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Research of Mechanical and Thermal Properties of Composite Material Based on Gypsum and Straw

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Journal of Renewable Materials 2022年第7期10卷 1859-1873页

作者： Nikola Vavřínová Kateřina Stejskalová JiříTeslík Kateřina Kubenková JiříMajer Faculty of Civil Engineering VSB-Technical University of OstravaOstrava70800Czech Republic

This article is focused on the investigation of the mechanical and thermal properties of composite material that could be used for the production of plaster or *** composite material is made of gypsum and reinforcing natural *** article verifies whether this natural reinforcement can improve the investigated properties compare. to conventional plasters and gypsum plasterboards made of pure *** this composite material,high-strength plasterboards could then be produced,which meet the higher demands of users than conventional gypsum *** their production,natural waste materials would be used *** part of the development of new building materials,it is necessary to specify essential characteristics for their later use in civil *** wheat straw and three gypsum classes with strengths G2(2 MPa)—gypsum Class I.,G5(5 MPa)—gypsum Class *** G16(16 MPa)—gypsum Class *** used to create the test *** were made with different ratios of the two ingredients,with the percentages of straw being 0%,2.5%,and 5%for each gypsum *** first part of the article describes how the increasing proportion of straw affects the composite’s mechanical properties(flexural strength and compressive strength).The second part of the article focuses on the change of thermal properties(thermal conductivity and specific heat capacity).The last part of the article mentions the verification of the fire properties(single-flame source fire test and gross heat of combustion)of this composite *** research has shown that the increasing proportion of straw reinforcement caused a deterioration in the flexural strength(up to 56.49%in the *** of gypsum Class II.)and compressive strength(up to 80.27%in the *** of gypsum Class III.)and an improvement in the specific heat capacity and thermal conductivity(up to 31.40%in the ***).This composite material is thus not suitable for the production of high-streng

关键词： Composite material gypsum plasterboard crushed straw flexural strength compressive strength thermal conductivity specific heat capacity ignitability gross heat of combustion

Methods for discovery and characterization of cellulolytic enzymes from insects

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Insect Science 2010年第3期17卷 184-198页

作者： Jonathan D. Willis cris Oppert Juan L. Jurat-Fuentes Department of Entomology and Plant Pathology University of Tennessee Knoxville Tennessee USA

Cellulosic ethanol has been identified as a crucial biofuel resource due to its sustainability and abundance of cellulose feedstocks. However, current methods to obtain glucose from lignocellulosic biomass are.ineffective due to recalcitrance of plant biomass. Insects have evolved endogenous and symbiotic enzymes to efficiently use lignocellulosic material as a source of metabolic glucose. Even though traditional biochemical methods have been used to identify and characterize these enzymes, the advancement of genomic and proteomic research tools are.expected to allow new insights into insect digestion of cellulose. This information is highly relevant to the design of improved industrial processes ofbiofuel production and to identify potential new targets for development of insecticides. This review describes the diverse methodologies used to detect, quantify, purify, clone and express cellulolytic enzymes from insects, as well as their advantages and limitations.

关键词： biofuels cellulases cellulase discovery methods cellulase substrate insect digestive fluids lignocellulosic biomass

Halogen-specific total organic halogen analysis： Assessment by recovery of total bromine

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Journal of Environmental Sciences 2017年第8期29卷 340-348页

作者： markus Langsa Sebastien Allard ina Kristiana Anna Heitz Cynthia A.Joll Curtin Water Quality Research Centre Department of Chemistry Curtin University Perth Western Australia 6102 Australia Department of Civil Engineering Curtin University Perth Western Australia 6102 Australia Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan AlamUniversitas PapuaManokwaripapua Barat 98314Indonesia

Determination of halogen-specific total organic halogen（TOX） is vital for studies of disinfection of waters containing bromide, since total organic bromine（TOBr） is likely to be more problematic than total organic chlorine. Here, we present further halogen-specific TOX method optimisation and validation, focusing on measurement of TOBr. The optimised halogen-specific TOX method was validated based on the recovery of model compounds covering different classes of disinfection by-products（haloacetic acids, haloacetonitriles,halophenols and halogenated benzenes） and the recovery of total bromine（mass balance of TOBr and bromide concentrations） during disinfection of waters containing dissolved organic matter and bromide. The validation of a halogen-specific TOX method based on the mass balance of total bromine has not previously been reported. Very good recoveries of organic halogen from all model compounds were obtained, indicating high or complete conversion of all organic halogen in the model compound solution through to halide in the absorber solution for ion chromatography analysis. The method was also successfully applied to monitor conversion of bromide to TOBr in a groundwater treatment plant. An excellent recovery（101%）of total bromine was observed from the raw water to the post-chlorination stage. Excellent recoveries of total bromine（92%–95%） were also obtained from chlorination of a synthetic water containing dissolved organic matter and bromide, demonstrating the validity of the halogen-specific TOX method for TOBr measurement. The halogen-specific TOX method is an important tool to monitor and better understand the formation of halogenated organic compounds, in particular brominated organic compounds, in drinking water systems.

关键词： Total organic bromine Dissolved organic matter Bromide Chlorination Drinking water Health effects

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数字游民:追求工作和休闲的全面自由

工会理论研究 2024年第2期 71-79页

作者：伊娜·赖兴伯格姚建华徐偲骕(编译) 新西兰惠灵顿维多利亚大学旅游管理学系复旦大学新闻学院复旦大学马克思主义新闻观教学与研究基地上海大学新闻传播学院上海大学中国当代文化研究中心

数字游民群体主要由年轻的专业人士组成,他们从事线上工作并将旅行融入日常生活。这种生活方式打破了传统的居住和工作地点的限制,工作、休闲和旅行之间的界限也随之变得模糊。本文旨在界定“数字游民”这一概念,探讨该群体选择数字游... 详细信息

数字游民群体主要由年轻的专业人士组成,他们从事线上工作并将旅行融入日常生活。这种生活方式打破了传统的居住和工作地点的限制,工作、休闲和旅行之间的界限也随之变得模糊。本文旨在界定“数字游民”这一概念,探讨该群体选择数字游牧的动机,以及如何将这些动机付诸实践。数字游民追求一种以全面自由为特征的整体性生活方式,力图实现职业自由、空间自由和个人自由。在理想状态下,他们将工作看作是一种源自内部动机的活动,它并不比休闲低等,更不仅仅是一种个人不得不履行的责任。同时,尽管休闲(包括旅行)是这种生活方式给人以积极体验的重要来源,它也带来了不少挑战,因此本质上还是一种不同形态的工作。

关键词：数字游民整体性生活方式工作休闲自由

Improved allometric equations for tree aboveground biomass estimation in tropical dipterocarp forests of Kalimantan,Indonesia

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Forest Ecosystems 2017年第2期4卷 83-92页

作者： Solichin Manuri cris Brack Fatmi Noor'an Teddy Rusolono Shema Mukti Anggraini Helmut Dotzauer Indra Kumara Fenner School of Environment and Society The Australian NationalUniversityLinnaeus Way Building 141Canberra ACT2601Australia Dipterocarps Research Center Forest Research Development and Innovation AgencyMinistry of Environment and ForestryJl.AW SyahraniSamarindaEast KalimantanIndonesia Faculty of Forestry Bogor Agricultural UniversityJl Raya DarmagaKampus IPBBogor 16680Indonesia Forests and Climate Change Program Deutsche Gesellschafc fur Internationale Zusammenarbeit(FORCLIME-GIZ)Manggala Wanabakti BuildingBlock VII6th floorJakartaIndonesia Biodiversity and Climate Change Program Deutsche Gesellschafr fur Internationale Zusammenarbeit(BIOCLIME-GIZ)Manggala Wanabakti BuildingBlock VIL 6th floorJakartaIndonesia District Forestry and Plantation Service Jl.Antasarl No 4 Putussibaa Kapuas Hulu 78711West KalimantanIndonesia

Background： Currently, the common and feasible way to estimate the most accurate forest biomass requires ground measurements and allometric *** studies have been conducted on allometric equations development for estimating tree aboveground biomass（AGB） of tropical dipterocarp forests（TDFs） in Kalimantan（Indonesian Borneo）.However, before the use of existing equations, a validation for the selection of the best allometric equation is required to assess the model bias and *** study aims at evaluating the validity of local and pantropical equations; developing new allometric equations for estimating tree AGB in TDFs of Kalimantan; and validating the new equations using independent ***： We used 108 tree samples from destructive sampling to develop the allometric equations, with maximum tree diameter of 175 cm and another 109 samples from previous studies for validating our *** performed ordinary least square. linear regression to explore the relationship between the AGB and the predictor variables in the natural logarithmic ***： This study found that most of the existing local equations tended to be biased and imprecise, with mean relative error and mean absolute relative error more than 0.1 and 0.3, *** developed new allometric equations for tree AGB estimation in the TDFs of *** a validation using an independent dataset,we found that our equations were reliable in estimating tree AGB in *** pantropical equation, which includes tree diameter, wood density and total height as predictor variables performed only slightly worse than our new ***： Our equations improve the precision and reduce the bias of AGB estimates of *** models developed from small samples tend to systematically bias.A validation of existing AGB models is essential before the use of the models.

关键词： Allometric equation Local and pantropical models AGB Model validation Destructive sampling Tropical dipterocarp forest

Biased dispersal of Metrioptera bicolor, a wing dimorphic bush-cricket

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Insect Science 2018年第2期25卷 297-308页

作者： ina Monika margret Heidinge Silke Hein Heike Feldhaar Hans-Joachim Poethke Field Station Fabrikschleichach University of W（Jrzburg Rauhenebrach Germany W~sseri 8 CH-8816 Hirzel Switzerland Department of Animal Ecology I University of Bayreuth Bayreuth Germany Bavarian State Institute for Viticulture and Horti- culture Bee Research Center An der Steige 15 97206 VeitshSchheim Germany

In the highly fragmented landscape of central Europe, dispersal is of particular importance as it determines the long-term survival of animal populations. Dispersal not only secures the recolonization of patches where populations went extinct, it may also rescue small populations and thus prevent local extinction events. As dispersal involves different individual fitness costs, the decision to disperse should not be random but context- dependent and often will be biased toward a certain group of individuals （e.g., sex- and wing morph-biased dispersal）. Although biased dispersal has far-reaching consequences for animal populations, immediate studies of sex- and wing morph-biased dispersal in orthopterans are.very rare. Here, we used a combined approach of morphological and genetic analyses to investigate biased dispersal of Metrioptera bicolor, a wing dimorphic bush-cricket. Our results clearly show wing morph-biased dispersal for both sexes of M. bicolor. In addition, we found sex-biased dispersal for macropterous individuals, but not for micropters. Both, morphological and genetic data, favor macropterous males as dispersal unit of this bush-cricket species. To get an idea of the flight ability ofM. bicolor, we compare. our morphological data with that of Locusta migratoria and Schistocerca gregaria, which are.very good flyers. Based on our morphological data, we suggest a good flight ability for macropters of M. bicolor, although flying individuals of this species are.seldom observed.

关键词： aspect ratio dispersal traits flight muscle ratio Metrioptera bicolor sex-biased dispersal wing load wing morph-biased dispersal

Developmental abnormalities and growth patterns in juvenile Oreochromis mossambicus chronically exposed to efavirenz

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Emerging Contaminants 2022年第1期8卷 83-89页

作者： Saisha Kowlaser Irene Barnhoorn ina Wagenaar Department of Zoology University of JohannesburgAuckland ParkSouth Africa Department of Biological Sciences University of VendaThohoyandouSouth Africa

Efavirenz is an antiretroviral drug(ARV)used for the treatment of Human Immunodeficiency Virus(HIV/AIDS)*** effects efavirenz may have on mammals is known,however,little is known about the effects on non-target aquatic organisms,especially on growth and development of *** Oreochromis mossambicus were bred to produce newly fertilised *** eggs were exposed to efavirenz using two concentrations(10.3 ng/L and 20.6 ng/L)over 60 days growth *** growing juveniles were kept in a static renewal system under controlled laboratory conditions(27±1℃;day:night photoperiod of 14:10)to simulate an optimal growth environment similar to *** endpoints included changes in growth,growth rates and morphological development based on exposure to *** morphological analyses were done at(i)1-day post hatching,(ii)approximately two weeks post hatching,(iii)30 days post hatching and(iv)60 days post hatching abnormalities were *** had no noticeable effect on length and weight,or growth parameters of the juveniles at all *** however,influenced the morphological development of the juveniles by causing physical abnormalities(p>0.05).Abnormalities included spinal deformities and alterations to the shape of the jaws.

关键词： exposed juvenile alterations

Seasonality of PSII thermostability and water use e ffi ciency of in situ mountainous Norway spruce(Picea abies)

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Journal of Forestry Research 2023年第1期34卷 197-208页

作者： Peter Petrik Anja Petek-Petrik Alena Konopkova Peter Fleischer Srdjan Stojnic ina Zavadilova Daniel Kurjak Global Change Research Institute Czech Academy of SciencesBrnoCzech Republic Department of Vegetation Ecology Institute of Botany CASBrnoCzech Republic Faculty of Forestry Technical University of ZvolenZvolenSlovakia Institute of Forest Ecology Slovak Academy of SciencesZvolenSlovakia Institute of Lowland Forestry and Environment University of Novi SadNovi SadSerbia

The stability of monocultural,even-aged spruce forests at lower altitudes in Central Europe is seriously threatened by the prospects of global climate *** thermostability and water use efficiency of their photo synthetic apparatus might play a vital role in their successful *** this study,photo systemⅡ(PSⅡ)performance(OJIP transient,rapid light curves)and thermostability were analyzed in Norway spruce(Picea abies(L.)Karst.)throughout the growing season of the exceptionally warm year 2018(May-September)in the Western Carpathians,*** measurements were accompanied by analysis of pigment concentrations in the *** addition,gas-exchange temperature curves were produced weekly from June until September to obtain intrinsic water use *** the beginning of the growing season,needles exposed to heat stress showed significantly higher basal fluorescence and lower quantum yield,performance index,critical temperature thresholds of PSII inactivation and nonphotochemical yield in comparison to other *** overall thermostability(heat-resistance)of PSII peaked in July and August,reflected in the lowest basal fluorescence and the highest quantum yield of PSII,critical temperature thresholds and yield of non-photochemical quenching under heat ***,the ratio between chlorophyll and carotenoids was the highest in August and had a positive impact on PSII ***,the high-temperature intrinsic water use efficiency was significantly higher during July and August than in *** show that15-year-old trees of Picea abies at 840 m *** acclimative seasonal responses of PSII thermostability and intrinsic water use efficiency during an exceptionally warm *** results suggest that mountainous *** at lower altitudes can acclimate their photosynthetic apparatus to higher temperatures during summer.

关键词： Heat stress Photosynthesis Non-photochemical quenching Pigments Intrinsic water use efficiency

Tumour induced osteomalacia due to a sinonasal hemangiopericytoma:A case report

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World Journal of Clinical Cases 2013年第1期1卷 59-63页

作者： Sophie A Jamal Brendan C Dickson ina Radziunas Division of Endocrinology Department of Medicine University of Toronto Toronto ON M5G 1N8 Canada Department of Pathology Mount Sinai Hospital Toronto ON M5G 1X5 Canada Multidisciplinary Osteoporosis Program Women’s College Hospital Toronto ON M5S 1B1 Canada

Tumour induced osteomalacia(TIO) is a rare.and often unrecognized cause of hypophosphatemia. We report on a case of TIO due to a hemangiopericytoma originating from the left nasal sinus. The patient was a 55-year-old male with a 3-year history of left hip pain and an undisplaced left hip fracture. Biochemical testing demonstrated low levels of serum phosphate and serum 1,25-dihydroxyvitamin D, and an elevated level of fibroblast growth factor 23. Octreotide scanning demonstrated uptake in the left nasal sinus are. and a computed tomography scan revealed a left nasal sinus mass. The patient underwent surgical resection of the mass and histology was consistent with a sinonasal hemangiopericytoma. His serum phosphate levels normalized almost immediately after surgery and he had complete resolution of hip pain. Our case highlights the importance of considering TIO when assessing patients with low serum phosphate.

关键词： Phosphate Osteomalacia Tumour Fibroblast growth factor 23