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Experimental approaches to select tree species for forest restoration:effects of light,water availability and interspecific competition in degraded areas

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Journal of Forestry Research 2022年第4期33卷 1197-1207页

作者： Johanna Croce Ernesto i.badano Carolina b.trigo Fernanda Martinez-Galvez Andrés tálamo Laboratorio de Ecología Aplicada a la Conservación Instituto de Bio y Geociencias del Noroeste ArgentinoConsejo de Investigaciones Científi cas y Técnicas-Universidad Nacional de SaltaAvenida Bolivia 51504400 SaltaArgentina iPiCYt/División de Ciencias Ambientales Instituto Potosino de Investigación Científi ca y TecnológicaCamino a la Presa San José2055Colonia Lomas 4^(a)Sección78216 San Luis PotosíMéxico

Knowing what native trees can recr uit on degraded areas allows selecting the best species to restore these ***,as this information is not often available,experimentation is required before large-scale *** study used ex situ experiments to make these decisions on *** with r-strategist plants,excessive solar radiation and water shortage commonly impair tree recruitment in open *** experiments focused on the interactions among these factors and were conducted with three pioneer species from seasonally dry forests of northwest Argentina,Anadenanthera colubrina,Ceiba chodatii and Jacaranda *** of each species were sown at two light levels(sunlight/shade),two rainfall levels(full/reduced)and two levels of interspecific competition(with/without competitor)in a tree *** emergence and survival were monitored over a year and the results indicate that species differentially respond to varying levels of light and *** of *** tolerated water shortages under elevated solar radiation,which are desirable features for forest *** of *** tolerated shade and drought,suggesting that they require shading for establishing in open ***,*** seedlings neither tolerated full sunlight nor water shortages,suggesting that this species requires shading and regular watering if used in *** of the effects of light and water,the survival of all species was reduced by interspecific *** results highlight the importance of experimentation for selecting the best species for forest restoration and can enhance the cost/benefit ratios of these actions.

关键词： Common-garden experiments Drought Ecological restoration interspecific competition Seedling survival Shade

Approach for electrodynamic force for compensation in low voltage circuit breaker WP 630-1.2 type

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 393-396页

作者： lu Na XU L.J Miedzifiski b Automation School Beijing University of Posts and Telecommunications Beijing 100876 China Electrical Power Engineering institute Wroclaw University of Technology Wroclaw Poland

Undesirable repulsive force between contact members due to both a current path shrink near a real contact area and/or so-called pinch effect is particularly onerous for power switch applications, and results in either contact floating or bouncing which are associated with an electric arc following contact welding. this problem is of great importance for any circuit breaker especially for compact low voltage vacuum circuit breakers. to avoid contact floating at closure and during any inrush current under short circuit conditions, the electrodynamic repulsive force can be employed successfully if we use a special compensation system flexibly combined with the contact itself. However to select and design the compensation system properly, its efficiency has to be known. this paper presents an approach to obtain the electrodynamic force value depending on different shaped (rectangular, square, circle and arch) copper plates used in the compensator by using ANSYS for current values 40 kA RMS. Curve-fitting was done according to the calculating results, the optimization designing of compensation unit is based on them.

关键词： Compensation. Electrodynamic force. FEM (Finite Element Method)

A Hyper-ellipsoid Model for Metallurgical Process Modelling by Genetic Algorithm

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Journal of Materials Science & technology 1998年第6期14卷 567-568页

作者： Li, JF Li, CH Chen, NY lu, t Chinese Acad Sci Shanghai Inst Met Shanghai 200050 Peoples R China Univ SW Louisiana Lafayette LA 70504 USA

A hyper-ellipsoid model, using genetic algorithm as method of computation, has been proposed to be used in certain metallurgical processes. it is especially suitable for the modelling of the metallurgical processes wi... 详细信息

关键词： Metallurgy

Fire occurrence in relation to bamboo dominance in the Qinling Mountains of China: Evidence from phytolith and charcoal records in Holocene sediments

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Science China Earth Sciences 2015年第7期58卷 1182-1190页

作者： Courtney Marie RAYLE Scott b.FRANKLiN lu ZhiJun School of biological Sciences University of Northern Colorado Key Laboratory of Aquatic botany and Watershed Ecology the Chinese Academy of Sciences

he internal genetic clock of semelparous mast-flowering bamboo species creates gregarious regions of flowering and death, thus leading to fuel-load accumulation that potentially promotes fire（Fire-Cycle Hypothesis）. Higher abundance of bamboo could be expected to provide greater fuel loads after flowering. Here, we investigated the possible link between bamboo dominance and fire occurrence. As the main food source for the giant panda in the Qinling Mountains of China, bashania fargesii（Farges Canebrake） and Fargesia qinlingensis（Arrow bamboo） dominate lower（1000–1900 m） and higher elevations（1800–2700 m）, respectively. Four soil profiles（elevation ranging from 1240 to 2170 m） in areas of known recent bamboo flowering events（~1980） and adjacent non-flowering sites were assessed for phytoliths and charcoal. Characteristic phytoliths were chosen to describe bamboo dynamics, and charcoal particles were extracted from the soil to reconstruct fire history. Carbon 14 dating of soil charcoal samples was conducted using an accelerator mass spectrometry technique. in addition, we chose two depths（28–52 and 90–100 cm） in one bashania profile（b. fargesii forest） and one Fargesia profile（F. qinlingensis forest） for phytolith dating. Our findings indicate that bamboo has been a dominant component of these ecosystems almost for the entire profile; some 6400 yrs for bashania and ca. 10000 yrs for the Fargesia. it is also clear from the charcoal and phytolith data that bamboo abundance and recent mast flowering were significantly related to fire occurrence for lower elevation bashania while the higher elevation Fargesia was not. One of the four profiles had chronological charcoal records throughout and the oldest charcoal aged was ~1410 yr bP, suggesting an anthropogenic origin. the mixing of phytolith and charcoal made it unrealistic to describe temporal dynamics of bamboo and fire events, and thus our interpretation is cognizant of the dating discrepancies and conservative（less-sp

关键词： bamboo dynamics bashania Fargesia fire cycle hypothesis phytolith Qinling Mountains

thermoluminescence Response of Germanium-Doped Optical Fibers to X-Ray irradiation

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Chinese Physics Letters 2012年第7期29卷 284-286页

作者： M.A.Saeed N.A.Fauzia i.Hossain A.t.Ramli b.A.tahir Department of Physics Universiti Teknologi MalaysiaSkudai-81310JohorMalaysia Department of Physics College of Sciences and ArtsKing Abdulaziz UniversityRabigh 21911P.O.Box No.344KSA

We present the characteristics of the thermoluminescence (tL) response of Ge-doped optical fibers with various energies and exposures of photon *** investigate the Ge-doped SiO2 as an efficient tL material,the tL responses are compared with commercially available standard tLD100 *** Ge-doped optical fiber and tLD100 are placed in gelatin capsules and irradiated with x-ray using a toshiba model KXO-15R x-ray *** Ge-doped fiber and tLD-100 show linear response as a function of current and time using x-ray photon of energy 60,80 and *** irradiated with 60,80 and l00kV x-ray energy at various currents (mA ),tube distance (cm) and exposure time (second) ranges,tLD100 media provide a tL yield up to two times that of Ge-doped *** energy response of the Ge-doped fibers is linear and similar over the 60-l00 kVenergy range,and its sensitivity is 0.39±0.05 of the tLD100 *** glow curves of tLD 100 and doped optical fiber are also compared.

关键词： fiber fibers photon

Structural,electronic,optical,and magnetic properties of Co-doped Cu2O

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Chinese Physics b 2017年第2期26卷 387-391页

作者： i Djabri t Rezkallah F Chemam Laboratoire de la Physique Appliquee et theorique Departement des Sciences de la matiere Universite Laarbi tebessi tebessa Algeri

We investigate the magnetic properties of Co-doped Cu_2O. We studied first the electronic and structural properties of Cu_2O using the optimization of the lattice constant which is 4.18 . the calculated gap is found between 0.825 eV and1.5 eV, these values are in good agreement with the experimental results. the Co atoms are inserted in Cu_2O by means of the density functional theory（DFt） using LSDA, LSDA ＋U, and LSDA ＋ MbJ approximations in the WiEN2 k code, based on the supercell model by setting up 12, 24, and 48 atoms in（1×1 × 2）,（1 × 2 × 2）, and（2 × 2×2） supercells respectively with one or two copper atoms being replaced by cobalt atoms. the energy difference between the ferromagnetic and antiferromagnetic coupling of the spins located on the substitute Co has been calculated in order to obtain better insight into the magnetic exchange coupling for this particular compound. the studied compound exhibits stable integer magnetic moments of 2 μband 4 μbwhen it is doped with 2 atoms of Co. Optical properties have also been worked out. the results obtained in this study demonstrate the importance of the magnetic effect in Cu_2O.

关键词： Cu2O electronic structure magnetic properties optical properties

A dissolution-diffusion sliding model for soft rock grains with hydro-mechanical effect

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第3期10卷 457-467页

作者： Z.Liu C.Y.Zhou b.t.Li Y.Q.lu X.Yang Guangdong Engineering Research Center for Major infrastructure Safety School of Civil Engineering Sun Yat-sen University

the deformation and failure of soft rock affected by hydro-mechanical（HM） effect are one of the most concerns in geotechnical engineering, which are basically attributed to the grain sliding of soft rock. this study tried to develop a dissolution-diffusion sliding model for the typical red bed soft rock in South China. based on hydration film, mineral dissolution and diffusion theory, and geochemical thermodynamics, a dissolution-diffusion sliding model with the HM effect was established to account for the sliding rate. Combined with the digital image processing technology, the relationship between the grain size of soft rock and the amplitude of sliding surface was presented. An equation for the strain rate of soft rocks under steady state was also derived. the reliability of the dissolution-diffusion sliding model was verified by triaxial creep tests on the soft rock with the HM coupling effect and by the relationship between the inversion average disjoining pressure and the average thickness of the hydration film. the results showed that the sliding rate of the soft rock grains was affected significantly by the waviness of sliding surface, the shear stress, and the average thickness of hydration film. the average grain size is essential for controlling the steady-state creep rate of soft rock. this study provides a new idea for investigating the deformation and failure of soft rock with the HM effect.

关键词： Soft rock Hydro-mechanical (HM) effect Mineral dissolution-diffusion Grain sliding model

Acquired coarctation of abdominal aorta by hydatid disease

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Hepatobiliary Surgery and Nutrition 2021年第5期10卷 744-745页

作者： i-Chin Lee Qian lu Hepato-Pancreato-biliary Center Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijingChina

A 45-year-old woman presented to the hospital with severe back pain,inability to stand,and increased blood pressure for 4 *** had been diagnosed with hepatic hydatid disease 4 years ago but refused any *** examination revealed an upper limb blood pressure of 199/104 mmHg,compared to the lower limb’s 113/80 *** scans discovered a large hilar mass involved in the abdominal aorta(Panel 1A),pathologic fractures of the t12-L2 vertebras(Panel 1b),and the coarctation of abdominal aorta at the L1 vertebra level(Panel 1C).the patient was treated with Urapidil and Nifedipine for hypertension and Albendazole for hydatid *** the blood pressure was controlled at 150/100 mmHg,the patient underwent laminectomy and *** examination confirmed alveolar echinococcosis(AE).the patient was able to walk 3 months after the surgery but died 1 year after the presentation due to disease progression.

关键词： hydatid abdominal hepatic

On the founder effect in COViD-19 outbreaks:how many infected travelers may have started them all?

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National Science Review 2021年第1期8卷 30-39页

作者： Yongsen Ruan Zhida luo Xiaolu tang Guanghao Li Haijun Wen Xionglei He Xuemei lu Jian lu Chung-i Wu State Key Laboratory of biocontrol School of Life Sciences Sun Yat-sen University State Key Laboratory of Protein and Plant Gene Research Center for Bioinformatics School of Life SciencesPeking University CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of Genomics Chinese Academy of Sciences State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyCenter for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

How many incoming travelers（i;at time 0, equivalent to the ‘founders’ in evolutionary genetics） infected with SARS-CoV-2 who visit or return to a region could have started the epidemic of that region? i;would be informative about the initiation and progression of epidemics. to obtain i;, we analyze the genetic divergence among viral populations of different regions. by applying the ‘individual-output’ model of genetic drift to the SARS-CoV-2 diversities, we obtain i;ich could have been achieved by one infected traveler in a long-distance flight. the conclusion is robust regardless of the source population, the continuation of inputs（i;for t > 0） or the fitness of the variants. With such a tiny trickle of human movement igniting many outbreaks, the crucial stage of repressing an epidemic in any region should,therefore, be the very first sign of local contagion when positive cases first become identifiable. the implications of the highly ‘portable’ epidemics, including their early evolution prior to any outbreak, are explored in the companion study（Ruan et al., personal communication）.

关键词： SARS-CoV-2 COViD-19 population genetics genetic drift founder effect