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Associations of Time Spent on Study and Sleep with Anxiety and Depressive Symptoms in Junior High School Students:Report from the Large-Scale Monitoring of Basic education Data in China

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International Journal of Mental Health promotion 2023年第9期25卷 1053-1065页

作者： Hao Yao Shuzhen Chen institute of higher education Tongji UniversityShanghai200092China Faculty of education East China Normal UniversityShanghai200062China

In the context of the COVID-19 pandemic and under the pressure of high competitiveness for higher education in China,junior high school students’mental health is facing greater *** the time allocation of study and sleep is necessary for developing effective prevention and treatment *** on a survey of 31,057 junior high school students in 47 junior high schools in Gansu Province,China's Mainland,the study analyzed the associations of time spent on study and sleep with anxiety and depressive symptoms among junior high school students through chi-square test,ANOVA,logistic regression model and threshold regression *** was found that 18.4%–21.1%of junior high school students had mild and above anxiety and depressive *** junior high school students were more likely to have anxiety and depressive *** addition,time spent on study was significantly and positively associated with anxiety and depressive symptoms and time spent on sleep was significantly and negatively associated with anxiety and depressive *** sleepers were more likely to suffer from anxiety and depressive *** after-school study time appropriately and getting more sleep are beneficial in reducing anxiety and depression,but it is more important to ensure time of *** the reduction of anxiety and depressive symptoms,the maximum time spent on study after school should not exceed 1.92 h,the minimum time spent on sleep at night should be more than 7 h and a 40-min lunch break should be guaranteed at noon.

关键词： Time spent on study time spent on sleep anxiety and depressive symptoms threshold regression

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Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCS Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry I.Nazarov Jorge Labella Alexey V.Kuzmin Maxim A.Faraonov Evgenii N.Ivanov Salavat S.Khasanov Tomas Torres Mikhail K.Islyaikin Dmitri V.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid institute of Solid-State Physics RAS 142432 Chernogolovka Research institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo institute for Advanced Research in Chemical Sciences Universidad Autonoma de Madrid28049 Madrid IMDEA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

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High-performance ZIF-8 membranes:preparation and their uranium adsorption performance

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辐射研究与辐射工艺学报 2024年第5期42卷 24-37页

作者： CUI Shuaichuan DENG Ziqi HUANG Yifan LIU Shihan WANG Xingxing CHEN Shusen LI Ziming ZHANG Yifan DENG Pengyang School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Chemistry National Demonstration Centre for Experimental Chemistry EducationYanbian UniversityYanji 133002China China National Nuclear Corporation Key Laboratory on Uranium Extraction from Seawater Beijing Research Institute of Chemical Engineering and MetallurgyBeijing 101149China

In this study,the ZIF-8 membrane(ZIF-8/PP-g-MAH)is prepared by in situ synthesis of ZIF-8 on irradiation-pretreated polymer substrates to improve the uranium adsorption performance and address the recycling problems of ZIF-8 *** effects of pH,contact time,and uranium concentration on the adsorption of ZIF-8/PP-g-MAH were *** isotherm and kinetics analysis show that ZIF-8/PP-g-MAH has a high adsorption capacity of 478.5 mg/g,which is 1.26 times higher than that of ZIF-8,and a rapid adsorption equilibrium of 120 min,which is shortened to one-third of that required for ZIF-8(360 min).The adsorption process of ZIF-8/PP-g-MAH is consistent with that of the Langmuir isotherm and pseudo-second-order dynamic ***-8/PP-g-MAH also exhibits good selectivity for uranium in simulated *** high adsorption performance of ZIF-8/PP-g-MAH is attributed to its membrane structure,which improves the utilization of coordination sites,including Zn-OH,C-N,and C=*** study provides an efficient adsorption material for rapid uranium extraction,thus promoting the development of uranium extraction technologies.

关键词： ZIF-8 Membrane Uranium Adsorption

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Structural Elucidation of the Polymeric Condensed Tannins of Acacia nilotica Subspecies by ^(13)C NMR, MALDI-TOF and TMA as Sources of Bioadhesives

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Journal of Renewable Materials 2024年第7期12卷 1291-1310页

作者： Zeinab Osman Antonio Pizzi Bertrand Charrier institute of Engineering Research and Materials Technology National Center for ResearchP.O.Box 2404KhartoumSudan ENSTIB-LERMAB University of Lorraine27 rue Philippe SeguinEpinal88000France Department of Materials Science and Engineering Institute of Analytical Sciences and Physico-Chemistry for the Environment and Materials-Xylomat(IPREM-UMR5254)University of Pau and the Adour RegionE2S UPPACNRSMont de Marsan40004France

Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood *** extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atﬁrst to compare their *** tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder *** solutions(47%)were tested by both MALDI ToF,*** thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different *** gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract ***,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,*** 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ***(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence ofﬂavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or *** revealed that the three types of tannins had high MOE at their initial pH(5).

关键词： Acacia nilotica condensed tannins procyanidins prodelphinidins 13C NMR MALDI-ToF

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Association of resting heart rate and hypertension stages on all-cause and car- diovascular mortality among elderly Koreans： the Kangwha Cohort Study

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Journal of Geriatric Cardiology 2016年第7期13卷 573-579页

作者： Mikyung Ryu Gombojav Bayasgalan Heejin Kimm Chung Mo Nam Heechoul Ohrr institute on Aging Ajou University Medical Center Suwon South Korea College of Physical education Kyonggi University Suwon South Korea Department of Public Health the Graduate School Yonsei University Seoul South Korea Department of Epidemiology and Health promotion Institute for Health Promotion Graduate School of Public Health Yonsei University Seoul South Korea Department of Preventive Medicine Yonsei University College of Medicine Seoul South Korea

Background Elevated resting heart rate and hypertension independently increase the risk of mortality. However, their combined ef- fect on mortality in stages of hypertension according to updated clinical guidelines among dderly population is unclear. Methods We fol- lowed a cohort of 6100 residents （2600 males and 3500 females） of Kangwha County, Korea, ranging from 55 to 99 year-olds as of March 1985, for all-cause and cardiovascular mortality for 20.8 years until December 31, 2005. Mortality data were collected through telephone calls and visits （to 1991）, and were confirmed by death record matching with the National Statistical Office （1992-2005）. Hazard ratios were calculated for all-cause and cardiovascular mortality by resting heart rate and hypertension defined by Eighth Joint National Committee crite- ria using the Cox proportional hazard model after controlling for confounding factors. Results The hazard ratios associated with resting heart rate 〉 80 beats/min were higher in hypertensive men compared with normotensives with heart rate of 61-79 beats/rain, with hazard ratios values of 1.43 （95% CI： 1.00-1.92） on all-cause mortality for prehypertension, 3.01 （95% CI： 1.07-8.28） on cardiovascular mortality for prehypertension, and 8.34 （95% CI： 2.52-28.19） for stage 2 hypertension. Increased risk （HR： 3.54, 95% CI： 1.16-9.21） was observed among those with both a resting heart rate 〉 80 beats/rain and prehypertension on cardiovascular mortality in women. Conclusions Indi- viduals with coexisting elevated resting heart rate and hypertension, even in prehypertension, have a greater risk for all-cause and cardiovas- cular mortality compared to those with elevated resting heart rate or hypertension alone. These findings suggest that elevated resting heart rate should not be regarded as a less serious risk factor in elderly hypertensive patients.

关键词： Cardiovascular diseases Heart rate Hypertension Mortality Prehypertension

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Uniform single atomic Cu1-C4 sites anchored in graphdiyne for hydroxylation of benzene to phenol

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National Science Review 2022年第9期9卷 238-245页

作者： Jia Yu Changyan Cao Hongqiang Jin Weiming Chen Qikai Shen Peipei Li Lirong Zheng Feng He Weiguo Song Yuliang Li Beijing National Laboratory for Molecular Sciences CAS ResearchEducation Center for Excellence in Molecular Sciences Key Laboratory of Molecular Nanostructures and NanotechnologyInstitute of ChemistryChinese Academy of Sciences university of Chinese Academy of Sciences Beijing Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of Sciences Beijing National Laboratory for Molecular Sciences CAS ResearchEducation Center for Excellence in Molecular Sciences Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of Sciences

For single-atom catalysts(SACs),the catalyst supports are not only anchors for single atoms,but also modulators for geometric and electronic structures,which determine their catalytic *** an appropriate support to prepare SACs with uniform coordination environments is critical for achieving optimal performance and clarifying the relationship between the structure and the property of *** such a goal is still a significant *** advantage of the strong d-π interaction between Cu atoms and diacetylenic in a graphdiyne(GDY) support,we present an efficient and simple strategy for fabricating Cu single atoms anchored on GDY(Cu1/GDY) with uniform Cu1-C4single sites under mild *** Cu atomic structure was confirmed by combining synchrotron radiation X-ray absorption spectroscopy,X-ray photoele ctron spectroscopy and density functional theory(DFT)*** as-prepared Cu1/GDY exhibits much higher activity than state-of-the-art SACs in direct benzene oxidation to phenol with H2O2reaction,with turnover frequency values of 251 h-1at room temperature and 1889 h-1at 60℃,***,even with a high benzene conversion of86%,high phenol sele ctivity(96 %) is maintaine d,which can be ascribed to the hydrophobic and oleophyllic surface nature of Cu1/GDY for benzene adsorption and phenol *** experiments and DFT calculations indicate that Cu1-C4single sites are more effective at activating H2O2to form Cu=O bonds,which are important active intermediates for benzene oxidation to phenol.

关键词： single-atom catalysis graphdiyne copper benzene oxidation phenol

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Cellulose Acetate Thermoplastics with High Modulus, Dimensional Stability and Anti-migration Properties by Using CA-g-PLA as Macromolecular Plasticizer

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Chinese Journal of Polymer Science 2020年第10期38卷 1141-1148页

作者： Ru-Meng Xu Tian-Tian Yang Elvira Vidovi? Ruo-Nan Jia Jin-Ming Zhang Qin-Yong Mi Jun Zhang CAS Key Laboratory of Engineering Plastics CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences (CAS) university of Chinese Academy of Sciences Faculty of Chemical Engineering and Technology University of Zagreb

Cellulose diacetate(CDA) can be melt-processed to produce numerous and widely-used plastic ***,due to the high glass transition temperature(Tg) of CDA,the addition of up to 30 wt% of micromolecular plasticizers is indispensable,which significantly reduces the dimensional stability and raises safety concerns from the migration of *** this work,a series of CDA-graft-poly(lactic acid)(CDA-gPLA) copolymers were synthesized by ring-opening polymerization of lactide onto the hydroxyl groups of *** resultant CDA-g-PLA copolymers possess adjustable degrees of substitution(DSPLA) and side chain length(DPPLA) by controlling the reaction time and feed *** Tgs and thermal flow temperatures(Tfs) of CDA-g-PLA strongly depend on DPPLA,such as the Tgs decrease linearly with the increase of *** CDA-g-PLA copolymers with the DPPLAof 3-9 can be directly processed to transparent plastics by melt processing without any external plasticizers,because of their low Tfs of 170-215 ℃.More impressively,the CDA-g-PLA can act as the macromolecular *** obtained CDA/CDA-g-PLA has higher storage modulus,flexural modulus and Young’s modulus than the commercial CDA plasticized with triethyl *** addition,the CDA/CDA-g-PLA exhibits high dimensional stability and anti-migration *** a long-term treatment at 80℃ and 60% humidity,the CDA/CDA-g-PLA can retain the initial ***,this work not only proposes a facile method for achieving a direct thermoplastic processing of CDA,but also provides a macromolecular plasticizer for CDA to make lightweight,stable and safer biobased thermoplastics.

关键词： Cellulose diacetate Thermoplastic processing Macromolecular plasticizer Poly(lactic acid)

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Assessing mariculture water quality with the structural and functional characteristics of a ciliate community

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Chinese Journal of Oceanology and Limnology 2011年第1期29卷 128-135页

作者：李继秋许恒龙林晓凤 AL-RASHEID Khaled A.S. Laboratory of Protozoology Key Laboratory of Ecology and Environmental Science in Guangdong Higher EducationSouth China Normal University Laboratory of Protozoology Institute of Evolution and Marine biodiversityOcean University of China Zoology Department King Saud University

Ciliated protozoa play important roles in micro-ecosystems, especially in marine biotopes. However, few studies have been carried out on the periphytic, or aufwuch, forms in mariculture waters so far. In this study, we sampled periphytic ciliate communities in two closed mariculture ponds (ponds CP1 and CP2) and a natural seawater reservoir (pond RP) using a glass slide method to evaluate their colonizing processes and general ecological features, as well as their application as water quality indicators. We analyzed species compositions, structural parameters (species number, richness, diversity, evenness, abundance and dBP) and functional parameters (G, Seq and T90%). Pond RP was characterized by higher levels of structural parameters (except for abundance and dBP) and more equal proportion of the major taxonomic groups. The values of Seq were significantly higher in pond RP and similar in both pond CP1 and CP2. It was also demonstrated that environmental factors, including NO2-H, NO3-H, NH3-H, soluble reactive phosphate, temperature and pH, were the first principal factors affecting the communities. Among them, temperature and chemical factors were all significantly and negatively correlated with species number (P<0.01), richness (P<0.01), diversity (P<0.01), and positive correlated with abundance (P<0.01). Opposite correlations between pH and structural parameters were observed. This study showed that there were significant differences in species composition, structural parameters and functional parameters of the periphytic ciliate communities among the ponds, which were in agreement with the water quality. Results of this study confirmed the periphytic ciliate communities to be useful bioindicators of water quality in intensive mariculture waters.

关键词： periphytic ciliates community structure environmental factors bioindicators

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Magnetic rotation in Rubidium-84

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Nuclear Science and Techniques 2013年第3期24卷 61-65页

作者： SHEN Shuifa HAN Guangbing WEN Shuxian YAN Yupeng WU Xiaoguang ZHU Lihua HE Chuangye LI Guangsheng institute of Nuclear Energy Safety Technology Chinese Academy of Sciences School of Physics Suranaree University of Technology Thailand Center of excellence in Physics (ThEP) Commission on Higher Education State Key Laboratory of Nuclear Physics and Technology (Peking university) School of Physics Shandong University China institute of Atomic Energy P. O. Box 275(10) School of Physics and Nuclear Energy Engineering Beihang University

High-spin states in 84 Rb have been studied by using the 70Zn(18O, p3n)84Rb reaction at beam energy of 75MeV. Three regular magnetic dipole bands including strong M1 and weak E2 transitions have been observed in this nucleus which shows the characteristic feature of magnetic rotation. These bands are interpreted in the projected shell model for the first time on the basis of the four-quasiparticle configuration of the type π(fp)π(g29/2)v(g9/2). It is shown that the calculated sequence lies roughly in the same energy range as the experimental one but the interval between neighboring levels is larger than the corresponding experimental value. We believe that a 4-quasiparticle band crossing with the 2-quasiparticle band will depress the energies of the states.

关键词：磁旋转电子束能量投影壳模型高自旋态磁偶极子 E2跃迁能量范围时间间隔

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A Review of Various Sources of Chitin and Chitosan in Nature

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Journal of Renewable Materials 2022年第4期10卷 1097-1123页

作者： Benedict Terkula Iber Nor Azman Kasan Donald Torsabo Jenifer Wese Omuwa higher Institution Center of excellence(HICoE) Institute of Tropical Aquaculture and FisheriesUniversiti Malaysia TerengganuKuala Nerus21030Malaysia Department of Fisheries and Aquaculture Joseph Sarwuan Tarka University MakurdiMakurdi2373Nigeria

Chitin was first discovered by its name from the Greek word“chiton”,which means“mail coat”.It is indeed a polysaccharide made up of naturally occurring acetyl-D-glucosamine *** was the first researcher who extracted chitin from the shells of mollusks(crabs and lobsters),prawns,and crayfish in *** in 1811,Henri Braconnot discovered chitin in the cell walls of mushrooms and called it“fungine”.Chitin and chitosan are abundant in the biosphere as essential components of many organisms’exoskeletons and as by-products of the global seafood *** biopolymer must be deacetylated before chitosan can be *** can also be extracted using microbes in a biological extraction *** development of products that take advantage of the bioactivities of the existing primary commercial source of chitin(crustacean)has lagged ***,the disadvantages of the present commercial source such as seasonality and competition for other uses among others has been one of the driving forces towards seeking alternative sources of chitin and chitosan in *** review highlights some of the efforts made by environmental scholars to locate possible commercial sources of chitin and chitosan in nature over time.

关键词： Chitin chitosan crustaceans insects fungi

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