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Journal of Innovative Optical Health Sciences 2014年第6期7卷 1-8页

作者： Yande Liu Yanrui Zhou yuanyuan pan Institute of Optics-Mechanics-Electronics Technology and Application(OMETA) School of Mechanical and Electronical Engineering East China Jiaotong University Nanchang 330013P.R.China

Variable selection is applied widely for visible-near infrared(Vis-NIR)spectroscopy analysis of internal quality in *** spectral variable selection methods were compared for online quantitative analysis of soluble solids content(SSC)in navel *** window partial least squares(MW-PLS),Monte Carlo uninformative variables elimination(MC-UVE)and wavelet transform(WT)combined with the MC-UVE method were used to select the spectral variables and develop the calibration models of online analysis of SSC in navel *** performances of these methods were compared for modeling the Vis NIR data sets of navel orange *** show that the WT-MC-UVE methods gave better calibration models with the higher correlation cofficient(r)of 0.89 and lower root mean square error of prediction(RMSEP)of 0.54 at 5 fruits per *** concluded that Vis NIR spectroscopy coupled with WT-MC-UVE may be a fast and efective tool for online quantitative analysis of SSC in navel oranges.

关键词： Vis NIR spectroscopy variables selection soluble solids content wavelet transform moving window paurtial least squares Monte Carlo uninformative variables elimination

Multiproxy Paleosol Evidence for Jurassic Paleoclimate Fluctuations in the Sichuan Basin,SW China

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2105-2124页

作者： LI Jun WEN Xingyue pan yuanyuan HUANG Chengmin Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065China College of Urban Environment Lanzhou City UniversityLanzhou 730070China School of Environmental Science and Engineering China West Normal UniversityNanchongSichuan 637002China

Paleoclimate reconstruction of continental environments has been hampered by the limited evidence.A thick sequence of Jurassic continental deposits in the Sichuan Basin,Southwest China yields abundant paleosols that may offer valuable insights regarding Jurassic climate scenarios.A succession of 169 paleosols belonging to Protosols,Calcisols,and Argillisols from 23 detailed stratigraphic sections was recognized and characterized macro-and micromorphologically and assessed for mineral and geochemical *** paleoclimate reconstructions using bulk geochemical proxies,the depth to and the stable oxygen isotopic composition of paleosol carbonates indicated a predominant alternation of semiarid and arid cool/warm-temperate climatic conditions punctuated by several episodes of subhumid and humid climates that generally prevailed in the Sichuan Basin during the *** estimated paleoatmospheric CO_(2)concentrations(pCO_(2))from calcic paleosols yielded a low range of~104±58 to~610±152 ppmv during the Middle *** terrestrial paleotemperature changes in the Sichuan Basin coincided with the pCO_(2)variations,which probably resulted from global geological events(e.g.,volcanic activities,magmatic and oceanic events,and the ephemeral caps development)in the Middle *** climatic fluctuations in the basin were likely attributed to true polar wander due to global plate motion,megamonsoon effect linked to global and regional paleogeography,and regional paleotopography.

关键词： Jurassic climatic continental

Evaluation of perfluorinated compounds in seven wastewater treatment plants in Beijing urban areas

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Science China Chemistry 2011年第3期54卷 552-558页

作者： pan yuanyuan SHI YaLi WANG JieMing CAI YaQi State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The presence of perfluorinated compounds(PFCs)in seven major wastewater treatment plants(WWTPs)in Beijing was investigated in the current *** detected nine PFCs in all the wastewater and sludge *** acid(PFOA)is the dominant PFCs in influents and effluents,while perfluorooctane sulfonate(PFOS)is the major contaminant in *** highest PFC concentration was found in plants at Qinghe and Jiuxianqiao WWTP,while the lowest was found at Fangzhuang *** total values of PFC range from 2.88 to 176 ng/L in influents,from 5.48 to 498 ng/L in effluents,and from 1.21 to 32.0 ng/g(dry wt)in *** fact that effluents usually contain higher levels of PFCs than influents suggests that additional PFCs are produced during the wastewater treatment ***,PFOS decreases in effluents than in influents in 62%of the water *** may be due to the adsorption and removal of the sludge during the active *** carboxylates(PFCAs)were found significantly correlated with each other in the effluents,which may indicate their similar sources or the existence of their potential precursors in the wastewater or treatment *** mass flows of PFC discharges into WWTPs are 0.4–51.4 mg/day,and the mass flows of PFCs in effluents exceed those in influents by 127%.Domestic and commercial wastewaters are suggested to be the major sources of PFC pollution in WWTPs in Beijing.

关键词： perfluorinated compounds wastewater sludge mass flow

A GATA-type transcription factor AcAREB for nitrogen metabolism is involved in regulation of cephalosporin biosynthesis in Acremonium chrysogenum

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Science China(Life Sciences) 2017年第9期60卷 958-967页

作者： Feifei Guan yuanyuan pan Jinyang Li Gang Liu State Key Laboratory of Mycology Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

In filamentous fungi,nitrogen metabolism is repressed by GATA-type zinc finger transcription *** metabolite repression has been found to affect antibiotic production,but the mechanism is still poorly ***,encoding a homologue of fungal GATA-type regulatory protein,was cloned from Acremonium *** disruption and genetic complementation demonstrated that AcareB plays a key role in utilization of ammonium,glutamine and *** addition,significant reduction of cephalosporin production in the AcareB disruption mutant indicated that AcareB is important for cephalosporin *** consistence with it,the transcriptional level of cephalosporin biosynthetic genes was significantly decreased in the AcareB disruption *** mobility shift assay showed that AcAREB directly bound to the intergenic regions of pcbAB-pcbC,cefD1-cefD2 and *** analysis showed that all the AcAREB binding sites contained the consensus GATA *** is negatively autoregulated during cephalosporin ***,another GATA zinc-finger protein encoded by AcareA positively regulates the transcription of ***,AcareB does not regulate the transcription of *** results indicated that AcAREB plays an important role in both regulation of nitrogen metabolism and cephalosporin production in ***.

关键词： AcareB Acremonium chrysogenum cephalosporin biosynthesis GATA-type transcription factor regulation

Remarkable enhancement of bleomycin production through precise amplification of its biosynthetic gene cluster in Streptomyces verticillus

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Science China(Life Sciences) 2022年第6期65卷 1248-1256页

作者： Hong Li Wenyan Gao Yifan Cui yuanyuan pan Gang Liu State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China The Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100864China

Amplification of biosynthetic gene clusters is important to increase secondary metabolite ***,the copy number of amplified gene clusters is difficult to control *** this study,the tandem amplification of a 70 kb bleomycin biosynthetic gene cluster was precisely regulated through the combined strategy of a Zou A-dependent DNA amplification system and double-reporter-guided recombinant selection in Streptomyces verticillus *** production of bleomycin in the recombinant strain containing six copies of the bleomycin gene cluster was 9.59-fold higher than that in the wild-type *** combined strategy used in this study is powerful and applicable for precisely regulating the amplification of gene clusters and improving the corresponding secondary metabolite production.

关键词： bleomycin precise regulation amplification of gene cluster strain improvement

Perfluorooctane sulfonate (PFOS) and other fluorochemicals in viscera and muscle of farmed pigs and chickens in Beijing,China

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Chinese Science Bulletin 2010年第31期55卷 3550-3555页

作者： WANG JieMing SHI YaLi pan yuanyuan CAI YaQi State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy ofSciences Beijing 100085 China

Eleven perfluorinated compounds(PFCs) were determined in tissue samples from farmed pigs and chickens(n=143) that were purchased in Beijing in March *** total PFCs mean concentration was the highest in pig liver(3.438 ng g-1 wet weight(ww)),followed by pig kidney(0.508 ng g-1(ww)),pig heart(0.167 ng g-1(ww)),chicken liver(0.098 ng g-1(ww)),chicken heart(0.050 ng g-1(ww)),pork loin(0.018 ng g-1(ww)),and chicken breast(0.012 ng g-1(ww)).Among the PFCs analyzed,perfluorooctane sulfonate(PFOS) was the predominant compound in viscera and muscle of farmed pigs and *** addition,a strong linear correlation(r = 0.932) was observed between the concentrations of PFOS and perfluoroundecanoic acid(PFUnDA) in pig *** preliminary conclusion is that there is little potential risk of exposure to PFCs via the consumption of these products in Beijing.

关键词：含氟化合物 PFOS 全氟辛烷猪内脏鸡肝北京养殖磺酸

Perfluorinated compounds in milk, milk powder and yoghurt purchased from markets in China

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Chinese Science Bulletin 2010年第11期55卷 1020-1025页

The exposure to perfluorinated compounds (PFCs) through the diet for humans is of great concern. Among the diet, dairy products are in great demand. This paper reports the study on the levels of 9 perfluorinated acids and 2 fluorotelomer acids in milk, milk powder and yoghurt purchased from Chinese markets from 2008 to 2009. The analytes were quantitated by high performance liquid chromatography/electrospray tandem mass spectrometry (HPLC-ESI-MS/MS). In milk samples, perfluoroheptanoic acid (PFHpA) and perfluorononanoic acid (PFNA) were detected frequently, both in 68% of samples. In milk powder samples, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and PFNA were the only detected PFCs and none of them was observed in more than 35% of samples. In yoghurt, PFOA was the most frequently detected compound, found in 69% of samples. None of fluorotelomer acids was observed in any samples. The mean concentrations of total PFCs were 178 pg/g (wet weight) in milk, 98 pg/g (dry weight) in milk powder and 42 pg/g in yoghurt (wet weight). It is notable that the data of this study indicate significant differences (P<0.001) among three kinds of packaging of milk in the concentration of total PFCs. A preliminary human health risk assessment of milk and dairy products consumption was conducted in this study. For adults, the mean daily intake of PFOS and total PFCs was equal to or lower than 23 and 167 pg kg-1 d-1 (body weight), respectively.

关键词：全氟化合物牛奶样品中国市场酸奶奶粉电喷雾串联质谱全氟辛酸铵高效液相色谱

Enhanced zinc storage performance of mixed valent manganese oxide for flexible coaxial fiber zinc-ion battery by limited reduction control

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Journal of Materials Science & Technology 2021年第15期74卷 52-59页

作者： Xiaobei Zang Li Lingtong Jiaxin Meng Lijia Liu yuanyuan pan Qingguo Shao Ning Cao School of Materials Science and Engineering.China University of Petroleum(East China) Qingdao266580China Department of Chemistry University of Western Ontario1151 Richmond StreetLondonOntarioN6A5B7Canada State Key Laboratory of Heavy Oil Processing Institute of New EnergyCollege of Chemical EngineeringChina University of Petroleum(East China)Qingdao266580China

While manganese-based cathodes have been intensively studied for zinc-ion batteries(ZIBs),the limited rate capability and cycle life have always been a difficult problem to be ***,we report a mixed valent manganese oxide(MnOx)cathode with superior electrochemical performance,which exhibits a high specific capacity of 450 mA h/g at 0.2 C and a satisfactory specific capacity of 158.3 mA h/g at a high rate of 5 *** mixed cathode system reduces the charge transfer resistance,and show good surface stability and adsorption properties,so it is beneficial for the storage of Zn^(2+).Meanwhile,coaxial fiber ZIBs(CFZIBs)with splendid flexibility are assembled utilizing the elaborately prepared cathode *** CFZIBs achieve a reversible capacity of 255.8 m A h/g and the capacity retention rate is as high as 80%after 1000 bending *** study provides new opportunities for designing ZIBs with high performance and high flexibility.

关键词： Mixed valent manganese oxide Limited reduction Storage mechanism Flexible zinc-ion battery Coaxial fiber structure

Radical-Enabled Bicyclization Cascades of Oxygen-Tethered 1,7-Enynes Leading to Skeletally Diverse Polycyclic Chromen-2-ones

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Chinese Journal of Chemistry 2017年第3期35卷 323-334页

作者： Bo Jiang Jie Li yuanyuan pan Wenjuan Hao Guigen Li Shujiang Tu School of Chemistry and Chemical Engineering Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials Jiangsu Normal University Xuzhou Jiangsu 221116 China Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 United States Institute of Chemistry & BioMedical Sciences Collaborative Innovation Center of Chemistry for Life Sciences Nanjing University Nanjing Jiangsu 210093 China

Catalytic bicyclization cascades of oxygen-tethered 1,7-enynes with simple cycloalkanes or aryl sulfonhydrazides have been established via subsequent multiple C-C bond-forming events from alkynyl/alkenyl functions, delivering a series of densely functionalized tetracyclic chromen-2-ones in a functional-group-compatible manner. In the former, Fe-catalyzed spiro-bicyclization involves radical addition, 6-exo-dig cyclization, H-abstraction and 5-endo-trig cyclization sequences under mild conditions, resulting in new spiro-fused cyclopenta[c]chromen-2-ones via dual α,α-C(sp3)-H abstractions. The latter enables in-situ sulfonylation and desulfonylation of oxygen-tethered 1,7-enynes to realize the construction of multiple C-C bonds, thereby leading to the formation of naphtho[2,3-c]chromen-6-ones.

关键词： bicyclization radical reaction 1 7-enynes fused chromen-2-ones C(sp3)-H functionalization

High-performance sub-10-nm monolayer black phosphorene tunneling transistors

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Nano Research 2018年第5期11卷 2658-2668页

作者： Hong Li Jun Tie Jingzhen Li Meng Ye Han Zhang Xiuying Zhang yuanyuan pan Yangyang Wang Ruge Quhe Feng pan Jing Lu College of Mechanical and Material Engineering North China University of Technology Beijing 100144 China State Key Laboratory of Mesoscopic Physics and Department of Physics Peking University Beijing 100871 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China School of Advanced Materials Peking University Shenzhen Graduate School Shenzhen 518055 China Nanophotonics and Optoelectronics Research Center Qian Xuesen Laboratory of Space Technology China Academy of Space Technology Beijing 100094 China State Key Laboratory of Information Photonics and Optical Communications & School of Science Beijing University of Posts and Telecommunications Beijing 100876 China

Moore＇s law is approaching its physical limit. Tunneling field-effect transistors （TFETs） based on two-dimensional （2D） materials provide a possible scheme to extend Moore＇s law down to the sub-10-nm region owing to the electrostatic integrity and absence of dangling bonds in 2D materials. We report an ab initio quantum transport study on the device performance of monolayer （ML） black phosphorene （BP） TFETs in the sub-10-nm scale （6-10 nm）. Under the optimal schemes, the ML BP TFETs show excellent device performance along the armchair transport direction. The on-state current, delay time, and power dissipation of the optimal sub-10-nm ML BP TFETs significantly surpass the latest International Technology Roadmap for Semiconductors （ITRS） requirements for high- performance devices. The subthreshold swings are 56-100 mV/dec, which are much lower than those of their Schottky barrier and metal oxide semiconductor field-effect transistor counterparts.

关键词： black phosphorene tunneling field-effect transistor device performance ab initio quantum transport simulation