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Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： yun-Peng Li Hao-ran Shen Shao-Juan Wang Hao Zhang Jian hu Rui Xin Xiao-Li Sun Shou-Ke Yan Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

Multi-time Collaborative Restoration for Integrated Electrical-gas Distribution Systems Based on Rolling Optimization

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 660-671页

作者： Jingyang yun Zheng Yan yun Zhou Peichao Zhang Weidong hu Key Laboratory of Control of Power Transmission and Conversion of Ministry of Education Department of Electrical EngineeringShanghai Jiao Tong University

This paper proposes a multi-time collaborative restoration model for integrated electricity-gas distribution sys-tems(IEGDSs)considering multiple resources after extreme weather *** on the linearized power flow constraints of the unbalanced electrical distribution system(EDS)and gas distribution system(GDS),this problem can be formulated as a mixed-integer linear programming(MILP)*** improve the efficiency and veracity of the solution,a rolling optimiza-tion based two-stage method is developed with the first stage solved by a linear approximation model,and the second stage solved by real-time updated rolling *** solving the MILP problem using rolling optimization,the proposed model and solution method achieve efficient and reliable collaborative restoration of IEGDS considering multiple resources and unbal-anced operation characteristics of *** effectiveness of the proposed model and method is validated by using an IEGDS made of a 37-bus unbalanced EDS and 11-node *** Terms-Electricity-gas system,mix-integer linear programming,power system restoration.

关键词： Electricity-gas system mix-integer linear programming power system restoration

Higher palaeoelevation in the Baoshan Basin:Implications for landscape evolution at the southeastern margin of the Tibetan Plateau

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Journal of Palaeogeography 2024年第3期13卷 563-580页

作者： Yong-Jiang huang Hao-ran Zong Shi-Tao Zhang Arata Momohara Jin-Jin hu Lin-Bo Jia yun-Heng Ji Zhe-Kun Zhou Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201Yunnan ProvinceChina College of Forestry Shandong Agricultural UniversityTai'an 271018Shandong ProvinceChina Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093Yunnan ProvinceChina Graduate School of Horticulture Chiba UniversityChiba 271-8510Japan Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303Yunnan ProvinceChina

Surface uplift at the southeastern margin of the Tibetan Plateau has been widely studied,but more palaeoaltimetry data are required to better understand the elevation history of this geologically complex *** this study,fossil leaves of Abies(Pinaceae),a cool-temperate element,recovered from the latest Miocene-Pliocene Yangyi Formation of the southern Baoshan Basin,were used as a proxy to estimate the local *** on the regional modern altitude range(2100-4280 m)of the genus as well as regional temperature discrepancy(1.5℃)between the past and present,the palaeoelevation of the study area was calculated to be>2360 m above sea level as compared to 1670 m at *** result suggests that the southern Baoshan Basin experienced pronounced uplift prior to the time of fossil deposition,probably as a result of crustal shortening and thickening of the northern Baoshan Terrane during the *** infer that surface growth in areas south of the Dali Basin may have been greater than previously interpreted,and that a widespread plateau or plateau patches higher than 2000 m probably extended southwards into at least the Baoshan Basin by the latest *** also infer that the elevation of the southern Baoshan Basin has decreased by at least 690 m since then,in contrast to most other scenarios in which the elevation of the southeastern margin of the Tibetan Plateau has increased or remained close to modern levels since the late *** major cause of the inferred altitude decline is likely tectonic *** a transtensional graben basin,the Baoshan Basin has experienced pull-apart and base-fall movement since the late Miocene,which would reduce the altitude of its southern part located on the hanging *** erosion associated with the increased summer rainfall might also have played a role especially in reducing the local relief,although its contribution can be *** study provides one of the few palaeoelevation

关键词： Abies Lapse rate Palaeoaltimetry Surface uplift Tectonic movement Tibetan plateau

Organic Brønsted Acid-Catalyzed Stereoselective Cationic RAFT Polymerization:The Effect of RAFT Agents

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Chinese Journal of Polymer Science 2024年第6期42卷 711-717页

作者： Zheng-Yi Zhang Zan Yang yun Liao Sai-hu Liao Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108China State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Beijing National Laboratory for Molecular Sciences Beijing100190China

The tacticity of vinyl polymers is a key factor affecting the properties of ***,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective cationic reversible addition-fragmentation chain transfer(RAFT)polymerizations of vinyl ethers,in which the use of RAFT agents could allow the control the molecular weight and tacticity of polymer products ***,the effect of RAFT agents on the tacticity-regulation remains elusive and lacks of *** this study,we synthesized four types of RAFT agents and evaluated their influence in the stereoselective cationic polymerization of isobutyl vinyl ether in the presence of PADI as a Brønsted acid catalyst,which unveils that the Z group of RAFT agents could not only affect the polydispersity of the products,but also exert a profound effect on the *** extensive screening of the RAFT agents,high stereoregularity(isotacticity,90%m)was obtained when using dithiocarbonate ester-type RAFT agents with a benzyloxy Z group.

关键词： Bronsted acid catalysis Stereoselective cationic polymerization RAFT polymerization Chain transfer agents Tacticity

Recent advances and challenges of nitrogen/nitrate electro catalytic reduction to ammonia synthesis

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Frontiers in Energy 2024年第2期18卷 128-140页

作者： Junwen CAO Yikun hu yun ZHENG Wenqiang ZHANG Bo YU Institute of Nuclear and New Energy Technology(INET) Collaborative Innovation Center of Advanced Nuclear Energy TechnologyTsinghua UniversityBeijing 100084China Department of Chemical Engineering University of WaterlooWaterlooOntario N2L 3G1Canada Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

The Haber-Bosch process is the most widely used synthetic ammonia technology at *** its invention,it has provided an important guarantee for global food ***,the traditional Haber-Bosch ammonia synthesis process consumes a lot of energy and causes serious environmental *** the serious pressure of energy and environment,a green,clean,and sustainable ammonia synthesis route is urgently *** synthesis of ammonia is a green and mild new method for preparing ammonia,which can directly convert nitrogen or nitrate into ammonia using electricity driven by solar,wind,or water energy,without greenhouse gas and toxic gas ***,the basic mechanism of the nitrogen reduction reaction(NRR)to ammonia and nitrate reduction reaction(NO_(3)^(-))to ammonia were *** representative approaches and major technologies,such as lithium mediated electrolysis and solid oxide electrolysis cell(SOEC)electrolysis for NRR,high activity catalyst and advanced electrochemical device fabrication for(NO_(3)^(-))RR and electrochemical ammonia synthesis were *** on the above discussion and analysis,the main challenges and development directions for electrochemical ammonia synthesis were further proposed.

关键词： electrochemical ammonia synthesis nitrogen nitrate nitrogen reduction reaction(NRR)to ammonia nitrate reduction reaction(NO_(3)^(-))RR

Effect of initial ammonium concentration on a one-stage partial nitrification/anammox biofilm system:Nitrogen removal performance and the microbial community

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Journal of Environmental Sciences 2024年第9期143卷 176-188页

作者： Mengyu Zhou yun Han Yang Zhuo Fen Yu Gaoyuan hu Dangcong Peng School of Municipal and Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key Laboratory of Northwest Water Resource Environment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China

One-stage partial nitrification coupled with anammox(PN/A)technology effectively reduces the energy consumption of a biological nitrogen removal *** nitrite-oxidizing bacteria(NOB)is essential for this technology to maintain efficient nitrogen removal *** ammonium concentration(IAC)affects the degree of inhibited *** this study,the effect of the IAC on a PN/A biofilm was investigated in a moving bed biofilm *** results showed that nitrogen removal efficiency decreased from 82.49%±1.90%to 64.57%±3.96%after the IAC was reduced from 60 to 20 mg N/L,while the nitrate production ratio increased from 13.87%±0.90%to 26.50%±3.76%.NOB activity increased to1,133.86 mg N/m^(2)/day after the IAC decreased,approximately 4-fold,indicating that the IAC plays an important inhibitory role in *** rate-limiting step in the mature biofilm of the PN/A system is the nitritation process and is not shifted by the *** analysis of the microbial community structure in the biofilm indicates that the IAC was the dominant factor in changes in community *** and *** were the main anammox bacteria,and Nitrosomonas and Nitrospira were the main AOB and NOB,*** did not affect the difference in growth between *** and ***,modulating the IAC promoted the PN/A process with efficient nitrogen removal performance at medium to low ammonium concentrations.

关键词： Biological nitrogen removal Partial nitrification Anammox Ammonium concentration Biofilm

An adaptive physics-informed deep learning method for pore pressure prediction using seismic data

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Petroleum Science 2024年第2期21卷 885-902页

作者： Xin Zhang yun-hu Lu Yan Jin Mian Chen Bo Zhou State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China College of Artificial Intelligence China University of Petroleum(Beijing)Beijing102249China PetroChina Tarim Oilfield Company KorlaXinjiang841000China

Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum *** deep learning technique has been receiving more interest due to the great potential to deal with pore pressure ***,most of the traditional deep learning models are less efficient to address generalization *** fill this technical gap,in this work,we developed a new adaptive physics-informed deep learning model with high generalization capability to predict pore pressure values directly from seismic ***,the new model,named CGP-NN,consists of a novel parametric features extraction approach(1DCPP),a stacked multilayer gated recurrent model(multilayer GRU),and an adaptive physics-informed loss *** machine training,the developed model can automatically select the optimal physical model to constrain the results for each pore pressure *** CGP-NN model has the best generalization when the physicsrelated metricλ=0.5.A hybrid approach combining Eaton and Bowers methods is also proposed to build machine-learnable labels for solving the problem of few *** validate the developed model and methodology,a case study on a complex reservoir in Tarim Basin was further performed to demonstrate the high accuracy on the pore pressure prediction of new wells along with the strong generalization *** adaptive physics-informed deep learning approach presented here has potential application in the prediction of pore pressures coupled with multiple genesis mechanisms using seismic data.

关键词： Pore pressure prediction Seismic data 1D convolution pyramid pooling Adaptive physics-informed loss function High generalization capability

Visibility restoration for real-world hazy images via improved physical model and Gaussian total variation

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Frontiers of Computer Science 2024年第1期18卷 267-269页

作者： Chuan LI Enping hu Xinyu ZHANG Hao ZHOU Hailing XIONG yun LIU College of Computer and Information Science Southwest UniversityChongqing 400715China School of Big Data and Intelligent Engineering Chongqing College of International Business and EconomicsChongqing 401520China College of Artificial Intelligence Southwest UniversityChongqing 400715China College of Electronic and Information Engineering Southwest UniversityChongqing 400715China

1 Introduction Under real-world haze conditions,the existence of haze particles in the atmosphere reduces the visibility of captured ***,the noise is inevitably introduced into the degraded image,which further deteriorates the visual quality of the *** enhance the visibility and quality of outdoor real-world hazy images,numerous algorithms have been proposed to remove haze from a single input *** existing methods are broadly lumped into two categories:prior-based methods[1,2]and learning-based methods[3–6].Unfortunately,the widely used atmospheric scattering model and the corresponding haze removal methods fail to take the noise interference into account,which may result in poor visibility restoration performance.

关键词： visibility remove noise

Calcium-based polymers for suppression of soil acidification by improving acid-buffering capacity and inhibiting nitrification

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Journal of Environmental Sciences 2024年第5期139卷 138-149页

作者： Fei Kang yunshan Meng Yanning Ge yun Zhang Haixiang Gao Xueqin Ren Jie Wang Shuwen hu Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Applied Chemistry China Agricultural UniversityBeijing 100193China

Soil acidification is a major threat to agricultural sustainability in tropical and subtropical *** and environmentally friendly materials,such as calcium lignosulfonate(CaLS),calcium poly(aspartic acid)(PASP-Ca),and calcium polyγ-glutamic acid(γ-PGA-Ca),are known to effectively ameliorate soil ***,their effectiveness in inhibiting soil acidification has not been *** study aimed to evaluate the effect of CaLS,PASP-Ca,andγ-PGA-Ca on the resistance of soil toward acidification as directly and indirectly(i.e.,via nitrification)caused by the application of HNO_(3)and urea,*** comparison,Ca(OH)_(2)and lignin were used as the inorganic and organic controls,*** the materials,γ-PGA-Ca drove the substantial improvements in the pH buffering capacity(pHBC)of the soil and exhibited the greatest potential in inhibiting HNO_(3)-induced soil acidification via protonation of carboxyl,complexing with Al~(3+),and cation exchange *** acidification induced by urea,CaLS was the optimal one in inhibiting acidification and increasing exchangeable acidity during ***,the sharp reduction in the population sizes of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)confirmed the inhibition of nitrification via CaLS ***,compared to improving soil pHBC,CaLS may play a more important role in suppressing indirect ***,γ-PGA-Ca was superior to PASP-Ca and CaLS in enhancing the soil pHBC and the its resistance to acidification induced by HNO_(3) addition,whereas CaLS was the best at suppressing urea-driven soil acidification by inhibiting *** conclusion,these results provide a reference for inhibiting soil re-acidification in intensive agricultural systems.

关键词： Calcium-based polymer Soil acidification pH buffering capacity Nitrification inhibition