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杉木苗期施氮对二年生生长的影响

福建林学院学报 1989年第3期9卷 303-309页

作者：范少辉俞新妥杉木研究所

为了研究杉木苗期施氮的后期效应,我们在盆栽条件下对一年生杉苗按0.0、0.4、0.8、1.2、1.6、2.0g氮/盆6个水平进行施肥,结果表明:苗期施用氮肥对二年生杉苗的生长仍有十分显著的影响,二年生杉苗的苗高、地径、生物量(干重)积累、分枝... 详细信息

为了研究杉木苗期施氮的后期效应,我们在盆栽条件下对一年生杉苗按0.0、0.4、0.8、1.2、1.6、2.0g氮/盆6个水平进行施肥,结果表明:苗期施用氮肥对二年生杉苗的生长仍有十分显著的影响,二年生杉苗的苗高、地径、生物量(干重)积累、分枝数、分枝总长等各项生长指算随施氮水平的变化趋势均与一年生时相似;H/D值、T/R值与根、茎、叶占全苗比重等各项比例在不同的施氮水平之间有著差异,但在一年生和二年生之间无显著差异;当仅以苗高、地径、根长来评价其二年生生长效应时,可以认为苗期施氮无效,但综合生物量枳累和分枝特性指算,施氮的效应显著。

关键词：杉木苗期施肥氮肥二年生生长后期后长肥效

Estimating upper stem diameters and volume of Douglas-fir and Western hemlock trees in the Pacific northwest

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Forest Ecosystems 2018年第3期5卷 199-210页

作者： Krishna P.Poudel Hailemariam Temesgen Andrew n.Gray Department of Forest Engineering Resources and Management College of Forestry Oregon State University USDA Forest Service PNW Research Station

Background: Volume and taper equations are essential for obtaining estimates of total and merchantable stem volume. Taper functions provide advantages to merchantable volume equations because they estimate diameter inside or outside bark at specific heights on the stem, enabling the estimation of total and merchantable stem volume, volume of individual logs, and a height at a given ***: Using data collected from 1218 trees(1093 Douglas-fir(Pseudotsuga menziesii(Mirbel) Franco) and 125 western hemlock(Tsuga heterophylla)), we evaluated the performance of one simple polynomial function and four variable-exponent taper functions in predicting upper stem diameter. Sample trees were collected from different parts of the states of Oregon, Washington, and California. We compared inside-bark volume estimates obtained from the selected taper equation with estimates obtained from a simple logarithmic volume equation for the data obtained in this study and the equations used by the Forest Inventory and Analysis program in the Pacific northwest(FIA-PnW) in the state of California and western half of the states of Oregon and ***: Variable exponent taper equations were generally better than the simple polynomial taper *** FIA-PnW volume equations performed fairly well but volume equations with fewer parameters fitted in this study provided comparable results. The RMSE obtained from taper-based volume estimates were also comparable with the RMSE of the FIA-PnW volume equations for Douglas-fir and western hemlock trees ***: The taper equations fitted in this study provide added benefit to the users over the FIA-PnW volume equations by enabling the users to predict diameter at any height, height to a given diameter, and merchantable volume in addition to cubic volume including top and stump(CVTS) of Douglas-fir and western hemlock trees in the Pacific northwest. The findings of this study also give more confidence to the use

关键词： Pacific northwest Biomass equations Utilization standards Diameter inside bark

Water-soluble-template-derived nanoscale silicon nano- flake and nano-rod morphologies： Stable architectures for lithium-ion battery anodes

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nano Research 2017年第12期10卷 4284-4297页

作者： Bharat Gattu Prashanth Hanumantha Jampani Moni Kanchan Datta Ramalinga Kuruba Prashant n. Kumta Department of Chemical and Petroleum Engineering University of Pittsburgh Pittsburgh PA 1526 I USA Department of Mechanical Engineering and Materials Science University of Pittsburgh Pittsburgh PA 15261 USA Department of Bioengineering University of Pittsburgh Pittsburgh PA 1526 I USA Center for Complex Engineered Multifunctional Materials (CCEMM) University of Pittsburgh PA 15261 USA

Earth abundant and economical rock salt （naC1） particles of different sizes （〈3 μm and 5-20 μm） prepared by high energy mechanical milling were used as water-soluble templates for generation of Si with novel nanoscale architectures via low pressure chemical vapor deposition （LPCVD）. Si nanoflakes （SinF） comprising largely amorphous Si （a-Si） with a small volume fraction of nanocrystalline Si （nc-Si）, and Si nanorods （SinR） composed of a larger volume fraction of crystalline Si （c-Si） and a small volume fraction of a-Si resulted from modification of the naCI crystals. SinF yielded first-cycle discharge and charge capacities of -2,830 and 2,175 mAh.g-1, respective134 at a current rate of 50 mA.g-1 with a first-cycle irreversible loss （fir loss） of -15%-20%. SinR displayed first-cycle discharge and charge capacities of -2,980 and -2,500 mAh-g-1, respectively, at a current rate of 50 mA-g-1 with an fir loss of -12%-15%. However, at a current rate of 1 A.g-1, SinF exhibited a stable discharge capacity of -810 mAh-g-1 at the end of 250 cycles with a fade rate of -0.11% loss per cycle, while SinR showed a stable specific discharge capacity of -740 mAh.g-1 with a fade rate of -0.23% loss per cycle. The morphology of the nanostructures and compositions of the different phases/phase of Si influence the performance of SinF and SInK, making them attractive anodes for lithium-ion batteries.

关键词： silicon nanoflakes nanorods water-soluble template naC1

Vegetation Geo-climatic Zonation in the Rocky Mountains, northern Utah, USA

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Journal of Mountain Science 2014年第3期11卷 656-673页

作者： Antonin KUSBACH Helga VAn MIEGROET Janis L.BOETTInGER James n.LOnG Department of Wildland Resources and Ecology Center Utah State University Utah State University Department of Forest Botany Dendrology and Geobiocoenology Mendel University in Brno

We developed a vegetation geo-climatic zonation incorporating the zonal concept, gradient and discriminant analysis in Wasatch Range, northern Utah, USA. Mountainous forest ecosystems were sampled and described by vegetation, physiographic features and soil properties. The Snowpack Telemetry and national Weather Service Cooperative Observer Program weather station networks were used to approximate the climate of sample plots. We analysed vegetation and environmental data using clustering, ordination, classification, and AnOVA techniques to reveal environmental gradients affecting a broad vegetation pattern and discriminate these gradients. The specific objective was to assess and classify the response of the complex vegetation to those environmental factors operating at a coarse-scale climatic level. Ordination revealed the dominant role of regional, altitude-based climate in the area. Based on vegetation physiognomy, represented by five tree species, climatic data and taxonomic classification of zonal soils, we identified two vegetation geo-climatic zones:(1) a montane zone, with Rocky Mountain juniper and Douglas-fir; and(2) a subalpine zone, with Engelmann spruce and subalpine fir as climatic climax species. Aspen was excluded from the zonation due to its great ecological amplitude. We found significant differences between the zones in regional climate and landformgeomorphology/soils. Regional climate was represented by elevation, precipitation, and air and soil temperatures; and geomorphology by soil types. This coarse-scale vegetation geo-climatic zonation provides a framework for a comprehensive ecosystem survey, which is missing in the central Rocky Mountains of the United States. The vegetation-geoclimatic zonation represents a conceptual improvement on earlier classifications. This framework explicitly accounts for the influence of the physical environment on the distribution of vegetation within a complex landscape typical of the central Rocky Mountains an

关键词： Ecological classification Ecosystemsurvey Land classification Zonal concept Vegetation zone Vegetation geo-dimatic zone Climate change

Multitemporal landslide inventory analysis of an intertropical mountain in west-central Mexico——Basis for hazard management

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Journal of Mountain Science 2022年第6期19卷 1650-1669页

作者： Alejandro Cesar VALDES CARRERA Manuel E.MEnDOZA Teodoro CARLÓn ALLEnDE Jose Luis MACIAS Centro de Investigaciones en Geografia Ambiental Universidad Nacional Autonoma de MexicoMorelia 58190Mexico Consejo nacional de Ciencia y Tecnologia-Instituto de Geofisica-Unidad Michoacan Universidad Nacional Autonoma de MexicoMorelia 58190Mexico Instituto de Geofisica-Unidad Michoacan Universidad Nacional Autonoma de MexicoMorelia 58190Mexico

Landslides in intertropical mountainous areas of Mexico are a natural hazard that could potentially generate a disaster. Despite this, many areas lack landslide inventories, making it difficult to monitor and efficiently manage the associated risks for local populations. For this reason, the aim of this research was to undertake a multitemporal landslide inventory and analyze its conditioning factors in the Pico de Tancítaro stratovolcano, which, in recent decades, has presented several high-risk geomorphological events with disastrous consequences for nearby localities. The spatial distribution of landslides and its conditioning factors were mapped at a 1:50,000 scale for the 1995-2020 period, through visual interpretation of orthophotos and satellite images(Landsat, SPOT, and SEnTInEL). The conditioning factors that link the most to landslides were Quaternary andesite and basaltic andesite rocks;volcanic cones, mountain river valleys, and very steep to steep slopes(30° to >45°), oriented to the South, north, and East;Andosols and Leptosols;and the oyamel fir and mixed forests. 505 landslide events classified into slides and flows that occurred in 1995, 2004, 2010, and 2015 were identified. new scars generated by the reactivation of landslide processes were also observed. The landslides in the study area were triggered by torrential rains caused by hurricanes and tropical storms;such as hurricanes Alex and Patricia. The inventory and analysis of conditioning factors highlighted the distribution and dynamics of slides and flows in the study area. In addition, the most important factors for studies of landslide susceptibility, hazards, and risks in the Pico de Tancítaro stratovolcano were identified, contributing to the management of geomorphological risks in intertropical mountain areas.

关键词： Geomorphology Mass wasting natural hazards Pico de Tancítaro stratovolcano Risk management

Experimental Investigation of Pyrolysis Process of Woody Biomass Mixture

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Journal of Thermal Science 2014年第3期23卷 290-296页

作者： Tijana R.Kosanic Mirjana B.Ceranic Slavko n.Duric Vojin R.Grkovic Milan M.Milotic Sasa D.Brankov Faculty of Technical Sciences University of Novi SadRepublic of Serbia Faculty of Transport and Traffic Engineering University of East SarajevoDoboj Bosnia and Herzegovina

This paper describes an experimental investigation of pyrolysis of woody biomass mixture. The mixture consists of oak, beech, fir, cherry, walnut and linden wood chips with equal mass fractions. During the experiment, the sample mass inside the reactor was 10 g with a particle diameter of 5-10 mm. The sample in the reactor was heated in the temperature range of 24-650℃. Average sample heating rates in the reactor were 21, 30 and 54 ℃/min. The sample mass before, during and after pyrolysis was determined using a digital scale. Experimental results of the sample mass change indicate that the highest yield of pyrolytic gas was achieved at the temperature slightly above 650℃ and ranged from 77 to 85%, while char yield ranged from 15 to 23%. Heating rate has sig- nificant influence on the pyrolytic gas and char yields. It was determined that higher pyrolysis temperatures and heating rates induce higher yields of pyrolytic gas, while the char mass reduces. Condensation of pyrolytic gas at the end of the pyrolysis process at 650℃ produced 2.4-2.72 g of liquid phase. The results obtained represent a starting basis for determining material and heat balance of pyrolysis process as well as woody biomass pyrolysis equipment.

关键词： pyrolysis woody biomass mixture pyrolysis temperature gas yield

TEMPERATURE DEPEnDEnCE OF fir LASER OUTPUT POWER

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TEMPERATURE DEPENDENCE OF FIR LASER OUTPUT POWER

Deep learning model for estimating the mechanical properties of concrete containing silica fume exposed to high temperatures

International Conference on Millimeter Wave and far-Infrared Technology

作者： L.n.Orlov Institute of Physics BSSR Academy of Sciences Leninsky prospect 70 Minsk 220602 USSR

＜正＞ Results of computer modeling of the optically pumped far infrared molecular laser output power and the calculations of its dependence on gas temperature for various laser lines are presented.

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1316-1330页

作者： Harun TAnYILDIZI Abdulkadir SEnGUR Yaman AKBULUT Murat SAHtna Faculty of Technology Department of Civil EngineeringFirat UniversityElazig 23100Turkey Faculty of Technology Department of Electrical-Electronics EngineeringFir at UniversityElazig 23100Turkey

In this study,the deep learning models for estimating the mechanical properties of concrete containing silica fume subjected to high temperatures were *** fume was used at concentrations of 0%,5%,10%,and 20%.Cube specimens(100 mm×100 mm×100 mm)were prepared for testing the compressive strength and ultrasonic pulse *** were cured at 20℃zb2℃ in a standard cure for 7,28,and 90 *** curing,they were subjected to temperatures of 20℃,200℃,400℃,600℃,and 800℃.Two well-known deep learning approaches,i.e.,stacked autoencoders and long short-term memory(LSTM)networks,were used for forecasting the compressive strength and ultrasonic pulse velocity of concrete containing silica fume subjected to high *** forecasting experiments were carried out using MATLAB deep learning and neural network tools,*** statistical measures were used to validate the prediction performances of both the *** study found that the LSTM network achieved better results than the stacked *** addition,this study found that deep learning,which has a very good prediction ability with little experimental data,was a convenient method for civil engineering.

关键词： concrete high temperature strength properties deep learning stacked auto-encoders LSTM network

A note on the natural Relocation of <i>Marchalina hellenica</i>(Gennadius) from Pine to fir Trees

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Advances in Entomology 2016年第3期4卷 163-166页

作者： A. E. Tsagkarakis n. G. Emmanouel Laboratory of Agricultural Zoology and Entomology Agricultural University of Athens Athens Greece

Marchalina hellenica (Gennadius) (Hemiptera: Margarodidae) is the most important honeydew producing insect in Greece. It was referred as monophagus, feeding exclusively on pine trees, until 1995 when it was successfully established on fir trees after artificial “inoculation” at Menalo and Helmos mountains. In this scientific note, the first record of natural relocation of M. hellenica from pine to fir trees is referred.

关键词： Marchalina hellenica Honeydew Relocation Abies cephalonica Parnis Oiti Greece