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Enzymatic preparation of hydrophobic biomass with one-pot synthesis and the oil removal performance

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Journal of Environmental Sciences 2023年第2期124卷 105-116页

作者： Dan Peng Wenjie li Xujun liang liuchun zheng Xuetao guo Department of Transportation and Environment Shenzhen Institute of Information TechnologyShenzhen 518172China School of Earth and Environment Anhui University of Science&TechnologyHuainan 232001China School of Resources and Environmental Science Quanzhou Normal UniversityQuanzhou 362000China Department of Civil and Environmental Engineering University of MichiganAnn ArborMI 481092125USA School of Environment South China Normal UniversityGuangzhou Higher Education Mega CenterGuangzhou 510006China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China

Oil pollution is causing deleterious damage to aquatic ecosystems and human health.The utilization of agricultural waste such as corn stalk(CS)to produce biosorbents has been considered an ecofriendly and efficient approach for removing oil.However,most previous studies focused on the modification of the whole CS,which is inefficient due to the heterogeneity of CS.In this study,corn stalk pith(CP),which has excellent amphipathic characteristics,was selected to prepare a high-efficiency oil sorbent by grafting dodecyl gallate(DG,a long-chain alkyl)onto CP surface lignin via laccase mediation.The modified biomass(DGCP)shows high hydrophobicity(water contact angle=140.2°)and superoleophilicity(oil contact angle=0°)and exhibits a high oil sorption capacity(46.43 g/g).In addition,DGCP has good stability and reusability for adsorbing oil from the aqueous phase.Kinetic and isotherm models and two-dimensional correlation spectroscopy integrated with FTIR analyses revealed that the main sorption mechanism involves the H-bond effect,hydrophobic effect and van der Waals force.This work provides an ecofriendly method to prepare oil sorbents and new insights into the mechanisms underlying the removal of spilled oil from wastewater.

关键词： Biomass Enzymatic modification Hydrophobicity Oil sorption Two-dimensional correlation spectroscopy

Analysis of genetic diversity and prediction of Larix species distribution in the Qinghai–Tibet Plateau,China

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Journal of Forestry Research 2023年第3期34卷 705-715页

作者： Qiqiang guo Huie li Weilie zheng Jinwen Pan Jie Lu Jiangrong li Yu zheng Institute for Forest Resources&Environment of Guizhou Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou ProvinceGuizhou UniversityGuiyang 550025People’s Republic of China College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China College of Agriculture Guizhou UniversityGuiyang 550025People’s Republic of China Institute of Tibet Plateau Ecology Tibet Agriculture and Animal Husbandry UniversityNyingchi Tibet 860000People’s Republic of China Key Laboratory of Forest Ecology in Tibet Plateau(Tibet Agriculture and Animal Husbandry University) Ministry of EducationNyingchi Tibet 860000People’s Republic of China Plant Research Center Chengdu Botanical GardenChengdu 610083People’s Republic of China

Larix resources in the Qinghai-Tibet Plateau have important ecological and economic values.However,the lack of genetic diversity background and related research hinders the development of conservation strategies.In this study,genetic diversity and distribution of fi ve Larix species were investigated.Using 19 polymorphic microsatellite markers to study 272 representative individuals from 13 populations,the results show low genetic diversity at the population level,with variation explained mainly by diff erentiation among populations.The Larix populations were classifi ed into two clades,one formed by eight populations,including three of the species in this study,L.kongboensis,L.speciosa,and L.potaninii var.australis.The other clade consists of fi ve populations,including the other two species in this study,L.griffi thii and L.himalaica.Genetic distance of the species was aff ected by geographical isolation and genetic diversity was mainly aff ected by altitude.The area suitable for Larix spp.decreased during the Last Glacial Maximum compared to the current distribution according to the niche model,but should increase in future climate scenarios(2050s),expanding westward along the Himalayas.These results provide an important scientifi c basis for the development of conservation strategies and further the sustainable utilization of Larix resources in the Qinghai-Tibet Plateau.

关键词： Larix spp. Genetic diversity Phylogenetic relationship Genetic structure Ecological niche modeling Qinghai-Tibet Plateau

Wind speed retrieval using GNSS-R technique with geographic partitioning

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Satellite Navigation 2023年第1期4卷 140-154,I0005页

作者： zheng li Fei guo Fade Chen Zhiyu Zhang Xiaohong Zhang School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

In this paper,the efect of geographical location on Cyclone Global Navigation Satellite System(CYGNSS)observables is demonstrated for the frst time.It is found that the observables corresponding to the same wind speed vary with geographic location regularly.Although latitude and longitude information is included in the conventional method,it cannot efectively reduce the errors caused by geographic diferences due to the non-monotonic changes of observables with respect to latitude and longitude.Thus,an improved method for Global Navigation Satellite System Refectometry(GNSS-R)wind speed retrieval that takes geographical diferences into account is proposed.The sea surface is divided into diferent areas for independent wind speed retrieval,and the training set is resampled by considering high wind speed.To balance between the retrieval accuracies of high and low wind speeds,the results with the random training samples and the resampling samples are fused.Compared with the conventional method,in the range of 0–20 m/s,the improved method reduces the Root Mean Square Error(RMSE)of retrieved wind speeds from 1.52 to 1.34 m/s,and enhances the correlation coefcient from 0.86 to 0.90;while in the range of 20–30 m/s,the RMSE decreases from 8.07 to 4.06 m/s,and the correlation coefcient increases from 0.04 to 0.45.Interestingly,the SNR observations are moderately correlated with marine gravities,showing correlation coefcients of 0.5–0.6,which may provide a useful reference for marine gravity retrieval using GNSS-R in the future.

关键词： CYGNSS Geographical diferences Ocean wind speed GNSS refectometry Marine gravity

Insertion sequence transposition activates antimycobacteriophage immunity through an Isr2-silenced lipid metabolism gene island

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mlife 2024年第1期3卷 87-100页

作者： Yakun li Yuyun Wei Xiao guo Xiaohui li lining Lu lihua Hu zheng-guo He State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangxi Research Center for Microbial and Enzyme Engineering TechnologyCollege of Life Scienceand TechnologyGuangxi UniversityNanningChina

Insertion sequences(ISs)exist widely in bacterial genomes,but their roles in the evolution of bacterial antiphage defense remain to be clarified.Here,we report that,under the pressure of phage infection,the IS1o96 transposition of Mycobacterium smegmatis into the Isr2 gene can occur at high frequencies,which endows the mutant mycobacterium with a broad-spectrum antiphage ability.Lsr2 functions as a negative regulator and directly silences expression of a gene island composed of 11 lipid metabolism-related genes.The complete or partial loss of the gene island leads to a significant decrease of bacteriophage adsorption to the mycobacterium,thus defending against phage infection.Strikingly,a phage that has evolved mutations in two tail-filament genes can re-escape from the Isr2 inactivation-triggered host defense.This study uncovered a new signaling pathway for activating antimycobacteriophage immunity by Is transposition and provided insight into the natural evolution of bacterial antiphage defense.

关键词： antiphage defense bacteriophage gene island insertion sequence mycobacteria

Cubic multi-ions-doped Na_(2)TiO_(3) nanorod-like coatings:Structure-stable,highly efficient platform for ions-exchanged release to immunomodulatory promotion on vascularized bone apposition

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Bioactive Materials 2022年第12期7卷 72-90页

作者： Dongmei Yu Bo li Meng Yu Shuo guo zheng guo Yong Han a State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049ShaanxiChina Department of Orthopaedics Tangdu HospitalFourth Military Medical UniversityXi’an710038ShaanxiChina

The dissolution-derived release of bioactive ions from ceramic coatings on metallic implants,despite improving osseointegration,renders a concern on the interfacial breakdown of the metal/coating/bone system during longterm service.Consequently,persistent efforts to seek alternative strategies instead of dissolution-derived activation are pressingly carrying out.Inspired by bone mineral containing ions as Ca2+,Mg2+,Sr2+and Zn2+,here we hydrothermally grew the quadruple ions co-doped Na2TiO3 nanorod-like coatings.The co-doped ions partially substitute Na+in Na2TiO3,and can be efficiently released from cubic lattice via exchange with Na+in fluid rather than dissolution,endowing the coatings superior long-term stability of structure and bond strength.Regulated by the coatings-conditioned extracellular ions,TLR4-NFκB signalling is enhanced to act primarily in macrophages(MΦs)at 6 h while CaSR-PI3K-Akt1 signalling is potentiated to act predominately since 24 h,triggering MΦs in a M1 response early and then in a M2 response to sequentially secrete diverse cytokines.Acting on endothelial and mesenchymal stem cells with the released ions and cytokines,the immunomodulatory coatings greatly promote Type-H(CD31hiEmcnhi)angiogenesis and osteogenesis in vitro and in vivo,providing new insights into orchestrating insoluble ceramics-coated implants for early vascularized osseointegration in combination with long-term fixation to bone.

关键词： Nanorod-like coating Ion doping Sodium titanate Immunomodulation Angiogenesis Osseointegration

Effects of process parameters on the growth behavior and granule size distribution of iron ore mixtures in a novel high-shear granulator

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International Journal of Minerals,Metallurgy and Materials 2022年第12期29卷 2152-2161页

作者： Yang You Jiabao guo Gang li Zhuang zheng Yong li Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

This work proposes a novel horizontal high-shear granulator for iron ore granulation before sintering process.The granulation behavior such as growth process and structure of granules were firstly analyzed,followed by the effects of operation conditions such as water content,initial particle size distribution,and the concentrate ratio.The results show that the granule size increased significantly with increasing the granulation time,and the structure of granule can be divided into three types:non-nuclei,single-nuclei,and multi-nuclei.Water promotes the coalescence and growth of particles,and a better granulation performance was obtained at the water content of 8.8wt%under the current raw material conditions.Increasing the nuclei particle ratio led to an increase in average size of granules and permeability of the granules bed,but a decrease in growth index.Besides,with increasing of concentrate ratio,granulation performance such as granule size,bed permeability,and uniformity became worse.

关键词： horizontal high-shear granulation iron ore granule structure granulation performance size distribution

BP-LMS-based BDS-3 power system positioning method

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Global Energy Interconnection 2022年第6期5卷 666-674页

作者： Ruifeng Zhao Jiangang Lu Wenxin guo Wenjie zheng Shiming li Guangdong Power Grid Co. Ltd.Power Dispatching and Control CenterGuangzhou 510000P.R.China

The BeiDou-3 navigation satellite system(BDS-3)provides a full-domain high-precision positioning service for the power system to ensure safe and stable operation.However,BDS-3 power system positioning faces certain challenges,such as complex electromagnetic interference and incomplete error elimination.Herein,a back propagation neural network-improved least mean square(BP-LMS)adaptive filtering method is proposed for the BDS-3 full-domain and high-precision power system positioning,which utilizes the loss function to update the weight of the BP hidden layer,computes the pseudo compensation range,and eliminates the impact of electromagnetic interference to enhance the accuracy of power system positioning.Simulation results confirm the superior performance of BP-LMS in positioning accuracy and error elimination.Compared with LMS and normalized least mean square(NLMS),the filtering error of the proposed BP-LMS adaptive filtering method is decreased by 57.14%and 51.38%,respectively.

关键词： BDS-3 BP-LMS Error elimination Full-domain and high-precision positioning Power system

Assessment of Building Physical Vulnerability in Earthquake‑Debris Flow Disaster Chain

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International Journal of Disaster Risk Science 2023年第4期14卷 666-679页

作者： Hao zheng Zhifei Deng Lanlan guo Jifu liu lianyou liu Tiewei li Huan zheng Tao zheng Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Academy of Disaster Reduction and Emergency Management Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Department of Fire Commanding China Fire and Rescue InstituteBeijing 102202China China Railway First Group Construction and Installation Engineering Co. Ltd.Xi’an 710054China

Large earthquakes not only directly damage buildings but also trigger debris fows,which cause secondary damage to buildings,forming a more destructive earthquake-debris fow disaster chain.A quantitative assessment of building vulnerability is essential for damage assessment after a disaster and for pre-disaster prevention.Using mechanical analysis based on pushover,a physical vulnerability assessment model of buildings in the earthquake-debris fow disaster chain is proposed to assess the vulnerability of buildings in Beichuan County,China.Based on the specifc sequence of events in the earthquake-debris fow disaster chain,the seismic vulnerability of buildings is 79%,the fow impact and burial vulnerabilities of damaged buildings to debris fow are 92%and 28%respectively,and the holistic vulnerability of buildings under the disaster chain is 57%.By comparing diferent vulnerability assessment methods,we observed that the physical vulnerability of buildings under the disaster chain process is not equal to the statistical summation of the vulnerabilities to independent hazards,which implies that the structural properties and vulnerability of buildings have changed during the disaster chain process.Our results provide an integrated explanation of building vulnerability,which is essential for understanding building vulnerability in earthquake-debris fow disaster chain and building vulnerability under other disaster chains.

关键词： Building physical vulnerability Debris fow Disaster chain Earthquake

Free involutive Hom-semigroups and Hom-associative algebras

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Frontiers of Mathematics in China 2016年第2期11卷 497-508页

作者： Shanghua zheng li guo Department of Mathematics Jiangxi Normal University Nanchang 330022 China Department of Mathematics and Computer Science Rutgers University NewarkNJ 07102 USA

当它的 unary 操作是趋于增加的并且是复杂物时，我们构造免费 Hom-semigroups。我们建设的方法由括的词。作为后果，我们获得一个集合为 unary 操作在一样的条件下面产生的免费 Hom 联合的代数学。

关键词：自由半群结合代数对合一元运算元操作施工方乘法