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13C核磁共振（四）

有机化学 1980年第4期 58-64页

作者： von e.breitmaier G·Bauer 陆仁宋王绮文

913C自旋-晶格弛豫时间（T1）的测量及应用 9.1 测定T1的方法 9.1.1 倒向—恢复法此法是用（180°-τ-90°）_n脉冲系列作用于样品。磁化矢量M0在180°脉冲作用下倒向（图20b）,在自旋-晶格弛豫过程中,磁化矢量从-M0经0到+M0弛豫,在这... 详细信息

913C自旋-晶格弛豫时间（T1）的测量及应用 9.1 测定T1的方法 9.1.1 倒向—恢复法此法是用（180°-τ-90°）_n脉冲系列作用于样品。磁化矢量M0在180°脉冲作用下倒向（图20b）,在自旋-晶格弛豫过程中,磁化矢量从-M0经0到+M0弛豫,在这一过程中,即过了时间τ后,90°脉冲将部份弛豫的磁化矢量Mτ旋转到X（?）Y平面中,并在接收线圈中感应出FID信号。如果τ很短,Mτ还是负的（Mτ<0）,90°脉冲（?）1,作用后Mτ沿X向负Y轴旋转（图20c）,

关键词：磁化矢量脉冲作用弛豫时间核自旋顺磁性物质

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13C核磁共振（三）

有机化学 1980年第3期 67-72页

作者： von e.breitmaier G.Bauer 陆仁荣王绮文

8.1 通过一个键的C与H偶合除了化学位移之外,C—H的偶合常数也能提供重要的信息,测量J值时必须取不去偶或用交替脉冲双共振方法。这两种方法都需时较长,并且要求样品量较多。1JCH也可从1H谱的13C卫星线测得。1JCH在120-130Hz之间2J（CH... 详细信息

8.1 通过一个键的C与H偶合除了化学位移之外,C—H的偶合常数也能提供重要的信息,测量J值时必须取不去偶或用交替脉冲双共振方法。这两种方法都需时较长,并且要求样品量较多。1JCH也可从1H谱的13C卫星线测得。1JCH在120-130Hz之间2J（CH）、3J（CH）4J（CH）都小于

关键词：偶合常数化学位移谱线位移反式天然丰度

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13C核磁共振（二）

有机化学 1980年第2期 44-62页

作者： von e.breitmaier G.Bauer 陆仁荣王绮文

4.识别图谱的化学方法 4.1 氘代用化学方法将样品中的某些位置上的氢以重氢（2D）代替之后,与这个氢键接的13C共振峰就发生相应变化,利用这种变化可以识别谱峰。2D的I=1,因此,CD,CD2,CD3的碳顺次表现为三重峰（1:1:1）,五重峰（1:3:5:3:... 详细信息

4.识别图谱的化学方法 4.1 氘代用化学方法将样品中的某些位置上的氢以重氢（2D）代替之后,与这个氢键接的13C共振峰就发生相应变化,利用这种变化可以识别谱峰。2D的I=1,因此,CD,CD2,CD3的碳顺次表现为三重峰（1:1:1）,五重峰（1:3:5:3:1）及七重峰（1:3:5:7:5:3:1）,又由于2D有四极弛豫作用,使13C讯号加宽,这两重原

关键词：化学位移谱线位移取代基常数诱导效应电子效应偏共振去偶杂原子诱导位移样品量溶剂苯甲酮位移常数

Book review “Wattles: Australian Acacia species around the world” by David M. Richardson, Johannes J. Le Roux and elizabete Marchante

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Forest ecosystems 2024年第2期11卷 140-141页

作者： Klaus von Gadow Faculty of Forestry and Forest ecology Georg-August-University GöttingenBüsgenweg 5D-37077GöttingenGermany Department of Forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

In a world of Google and AI, developing an encyclopedic coverage of a theme that is of great interest to biologists, social scientists, politicians and environmental managers, is a daunting challenge. Wattles is a book that presents new knowledge, makes interesting reading, and has the potential to stimulate research in a variety of disciplines. We learn that Acacia, commonly known as the wattles or acacias, is a genus of shrubs and trees comprising 1,083 species of which 417 are known to have been introduced to areas outside their native range. We are surprised to read that Australian acacias are found almost everywhere, in virtually all terrestrial habitats, including woodlands, grasslands, alpine settings,rainforests, coastal dunes and deserts, causing major environmental and socio-economic changes in the invaded regions. Until recently, Acacia comprised a group of plant species native to Africa, South America and Australasia, but the name is now reserved for species predominantly from Australia, including some from Southeast Asia. The genus name Acacia is Neo-Latin, and refers to a preparation extracted from the leaves and fruit pods of Vachellia nilotica, the original type of the genus.

关键词： Richardson outside Latin

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A novel method for the green utilization of waste fried oil

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Particuology 2024年第1期84卷 1-11页

作者： Gan Cheng Mengni Zhang Yang Lu Yanhui Zhang Bin Lin ee von Lau College of Chemistry and Chemical engineering Henan Polytechnic UniversityJiaozuo454003China Henan Key Laboratory for Green and efficient Mining&Comprehensive Utilization of Mineral Resources Henan Polytechnic UniversityJiaozuo454003China Collaborative Innovation Center of Coal Work Safety and Clean High efficiency Utilization Henan Polytechnic UniversityJiaozuo454003China School of engineering Monash University MalaysiaSubang JayaSelangor47500Malaysia

Waste fried oil was studied to prepare three different types of detergent such as soap,liquid soap and soap powder via saponification *** preparation conditions of soap base were optimized by orthogonal *** specific preparation processes included waste fried oil treatment,orange peel extract preparation,saponification,demoulding and *** showed that the optimal con-ditions for saponification were as follows:ratio of pure waste fried oil to coconut oil=6∶4,alkali liquor(NaOH)mass fraction 30%,saponification temperature 70℃,orange peel extract concentration 15%.The mature soap was then used to make liquid soap and soap powder by surfactant(sodium dodecylbenzene sulfonate,coconut diethanol amide)addition,followed by *** prepared detergent conforms to the production standard of strong decontamination ability,possesses stable performance,is gentle to skin and non-toxic.

关键词： Waste fried oil Detergent Saponification Decolorization

Grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,Mexico

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Forest ecosystems 2024年第1期11卷 1-13页

作者： Jaime Roberto Padilla-Martínez Carola Paul Kai Husmann Jose Javier Corral-Rivas Klaus von Gadow Department of Forest economics and Sustainable Land-use Planning Faculty of Forest Sciences and Forest EcologyUniversity of GottingenBüsgenweg 137077GottingenGermany Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Boulevard Durango S/N34120DurangoMexico Faculty of Forestry and Forest ecology Georg-August-UniversitatBüsgenweg 537077GottingenGermany Department of Forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological ***,a greater species diversity presents challenges for forest management and *** study aims to develop basal area growth models for tree species *** analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,***,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster ***,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site *** principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the *** generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak *** developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests.

关键词： Temperate multispecies forests Cluster analysis Basal area increment Generalized additive models

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The evaluation of next-generation probiotics on broiler growth performance,gut morphology,gut microbiome,nutrient digestibility,in addition to enzyme production of Bacillus *** vitro

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Animal Nutrition 2024年第3期18卷 133-144页

作者： Jacoba I.Bromfield Shahram Niknafs Xiaojing Chen Juhani von Hellens Darwin Horyanto Baode Sun Lei Yu Viet Hai Tran Marta Navarro eugeni Roura Bioproton Pty Ltd Acacia RidgeBrisbaneQueenslandAustralia Centre for Nutrition and Food Sciences Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandBrisbaneQueenslandAustralia Centre for Animal Science Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandBrisbaneQueenslandAustralia

Considerable research has been conducted into the efficacy of individual probiotics in broiler production,however information on the most effective combinations of synergistic Bacillus probiotic is *** study investigated the impact of different Bacillus strain combinations in broiler chickens,as well as in vitro enzyme *** experiment one,a total of 576 Ross 308 broilers at 1 d old were grown for 21 d across 6 treatments of maize-soybean diets(n=12 pens per treatment)to compare three different strain combinations(formulation 1[F1]:3 strains Bacillus amyloliquefaciens;F2:Bacillus coagulans and 2 strains ***;F3:***,Bacillus licheniformis and 2 strains ***;F5:Bacillus subtilis,*** and 2 strains ***),positive control(PC),and a negative control antibiotic treatment group(NC).In exp.2,a total of 360 one-day-old ROSS308 broilers were used to test five treatments(n=9)including PC,NC,F1 and F5(selected from exp.1),and F4(Bacillus pumilis and 2 strains ***)in a maize-soybean *** F1 demonstrated a significant improvement in feed conversion ratio(FCR)compared to F2 at d 14(1.49 vs 2.10;P=0.038)and the body weight(BW)at d 21(847.0 g vs 787.4 g)compared to other combinations(P=0.027).The FCR at d 21 tended to be lower in birds fed F1(1.46 vs 1.66)compared to the control(P=0.068).Probiotic treatments had significantly improved nutrient digestibility compared to the PC and ***,probiotic treatments supported the growth of Streptococcus,a common commensal genus and reduced the abundance of genera that correlated with low weight gain such as *** two revealed that F4 improved FCR(Pesting showed a high production of protease and amylase by ***,the addition of Bacillus probiotics,particularly containing *** strains and Bacillus pumilus,into the diet of broiler chickens improves

关键词： Broiler Probiotic Bacillus Gut health Microbial profile

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTLU İsmail e.KILIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

Flame-assisted ultrafast synthesis of functionalized carbon nanosheets for high-performance sodium storage

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Carbon energy 2024年第7期6卷 123-133页

作者： Chen Chen Dong Yan Yew von Lim Lei Liu Xue Liang Li Junjie Chen Tian Chen Li Youyu Zhu Jiangtao Cai Ying Huang Yating Zhang Hui Ying Yang School of Chemistry and Chemical engineering Northwestern Polytechnical UniversityXi'anChina Pillar of engineering Product Development Singapore University of Technology and DesignSingaporeSingapore School of electrical engineering Xi'an University of TechnologyXi'anChina International Joint Laboratory of New energy Materials and Devices of Henan Province School of Physics and ElectronicsHenan UniversityKaifengChina College of Chemistry and Chemical engineering Xi'an University of Science and TechnologyXi'anChina

The unique structural features of hard carbon(HC)make it a promising anode candidate for sodium-ion batteries(SIB).However,traditional methods of preparing HC require special equipment,long reaction times,and large energy consumption,resulting in low throughputs and *** our contribution,a novel synthesis method is proposed,involving the formation of HC nanosheets(NS-CNs)within minutes by creating an anoxic environment through flame combustion and further introducing sulfur and nitrogen sources to achieve heteroatom *** effect of heterogeneous element doping on the microstructure of HC is quantitatively analyzed by high-resolution transmission electron microscopy and image processing *** with density functional theory calculation,it is verified that the functionalized HC exhibits stronger Na^(+)adsorption ability,electron gain ability,and Na^(+)migration *** a result,NS-CNs as SIB anodes provide an ultrahigh reversible capacity of 542.7mAh g^(-1) at 0.1Ag^(-1),and excellent rate performance with a reversible capacity of 236.4mAh g^(-1) at 2Ag^(-1) after 1200 ***,full cell assembled with NS-CNs as the can present 230mAh g^(-1) at 0.5Ag^(-1) after 150 ***,in/ex situ techniques confirm that the excellent sodium storage properties of NS-CNs are due to the construction of abundant active sites based on the novel synthesis method for realizing the reversible adsorption of Na^(+).This work provides a novel strategy to develop novel carbons and gives deep insights for the further investigation of facile preparation methods to develop high-performance carbon anodes for alkali-ion batteries.

关键词： carbon nanosheets heteroatom doping sodium-ion battery sustainable materials