaling network consisting of transforming growth factor-beta,phosphoinositide 3-kinase/AKT/mammalian target of rapamycin,mitogen-activated protein kinase,Wnt,Janus kinase/signal transducers and activators of transcription,epidermal growth factor receptor,Hippo,and nuclear factor kappa-light-chain-enhancer of activated B cells,etc.,signaling pathways.These signals in CAFs exhibit their own special characteristics during the cancer progression and have the potential to be targeted for anticancer therapy.Therefore,a comprehensive understanding of these signaling cascades in interactions between cancer cells and CAFs is necessary to fully realize the pivotal roles of CAFs in cancers.Herein,in this review,we will summarize the enormous amounts of findings on the signals mediating crosstalk of CAFs with cancer cells and its related targets or trials.Further,we hypothesize three potential targeting strategies,including,namely,epithelial-mesenchymal common targets,sequential target perturbation,and crosstalk-directed signaling targets,paving the way for CAF-directed or host cell-directed antitumor therapy.Fanglong Wu Jin Yang Junjiang Liu Ye Wang Jingtian Mu Qingxiang Zeng Shuzhi Deng Hongmei Zhou 2021Signal Transduction and Targeted Therapy2021,6,7:9
7Mobility and sulfidization of heavy metals in sediments of a shallow eutrophic lake, Lake Taihu, China显示文摘The technique of DGT(diffusive gradients in thin films) using three diffusive gel thicknesses was applied to estimate the mobility and bioavailability of heavy metals in sediments and porewater of Lake Taihu, China. The DGT results showed significantly positive correlations between Co, Pb, Cd and Mn, and Ni and Fe concentrations in porewater. Cu and Zn showed a significantly negative correlation with Mn, due to Cu combination with carbonates and Zn derived from agricultural pollution, respectively. The rank order of average concentrations of Co, Ni and Cd at each station was DGT1.92>DGT0.78> DGT0.39, suggesting stronger resupply from sediments to porewater when using thicker diffusive gels. Comparing centrifugation and DGT measurements, Co, Ni and Cd are highly labile; Mn and Fe are moderately labile; and Cu, Zn and Pb are slightly labile. The variations of AVS concentrations in sediment cores indicate that metal sulfides in deeper layers are easily diffused into surface sediments.Shouliang Huo Jingtian Zhang Kevin M.Yeager Beidou Xi Yanwen Qin Zhuoshi He Fengchang Wu 2015Journal of Environmental Sciences2015,27,5:8
8A 60-year sedimentary record of natural and anthropogenic impacts on Lake Chenghai,China显示文摘Recent sediments from Lake Chenghai,China,were investigated at high temporal resolution to trace both natural and anthropogenic effects on the lake using total organic carbon(TOC),total nitrogen(TN),total phosphorus(TP),organic phosphorus(P o),inorganic phosphorus(P i) and organic carbon and nitrogen stable isotopes(δ 13 C org and δ 15 N) in a 137 Cs-dated sediment core.The results indicated that the sedimentary record covers the last 60 years,during which the lake had undergone apparent changes in nutrient sources and productivity in response to nutrient loading.Prior to the late 1980s,the nutrient contents in sediments mainly originated from algae and lake productivity was relatively stable.Since the late 1980s,increasing TOC,TN and TP concentrations together with the change of δ 13 C org and δ 15 N suggested anthropogenic perturbations in nutrient loading and lake productivity.Endogenic nutrients derived from algae and anthropogenic inputs were two important sources of sedimentary nutrients.The anthropogenic nutrients mainly originated from the discharge of industrial wastewater and artificial cultivation of Spirulina after the middle 1980s,and domestic wastewater discharged from Yongsheng County since 1993.Fengyu Zan Shouliang Huo Beidou Xi Jingtian Zhang Haiqing Liao Yue Wang Kevin M.Yeager 2012Journal of Environmental Sciences2012,24,4:8
9Analyses of nitrobenzene, benzene and aniline in environmental water samples by headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry显示文摘A headspace solid phase microextrac- tion coupled with gas chromatography mass spec- trometry (HS-SPME/GC-MS) method was estab- lished for analyzing nitrobenzene, benzene and ani- line in environmental water samples simultaneously. Factors affecting extraction efficiency (SPME fiber selection, acidity, temperature, salt addition, extrac- tion time, headspace, etc) were verified. Under opti- mal extraction conditions, the detection limits are 0.50, 0.11 and 1.00 μg/L for nitrobenzene, benzene and aniline, respectively. The results indicate that this method is capable of making sensitive and accuracy analyses on nitrobenzene, benzene and aniline in environmental water samples.CHEN Ming YIN Yongguang TAI Chao ZHANG Qinghua LIU Jiyan HU Jingtian JIANG Guibin 2006Chinese Science Bulletin2006,51,13:8
10Arsenic fractionation and contamination assessment in sediments of thirteen lakes from the East Plain and Yungui Plateau Ecoregions, China显示文摘Arsenic(As) fractions in the sediments of seven lakes from East Plain Ecoregion and six lakes from Yungui Plateau Ecoregion, China, were investigated. Results indicated that the total As concentrations in sediment samples of lakes of the East Plain Lake Ecoregion are higher than those of Yungui Plateau Lake Ecoregion. Residual As is the main fraction in sediment samples of lakes from both ecoregions, followed by reducible As and soluble or oxidizable As. The total As is correlated to oxidizable As and residual As in sediment samples from both lake ecoregions. As distribution in sediment samples of lakes of the East Plain Ecoregion appears to be affected by human activity, while the As origin mainly comes from natural sources in sediment samples of lakes in the Yungui Plateau Ecoregion. The potential ecological risk index and geoaccumulation index values suggest 'low to moderate' risk degree and 'unpolluted to moderately polluted' for As in the studied lake sediments.Fengyu Zan Shouliang Huo Jingtian Zhang Li Zhang Beidou Xi Lieyu Zhang 2014Journal of Environmental Sciences2014,26,10:7
11Mechanism and kinetics study on the ozonolysis reaction of 2,3,7,8-TCDD in the atmosphere显示文摘The ozonolysis of 2,3,7,8-tetra-chlorodibenzo-p-dioxin(2,3,7,8-TCDD) is an efcient degradation way in the atmosphere. The ozonolysis process and possible reactions path of Criegee Intermediates with NO and H2 O are introduced in detail at the method of MPWB1K/6-31+G(d,p)//MPWB1K/6-311+G(3df,2p) level. In ozonolysis, H2O is an important source of OH radical formation and initiated the subsequent degradation reaction. The Rice-Ramsperger-Kassel-Marcus(RRKM) theory was applied to calculate rate constants with the temperature ranging from 200 to 600 K. The rate constant of reaction between 2,3,7,8-TCDD and O3 is 4.80 × 10 20cm3/(mole·sec) at 298 K and 760 Torr. The atmospheric lifetime of the reaction species was estimated according to rate constants, which is helpful for the atmospheric model study on the degradation and risk assessment of dioxin.Jing Bai Xiaomin Sun Chenxi Zhang Chen Gong Jingtian Hu Jianghua Zhang 2014Journal of Environmental Sciences2014,26,1:6
12A Historical Sedimentary Record of Mercury in a Shallow Eutrophic Lake: Impacts of Human Activities and Climate Change显示文摘Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding changes in pollution levels and thus trace anthropogenic or natural influences. This research investigates the 100-year history of mercury (Hg) deposition in sediments from Chao Lake, a shallow eutrophic lake in China. The results indicate that the Hg deposition history can be separated into three stages (pre-1960s, 1960s–1980s, and post-1980s) over the last 100 years. Before the 1960s, Hg concentrations in the sediment cores varied little and had no spatial difference. Since the 1960s, the concentration of Hg began to increase gradually, and showed a higher concentration of contamination in the western half of the lake region than in the eastern half of the lake region due to all kinds of centralized human-input sources. The influences of anthropogenic factors and hydrological change are revealed by analyzing correlations between Hg and heavy metals (Fe, Co, Cr, Cu, Mn, Pb, and Zn), stable carbon and nitrogen isotopes (d13C and d15N), nutrients, particle sizes, and meteorological factors. The results show that Hg pollution intensified after the 1960s, mainly due to hydrological change, rapid regional development and urbanization, and the proliferation of anthropogenic Hg sources. Furthermore, the temperature, wind speed, and evaporation are found to interactively influence the environmental behaviors and environmental fate of Hg.Hanxiao Zhang Shouliang Huo Kevin M. Yeager Beidou Xi Jingtian Zhang Fengchang Wu 2019Engineering2019,5,2:6
13Small-signal Angular Stability of Power System as Affected by Grid-connected Variable Speed Wind Generators—A Survey of Recent Representative Works显示文摘This paper reviews the status and progress of the investigation on power system small-signal angular stability as affected by grid-connected variable speed wind generators(VSWGs).The review is carried out on the basis of a survey of recently published representative papers.Strategies of the investigation made in those selected papers are classified into two groups:1)VSWGs displacing synchronous generators(SGs);2)VSWGs simply being added in a power system.The diversification of the results of the investigation is highlighted in the survey.Careful analysis on two strategies of the investigation is conducted in this paper.It is revealed that in the strategy of VSWGs displacing SGs,there are two factors which could affect power system small-signal angular stability differently:1)Withdrawing the SGs’dynamics;2)adding the VSWGs’dynamics.In the strategy of adding VSWGs in the power system,there are also two affecting factors:1)Change of load flow brought about by the VSWGs;2)dynamic interactions with the SGs introduced by the VSWGs.Hence diversified results of the investigation obtained so far are not only due to the dependence of the investigation on sample power systems used,but also caused by the mixture of different affecting factors.This paper is concluded with a summary of key issues of the investigation for future work.Wenjuan Du Jingtian Bi H.F.Wang 2017CSEE Journal of Power and Energy Systems2017,3,3:6
14Source apportionment of perfluoroalkyl substances in surface sediments from lakes in Jiangsu Province,China:Comparison of three receptor models显示文摘Receptor models have been proved as useful tools to identify source categories and quantitatively calculate the contributions of extracted sources.In this study,sixty surface sediment samples were collected from fourteen lakes in Jiangsu Province,China.The total concentrations of C_4–C_(14)-perfluoroalkyl carboxylic acids and perfluorooctane sulfonic acid(∑_(12)PFASs) in sediments ranged from 0.264 to 4.44 ng/g dw(dry weight),with an average of 1.76 ng/g dw.Three commonly-applied receptor models,namely principal component analysis-multiple linear regression(PCA-MLR),positive matrix factorization(PMF) and Unmix models,were employed to apportion PFAS sources in sediments.Overall,these three models all could well track the ∑_(12) PFASs concentrations as well as the concentrations explained in sediments.These three models identified consistently four PFAS sources:the textile treatment sources,the fluoropolymer processing aid/fluororesin coating sources,the textile treatment/metal plating sources and the precious metal sources,contributing 28.1%,37.0%,29.7% and 5.3% by PCA-MLR model,30.60%,39.3%,22.4% and 7.7% by PMF model,and 20.6%,52.4%,20.2% and 6.8% by Unmix model to the ∑_(12) PFASs,respectively.Comparative statistics of multiple analytical methods could minimize individual-method weaknesses and provide convergent results to enhance the persuasiveness of the conclusions.The findings could give us a better knowledge of PFAS sources in aquatic environments.Yanjie Qi Zhuoshi He Shouliang Huo Jingtian Zhang Beidou Xi Shibin Hu 2017Journal of Environmental Sciences2017,29,7:6
15Rapid decolorization of water soluble azo-dyes by nanosized zero-valent iron immobilized on the exchange resin显示文摘Nanosized zero-valent iron (NZVI) supported on the cation exchange resin was synthesized and applied to decompose some water soluble azo dyes. The decomposition efficiency for azo dyes was evaluated by using the aqueous suspensions and parked column of this material. Batch experiments indicated that this novel material exhibited excellent degradation ability for 0.05 g·L1 of Acid Orange 7, Acid Orange 8, Acid Orange 10, Sunset Yellow, and Methyl Orange, with decolorization ratio up to 95% in 4 min; pH value was the key factor for degradation and H+ was one of the reactants; adsorption of azo dyes onto the material existed at the beginning but reduced gradually until disappearing completely. For the packed column system, 58%~90% of azo dyes were decomposed in the 1st circle of solution passing through the column, and the adsorption onto the materials could accelerate the degradation azo dyes with the increasing reaction time. During the degradation process, Fe2+, the product of NZVI, was exchanged to the resin again and could be reduced to Fe0 by KBH4 for reusing. The 10th refreshed NZVI possessed reductive activity up to 90% of the newly systhesized NZVI. Decomposing pollutants in the aqueous solution with columns packed with NZVI immobilized on the cation exchange resin is a promising technology that can solve the reclaiming and refreshing problem of NZVI.ZHAO ZongShan LIU JingFu TAI Chao ZHOU QunFang HU JingTian JIANG GuiBin 2008Science China Chemistry2008,51,2:6
16Characterization, treatment and releases of PBDEs and PAHs in a typical municipal sewage treatment plant situated beside an urban river, East China显示文摘Characterization, treatment and releases of eight polybrominated diphenyl ethers (PBDEs) congeners and sixteen polycyclic aromatic hydrocarbons (PAHs) in wastewater were evaluated along the treatment processes of a typical secondary treatment municipal sewage treatment plant (STP) (in Hefei City) situated the beside Nanfei River, East China. The findings showed that the average concentrations of the total PBDEs in raw wastewater and treated effluent were 188.578 and 36.884 ng/L respectively. Brominated diphenyl ether (BDE) 209 congener, the predominant PBDE in the STP and Nanfei River, could be related to the discharge of car-industry-derived wastes. For PAHs, the average concentrations in raw wastewater and treated effluent were 5758.8 and 2240.4 ng/L respectively, with naphthalene, benzo[a]pyrene and indeno[1,2,3-c,d]pyrene being detected at the highest concentrations. PAHs mainly originate from the combustion of biomass/coal and petroleum. The STP reduced about 80% of the PBDEs and 61% of the PAHs, which were eliminated mainly by sedimentation processes. The removal rates of PBDEs/PAHs increased with the increase of their solid-water partitioning coefficients. Accordingly, the STP's effluent, containing some PBDE congeners (e.g., BDE 47, 99 and 209, etc.) and low-molecular-weight PAHs, could be an important contributor of these contaminants' input to Nanfei River. It resulted in a significant increase of PBDE/PAH concentrations and PAH toxicological risk in the river water downstream. About 4.040 kg/yr of PBDEs and 245.324 kg/yr of PAHs could be released into the Nanfei River. The current conventional wastewater treatment processes should be improved to remove the relatively low-molecular-weight PBDEs/PAHs more effectively.Xiaowei Wang Beidou Xi Shouliang Huo Wenjun Sun Hongwei Pan Jingtian Zhang Yuqing Ren Hongliang Liu 2013Journal of Environmental Sciences2013,25,7:6
17Microbial bioavailability of dissolved organic nitrogen(DON) in the sediments of Lake Shankou,Northeastern China显示文摘Dissolved organic nitrogen(DON)extracted from Lake Shankou sediments using KCl was isolated into hydrophobic and hydrophilic fractions.The bioavailabilities of the hydrophobic and hydrophilic fractions to three types of bacterial communities collected from sediments,activated sludge and compost products were examined.The DON recoveries obtained by DAX-8 and cation exchange resins treatment were 96.17% ± 1.58% and 98.14% ±0% for the samples obtained from N4 and N14 stations,respectively.After 25 days of incubation at 25°C,most DON(59% to 96%)was degraded.Hydrophilic DON exhibited a higher reduction rate than hydrophobic DON during the growth phase.Untreated wastewater from Changshuihe town was the main degradable DON source to station N4,and 93% of hydrophilic DON and 80% of hydrophobic DON were degraded.Station N14 received a large amount of refractory DON from forest soils and exhibited DON degradation rates of 82% and 71% for the hydrophilic and hydrophobic fractions,respectively.Amino acid contents and fluorescence intensities were also analyzed.Approximately 27% to 74% of amino acids were taken up by day 5,and their concentration gradually increased in the following days due to the decomposition of dissolved proteins.Parallel factor analysis resulted in identification of tryptophan-like proteins,tyrosine-like proteins and FA-like substances.During the growth phase,40%–51% of the tryptophan-like proteins were taken up by bacteria,and the accumulation of tyrosine-like proteins was attributed to the release of biotic substances.The concentration of the FA-like substances decreased due to microbial decomposition.Mingzhou Su Jingtian Zhang Shouliang Huo Beidou Xi Fei Hua Fengyu Zan Guangren Qian Jianyong Liu 2016Journal of Environmental Sciences2016,28,4:5
18The Structure and Formation Mechanism of a Sea Fog Event over the Yellow Sea显示文摘In this paper, a heavy sea fog event occurring over the Yellow Sea on 11 April 2004 was investigated based upon observational and modeling analyses. From the observational analyses, this sea fog event is a typical advection cooling case. Sea surface temperature(SST) and specific humidity(SH) show strong gradients from south to north, in which warm water is located in the south and consequently, moisture is larger in the south than in the north due to evaporation processes. After fog formation, evaporation process provides more moisture into the air and further contributes to fog evolution. The sea fog event was reproduced by the Regional Atmospheric Modeling System(RAMS) reasonably. The roles of important physical processes such as radiation, turbulence as well as atmospheric stratification in sea fog's structure and its formation mechanisms were analyzed using the model results. The roles of long wave radiation cooling, turbulence as well as atmospheric stratification were analyzed based on the modeling results. It is found that the long wave radiative cooling at the fog top plays an important role in cooling down the fog layer through turbulence mixing. The fog top cooling can overpower warming from the surface. Sea fog develops upward with the aid of turbulence. The buoyancy term, i.e., the unstable layer, contributes to the generation of TKE in the fog region. However, the temperature inversion layer prevents fog from growing upward.GUO Jingtian LI Pengyuan FU Gang ZHANG Wei GAO Shanhong ZHANG Suping 2015Journal of Ocean University of China2015,14,1:4
19To image,or not to image:class-specific diffractive cameras with all-optical erasure of undesired objects显示文摘Privacy protection is a growing concern in the digital era,with machine vision techniques widely used throughout public and private settings.Existing methods address this growing problem by,e.g.,encrypting camera images or obscuring/blurring the imaged information through digital algorithms.Here,we demonstrate a camera design that performs class-specific imaging of target objects with instantaneous all-optical erasure of other classes of objects.This diffractive camera consists of transmissive surfaces structured using deep learning to perform selective imaging of target classes of objects positioned at its input field-of-view.After their fabrication,the thin diffractive layers collectively perform optical mode filtering to accurately form images of the objects that belong to a target data class or group of classes,while instantaneously erasing objects of the other data classes at the output field-of-view.Using the same framework,we also demonstrate the design of class-specific permutation and class-specific linear transformation cameras,where the objects of a target data class are pixel-wise permuted or linearly transformed following an arbitrarily selected transformation matrix for all-optical class-specific encryption,while the other classes of objects are irreversibly erased from the output image.The success of class-specific diffractive cameras was experimentally demonstrated using terahertz(THz)waves and 3D-printed diffractive layers that selectively imaged only one class of the MNIST handwritten digit dataset,all-optically erasing the other handwritten digits.This diffractive camera design can be scaled to different parts of the electromagnetic spectrum,including,e.g.,the visible and infrared wavelengths,to provide transformative opportunities for privacy-preserving digital cameras and task-specific data-efficient imaging.Bijie Bai Yi Luo Tianyi Gan Jingtian Hu Yuhang Li Yifan Zhao Deniz Mengu Mona Jarrahi Aydogan Ozcan 2022eLight2022,2,1:4
20Apparent relationships between anthropogenic factors and climate change indicators and POPs deposition in a lacustrine system显示文摘Climate change and anthropogenic activities are expected to impact the environmental behaviors and fates of persistent organic pollutants(POPs), however, quantitative studies on these combined factors are scarce. In this study, dichlorodiphenyltrichloroethane(DDTs), polycyclic aromatic hydrocarbons(PAHs), and polychlorinated biphenyls(PCBs)were used as examples to identify how and when those factors may be related to the deposition of POPs in the sediment of Lake Chaohu, China, using generalized additive models(GAMs). Three historical trends of DDT, PAH, and PCB deposition were delineated in a dated sediment core encompassing ~100 years of historical record: a steady state or gradually increasing stage, a rapidly increasing stage, and a declining stage. The GAM results showed that aquatic total phosphorus(TP) concentrations and regional GDP(anthropogenic factors) were dominant contributors to POP accumulation rates in the lake sediment. The fitted relationships between air temperature and sedimentary DDT and PAH concentrations were linear and negative, while a positive linear relationship was found for PCBs, suggesting that Lake Chaohu may have become a net source for DDTs and PAHs, and a sink for PCBs, under a progressively warming climate.Hanxiao Zhang Shouliang Huo Kevin M. Yeager Chaocan Li Beidou Xi Jingtian Zhang Zhuoshi He Chunzi Ma 2019Journal of Environmental Sciences2019,31,9:4
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