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Aerosol-radiation interaction and its variation in North china within 2015–2019 period under continuous PM_(2.5)improvements

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Journal of Environmental Sciences 2024年第2期136卷 81-94页

作者： Zhe Lv Xiaoqi wang Wei Wei Huahua Bai Xiaoyu Liu Guohao Li Shuiyuan cheng Department of Environmental Science and Engineering Beijing University of TechnologyBeijing 100124China Key Laboratory of Beijing on Regional Air Pollution Control Beijing 100124China Beijing Municipal Research Institute of Eco-Environmental Protection Beijing 100037China Beijing Key Laboratory of Urban Atmospheric Volatile Organic Compounds Pollution Control and Application Beijing 100037China

A study was conducted on aerosol-radiation interactions over six cities in this region within the 2015–2019 ***-Chem simulations on 2017 showed that based on the six-city average,the aerosol load(PM_(2.5)concentrations)of 121.9,49.6,43.3,and 66.3μg/m^(3)in January,April,July,and October,mainly lowered the level of downward shortwave radiation by 38.9,24.0,59.1,and 24.4 W/m~2and reduced the boundary layer height by 79.9,40.8,87.4,and 31.0 m,via scattering and absorbing solar *** sensitivity of meteorological changes to identical aerosol loads varied in the order July>January>October and ***,the cooling and stabilizing effects of aerosols further led to increases in PM_(2.5),by23.0,3.4,4.6,and 7.3μg/m^(3)respectively in the four *** sensitivity of the effect of aerosols on PM_(2.5)was greatest in January rather than in July,contrary to the effect on ***,a negative linear relation was observed between daily BLH reductions and aerosol loads in fall and winter,and between PM_(2.5)increases and aerosol loads in all *** the PM_(2.5)pollution improvements in this region,the aerosol radiative forcing was effectively *** should result in daily BLH increases of 10–24 m in fall and winter,and the estimates in Beijing agreed well with the corresponding results based on AMDAR ***,the reduction in aerosol radiation effects brought about daily PM_(2.5)decreases of 1.6-2.8μg/m^(3),accounting for 7.0%–17.7%in PM_(2.5)improvements.

关键词： Radiative forcing Aerosol PM_(2.5) Boundary layer height(BLH) North china

A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

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Research in Astronomy and Astrophysics 2024年第6期24卷 191-200页

作者： Xiao-Gu Zhong Jian-cheng wang Yong-Yun Chen Xiao-Ling Yu College of Physics and Electronic Engineering Qujing Normal UniversityQujing 655011China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

A possible quasi-periodic oscillation(QPO) at frequency 7.045 × 10^(-5) Hz is found in the narrow-line Seyfert 1galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April *** find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram,the Weighted Wavelet Z-transform and the *** analyze the data in 0.3–0.6 keV,0.6–1 keV,1–3 keV and 3–10 keV energy bands,and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV *** then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^(-5) Hz,and use a model to fit *** find that the QPO signal mainly comes from the X-ray hot corona.

关键词： X-rays:galaxies galaxies:Seyfert accretion accretion disks radiation mechanisms:general

Syntheses of amphiphilic biodegradable copolymers of poly(ethyl ethylene phosphate) and poly(3-hydroxybutyrate) for drug delivery

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Science china Chemistry 2009年第7期52卷 961-968页

作者： cheng Jing1 & wang Jun2 1 Department of Polymer Science and Engineering, university of Science and Technology of china, Hefei 230026, china 2 Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, university of Science and Technology of china, Hefei 230027, china Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China Hefei National Laboratory for Physical Sciences at Microscale School of Life Sciences University of Science and Technology of China Hefei 230027 China

Biodegradable and amphiphilic triblock copolymers poly(ethyl ethylene phosphate)-poly(3-hydroxybutyrate)-poly(ethyl ethylene phosphate) (PEEP-b-PHB-b-PEEP) have been successfully synthesized through ring-opening polymerization. The structures are confirmed by gel permeation chromatography and NMR analyses. Crystallization investigated by X-ray diffraction reveals that the block copolymer with higher content of poly(ethyl ethylene phosphate) (PEEP) is more amorphous, showing decreased crystallizability. The obtained copolymers self-assemble into biodegradable nanoparticles with a coreshell micellar structure in aqueous solution, verified by the probe-based fluorescence measurements and transmission electronic microscopy (TEM) observation. The hydrophobic poly(3-hydroxybutyrate) (PHB) block serves as the core of the micelles and the micelles are stabilized by the hydrophilic PEEP block. The size and size distribution are related to the compositions of the copolymers. Paclitaxel (PTX) has been encapsulated into the micelles as a model drug and a sustained drug release from the micelles is observed. MTT assay also demonstrates that the block copolymers are biocompatible, rendering these copolymers attractive for drug delivery.

关键词： poly(3-hydroxybutyrate) polyphosphoester drug delivery polymeric nanoparticles

Highly crystalline Y3Al5O12:Ce3+ phosphor-in-silica glass ceramics for high-power solid-state lighting

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Journal of Rare Earths 2024年第11期42卷 2051-2057页

作者： Shisheng Lin Hang Lin Hongyi Yang Pengfei wang Ping Sui Ju Xu Yao cheng Yuansheng wang Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of china Xiamen Institute of Rare-earth Materials Haixi InstitutesChinese Academy of Sciences College of Chemistry and Materials Science Fujian Normal University

The pursuit of high-brightness solid-state lighting（SSL） stimulates the development of all-inorganic color converters with high *** is required that the fluorescent material is able to cope with the extreme condition generated from the irradiation of high-power-density excitation *** such,in this work,we developed a new composite color converter,i,e.,Y3Al5O12:Ce3+phosphor-in-silica glass ceramic(YAG:Ce3+PiSGC).Remarkably,the amorphous SiO2matrix spontaneously transforms into tetragonal SiO2crystallites during co-sintering with crystallization fraction reaching up to>90%（almost full ceramization）.The activation energy for crystallization Ecand Avrami index n of amorphous silica oxide are 298.5 kJ/mol and 1.71,indicating the diffusion-controlled glass crystallization *** fabricated prototype high-power phosphor-converted white light-emitting diode（pc-wLED） and phosphor-converted white laser diode（pc-wLD） based on YAG:Ce3+PiSGC show satisfactory photometric/colorimetric *** developed color co nverters have combined merits of environmental protection property,cost-effective manufacturing,good luminescent performance,and easy *** study highlights a new kind of opto-functional composite material and its application as an efficient color converter in high-power solid-state lightings.

关键词： Glass ceramics Laser-driven white light Rare earths White light-emitting diode Y3Al5O12:Ce3+

The Properties of Solution Precursor Plasma Spray Nanostructured Thermal Barrier Coatings

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Journal of Wuhan university of Technology(Materials Science) 2010年第6期25卷 924-928页

作者：闵捷 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

About 300 μm thickness uniform thermal barrier coatings （TBCs） were deposited on the 1Cr18Ni9Ti samples by solution precursor plasma spray （SPPS）.The analysis methods,such as TEM,SEM,and XRD were used to characterize the coatings in the aspects of microstructure and phase *** samples were quenched from 1121 ℃ to room temperature by forced-air to measure the thermal cycling *** density were measured by means of water *** experimental results show that grain size of the SPPS TBCs is about 30 nm with desired tetragonal phase ZrO2,and the SPPS TBCs（with 16% porosity） consist of arcuate pores,gelatin and melted *** hardness of the coatings is HR45Y38.5 and bond strength between coatings and substrates is 24.2 *** thermal shock test show the coatings have a average life of 500 cycles which is about 2.5 times than that of conventional air plasma spray （APS） TBCs.

关键词： SPPS TBCs nanostructure properties

Mechanism and performance of a lithium chloride accelerator

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Petroleum Science 2011年第3期8卷 328-334页

作者： wang chengwen wang Ruihe cheng Rongchao Chen Erding School of Petroleum Engineering China University of Petroleum Qingdao Shandong 266555 China Department of Drilling Strategy and Planning CNPC Drilling Research Institute Beijing 100195 China Drilling Engineering and Technology Corp. Shengli Petroleum Administration Bureau Dongying Shandong 257064 China

To address present concerns about thickening time and high early-strength in deepwater cementing at low temperatures when using conventional accelerators, a new type of set-accelerating admixture comprising of lithium chloride, aluminium hydroxide and alkaline metal chlorides, named as LS-A, was studied in this paper. Mechanism analysis and performance tests show that the accelerator LS-A accelerated the hydration of tri- and dicalcium silicates （C3S and C2S） at low-temperatures by speeding up the breakdown of the protective hydration film and shortening the hydration induction period. Therefore, LS-A could shorten the low-temperature thickening time and the transition time of critical gel strength from 48 to 240 Pa of the Class-G cement slurry, and improve the early compressive strength of set cement at low-temperatures. It exhibited better performance than calcium chloride and had no effect on the type of hydration products, which remain the same as those of neat Class-G cement, i.e. the calcium silicate gel, Ca（OH）2 crystals and a small amount of ettringite AFt crystals. LS-A provides an effective way to guarantee the safety of cementing operations, and to solve the problems of low temperature and shallow water/gas flowing faced in deepwater cementing.

关键词： Deepwater cementing accelerator lithium chloride Class-G cement mechanism

The *** climate abrupt events in the early and middle Holocene:Stalagmite oxygen isotope record from Maolan,Guizhou,china

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Science china Earth Sciences 2005年第4期48卷 530-537页

作者： QIN Jiaming1, YUAN Daoxian1, cheng Hai2, LIN Yushi1, ZHANG Meiliang1, wang Fuxing1, R. L. Edwards2, wang Hua1 & RAN Jingcheng3 1. The Karst Dynamic Laboratory, IKG, CAGS, Guilin 541004, china 2. Geology and Geophysics Department, Minnesota university, MN55455, USA 3. The Management of Maolan National Nature Reserve, Libo 558400, china 1. The Karst Dynamic Laboratory 541004 IKG CAGS Guilin China 2. Geology and Geophysics Department Minnesota University 55455 MN USA 3. The Management of Maolan National Nature Reserve 558400 Libo China

The isotope records which range from 3.9 kaBP to 15.7 kaBP with an average resolution of 90 a have been obtained from 45 cm to 193.6 cm of the upper part of D4 stalagmite from Dongguo Cave in Libo, Guizhou, by using system TIMS U-series dating and carbon and oxygen stable isotope *** study indicates that the last cold event, the YD (Younger Dryas) event, of the last glacial period was apparently shown in D4 record, which started from 12.80 kaBP and ended in 11.58 kaBP, with a great range of drop in temperature. The end of the last glacial period was consistent with the termination I in oceanic isotope records and was with time limit of 11.3 kaBP. The three most distinct cold events in the early and middle Holocene occurred respectively in 10.91 kaBP, 8.27 kaBP and 4.75 kaBP, with a range of drop in tem- perature reaching 2—5℃. The climate abrupt events in thousand and hundred years scale re- corded in stalagmite δ O can be compared to those in GISP2 ice cores from Greenland in their 18 happening time and the range of their lasting time. The cold events in 8.27 kaBP and 4.75 kaBP can also be compared to CC3 stalagmite records in Ireland, which indicate that climate changes of short range in china monsoon areas, western Europe and polar regions, have the same driv- ing factor. This has a global significance. In addition, the trend of record curves in some time- stages is apparently different, which reflects probably the difference between environment in monsoon climate areas and in polar regions.

关键词： isotope record, climate event, stalagmite, Libo, Guizhou.

Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern china

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Science china Earth Sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,wang Hongmei2,YI Yi1,HU Chaoyong1, CAI Yanjun3 & cheng Hai4 1. Faculty of Earth Science,china university of Geosciences,Wuhan 430074,china 2. School of Environmental Studies,china university of Geosciences,Wuhan 430074,china 3. SKLLQG,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,china 4. Department of Geology and Geophysics,university of Minnesota,MN55455,USA 1. Faculty of Earth Science China University of Geosciences 430074 Wuhan China 2. School of Environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. Department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern china’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14 to C26 in carbon number, maximizing at C16, with a second dominance at C22. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C20). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2-ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

Prestoring lithium into SnO_(2)coated 3D carbon fiber cloth framework as dendrite-free lithium metal anode

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Particuology 2024年第1期84卷 89-97页

作者： Tao Wei Yanyan Zhou cheng Sun Lesheng Liu Sijia wang Mengting wang Ye Liu Qing Huang Quanchao Zhuang Yongfu Tang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang212003China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing210037China Li-ion Batteries Lab School of Materials Science and EngineeringChina University of Mining and TechnologyXuzhouChina Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao066004China

For several decades,the promise of implementing of lithium(Li)metal anodes has been regarded as the"holy grail"for Li-based ***,we have proposed a facile design of a carbon fiber cloth(CFC)framework coated with SnO_(2)nanoparticles through a hydrothermal process,which served as a reliable host for prestoring molten Li to produce a CFC@SnO_(2)@Li composite ***,TEM,HRTEM,XPS and different electrochemical characterizations were carried *** to the synergetic effects of the 3D conductive CFC and the coated lithiophilic SnO_(2)nanoparticles,the designed CFC@SnO_(2)@Li electrodes can buffer the volume changes and reduce the local current density,thus suppress the Li dendrites during ***,the CFC@SnO_(2)electrodes showed a high and stable CE of 98.6%for 1000 cycles at a current density of 1 mA cm^(-2)(1 mAh cm^(-2)).What is more,at a high current density of 5 mA cm^(-2)and a high areal capacity of 5 mAh cm^(-2),the symmetric cell displayed relatively low overpotential and long cycling lifetime of 1600 *** results confirm its great potential as lithium metal anodes in practical battery applications.

关键词： Lithiophilic Lithium metal anodes SnO_(2) 3D anode Dendrite-free