检索结果-南通市图书馆

High Responsivity and Ultra-Low Detection Limits in nonlinear a-Si:H p-i-n Photodiodes Enabled by Photogating

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonic Sensors 2023年第4期13卷 27-38页

作者： Andreas BABLICH Maurice MÜLLER Rainer BORnEMAnn Andreas nACHTIGAL Peter HARInG BOLÍvar Institute of Graphene-Based nanotechnology University of SiegenHölderlinstr.357076 SiegenGermany Institute of High Frequency and Quantum Electronics University of SiegenHölderlinstr.357076 SiegenGermany

Photodetectors operating at the wavelength in the visible spectrum are key components in high-performance optoelectronic *** this work,massive nonlinearities in amorphous silicon p-i-n photodiodes enabled by the photogating are presented,resulting in responsivities up to 744 mA/W at blue *** detectors exhibit significant responsivity gains at optical modulation frequencies exceeding MHz and a more than 60-fold enhanced spectral response compared to the non-gated *** detection limits down to 10.4 nW/mm^(2) and mean signal-to-noise ratio enhancements of 8.5dB are demonstrated by illuminating the sensor with an additional 6.6μW/mm^(2) red ***-optical simulations verify photocarrier modulation due to defect-induced field screening to be the origin of such high responsivity *** experimental results validate the theory and enable the development of commercially viable and complementary metal oxide semiconductor(CMOS)compatible high responsivity photodetectors operating in the visible range for low-light level imaging and detection.

关键词： Photogating amorphous silicon a-Si:H nonlinearity photodetector responsivity gain

nanofabricated high turn-density spiral coils for on-chip electromagneto-optical conversion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microsystems & nanoengineering 2024年第2期10卷 181-192页

作者： Ilhan Bok Alireza Ashtiani Yash gokhale Jack Phillips Tianxiang Zhu Aviad Hai Department of Biomedical Engineering University of Wisconsin–MadisonMadisonWIUSA Department of Electrical and Computer Engineering University of Wisconsin–MadisonMadisonWIUSA Wisconsin Institute for Translational neuroengineering(WITne) University of Wisconsin–MadisonMadisonWIUSA

Circuit-integrated electromagnets are fundamental building blocks for on-chip signal transduction,modulation,and tunability,with specific applications in environmental and biomedical micromagnetometry.A primary challenge for improving performance is pushing quality limitations while minimizing size and fabrication complexity and retaining spatial *** efforts have exploited highly involved three-dimensional synthesis,advanced insulation,and exotic material ***,we present a rapid nanofabrication process that employs electron beam dose control for high-turn-density diamond-embedded flat spiral coils;these coils achieve efficient on-chip electromagnetic-to-optical signal *** fabrication process relies on fast 12.3 s direct writing on standard poly(methyl methacrylate)as a basis for the metal lift-off *** with 70 micrometer overall diameters and 49–470 nm interturn spacings with corresponding inductances of 12.3–12.8 nH are *** utilize optical micromagnetometry to demonstrate that magnetic field generation at the center of the structure effectively correlates with finite element modeling *** designs based on our process can be integrated with photolithography to broadly enable optical magnetic sensing and spin-based computation.

关键词： utilize retaining high

Diversity and regeneration status of Sarkot Van Panchyat in Garhwal Himalaya, India

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2012年第3期23卷 399-404页

作者： nazir A.Pala A.K.negi Yogesh gokhale Jahangeer A.Bhat n.P.Todaria Department of Forestry and natural Resources Chauras Campus HnB Garhwal University Srinagar Garhwal Uttarakhand P.Box-59India The Energy and Resources Institute(TERI)new Delhi-Darbari SethBlock Habitat Place Lodhi RoadNew Delhi-110003India

We investigated the floristic composition, phytosociological and regeneration status of Sarkot Van Panchyat （community forest） in Chamoli district of Garhwal Himalaya. A total of 52 plant species of 46 genera and 26 families were recorded, which included 12 trees, 18 shrubs and 22 herb species. Quercus leucotrichophora was dominant tree species in sapling and seedling layers, followed by Lyonia ovalifolia and Rhododendron arboreum. Out of 12 tree species, 7 species in seedling stage and 8 species in sapling stage were recorded in the study area. The 44.41% species in the study area showed good regeneration status, 16.66% species were fairly regenerating, and 8.33% species showed poor regeneration status, while 33% species were not regenerating. number of individuals from lower girth classes （0--10 cm and 10-30 cm） showed decreasing trend with the increase in size of girth class. Shannon index （H） for trees, shrubs and herbs was recorded as 1.82, 2.24 and 2.41 respectively. Simpsons index （Co） was recorded as 0.21, 0.12 and 0.12 for trees, shrubs and herbs respectively. The forest should be di- vided into compartments for better management purpose and each compartment should be closed for five years to assist regeneration and enrichment planting may also be carried out for sustainable management.

关键词： traditional forests regeneration dominant Garhwal Himalaya composition

Carbon stock estimation for tree species of Sem Mukhem sacred forest in Garhwal Himalaya, India

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2013年第3期24卷 457-460页

作者： nazir A. Pala A. K. negi Yogesh gokhale Showkat Aziem K. K. Vikrant n. P. Todaria Department of Forestry Dolphin (PG) Institute of Biomedical and Natural SciencesManduwala Dehradun -248007 Uttarakhand India Department of Forestry and natural Resources P.O. Box-59 Chauras Campus HNB Garhwal University Srinagar GarhwalUttarkhand-246174 India The Energy and Resources Institute (TERI) New Delhi 110003 India Plant physiology division Botany discipline FRI Dehradun248006 India

Carbon stock estimation was conducted in tree species of Sem Mukhem sacred forest in district Tehri of Garhwal Himalaya, Uttara- khand, India. This forest is dedicated to nagraj Devta and is dominated by tree species, including Quercus floribunda, Quercus semecarpifolia and Rhododendron arboreum. The highest values of below ground bio- mass density, total biomass density and total carbon density were （34.81±1.68） Mg·ha^-1, （168.26±9.04） Mg·ha^-1 and （84.13±4.18） Mg·ha^-1 for Pinus wallichiana. Overall values of total biomass density and total carbon density calculated were 1549.704 Mg·ha^-1 and 774.77 Mg·ha^-1 respectively. Total value of growing stock volume density for all species was 732.56 m3·ha^-1 and ranged from （144.97±11.98） m3·ha^-1 for Pinus wallichiana to （7.78±1.78） m3·ha^-1for Benthamidia capitata.

关键词： carbon management sacred forest biomass density

Equivalent circuit for the characterization of the resonance mode in piezoelectric systems

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Dielectrics 2015年第4期5卷 37-41页

作者： Y.Fernández-Afonso O.García-Zaldívar F.Calderón-Piñar Centrode Estudios Avanzadosde Cuba Kilómetro 1y 1/2 Carreter a San Antonio de los Baños Valle Grande La LisaHabanaCuba Facultadde Física-Instituto de Cienciay Tecnología de Materiales Universidad de La Habana.San LázaroyL Vedado.La Habana 10400 Cuba CInVESTAV-Unidad Querétaro Libramiento norponiente no.2000 Realde Juriquilla QuerétaroQro.76230México

The impedance properties in polarized piezoelectric can be described by electric equivalent *** classic circuit used in the literature to describe real systems is formed by one resistor(R),one inductance(L)and one capacitance C connected in series and one capacity(C_(0))connected in parallel with the ***,the equation that describe the resonance and anti-resonance frequencies depends on a complex manner of R,L,C and C_(0).In this work is proposed a simpler model formed by one inductance(L)and one capacity(C)in series;one capacity(C_(0))in parallel;one resistor(R_(p))in parallel and one resistor(Rs)in series with other *** the traditional circuit,the equivalent circuit elements in the proposed model can be simply determined by knowing the experimental values of the resonance frequency fr,anti-resonance frequency fa,impedance module at resonance frequency|Z|,impedance module at anti-resonance frequency|Za|and low frequency capacitance C_(0),without ftting the im-pedance experimental data to the obtained equation.

关键词： Piezoelectric equivalent circuit electromechanic

Portal hypertensive biliopathy: A single center experience and literature review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Hepatology 2013年第3期5卷 137-144页

作者： Vanessa Suárez Andrés Puerta Luisa Fernanda Santos Juan Manuel Pérez Adriana var.n Rafael Claudino Botero Gastroenterology and Hepatology Service Department of Internal Medicine Fundación Cardioinfantil Department of Diagnostic Imaging Fundación Cardioinfantil

Portal hypertensive biliopathy (PHB) is characterized by anatomical and functional abnormalities of the intrahepatic, extrahepatic and pancreatic ducts, in patients with portal hypertension associated to extrahepatic portal vein obstruction and less frequently to cirrhosis. These morphological changes, consisting in dilatation and stenosis of the biliary tree, are due to extensive venous collaterals occurring in an attempt to decompress the portal venous blockage. It is usually asymptomatic until it progresses to more advanced stages with cholestasis, jaundice, biliary sludge, gallstones, cholangitis and finally biliary cirrhosis. Imaging mo-dalities of the biliary tree such as Doppler ultrasound, computed tomography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography are essential to establish the diagnosis and the need of therapeutical interventions. Once the diagnosis is established, treatment with ursodesoxycholic acid seems to be beneficial. Decompression of the biliary tree to dilate, remove stones or implant biliary prosthesis by endoscopic or surgical procedures (hepato-yeyunostomy) usually resolves the cholestatic picture and prevents septic complications. The ideal treatment is the decompression of the portal system, with transjugular intrahepatic porto-systemic shunt or a surgical porto-systemic shunt. Unfortunately, few patients will be candidates for these procedures due to the extension of the thrombotic process. The purpose of this paper is to report the first 3 cases of PHB seen in a Colombian center and to review the literature.

关键词： Bile duct diseases Biliary obstruction Banti’s syndrome Cholestasis in children Portal vein obstruction Interventional endoscopy

Tomato and Romerito Edible and Important Plants for Human Health

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Science and Engineering(B) 2022年第6期11卷 267-271页

作者： Edmundo Arias Torres Bolívar Arias Olguín Department of Applied Technology Mexican Institute of Appropriate TechnologiesS.C.Mexico CityCode.07270.México

Two plant foods are presented,Romerito and tomato,with nutritional properties that can help improve people’s *** can be grown in the open field,in a greenhouse or in a pot all year *** Romerito grows in semi-arid *** the Romerito and the tomato contain vitamins,minerals and fiber which make them complete *** can be used in cosmetology as well.

关键词： Romerito tomato vegetable food

Avocado and Chayote-Two Edible and Medicinal Plants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Science and Engineering(B) 2023年第2期12卷 70-74页

作者： Edmundo Arias Torres Bolívar Arias Olguín Department of Applied Technology Mexican Institute of Appropriate TechnologiesS.C.Mexico CityCode.07270México

There are two agricultural products originating in Mexico with nutritional,medicinal and cosmetic *** is the Avocado,the fruit of a tree that is widely accepted in the Mexican diet due to its pleasant *** other is the Chayote,a green vegetable that grows like a vine,with guides that can exceed up to 6 m in *** two foods,in addition to being consumed nationally,are also exported,which is why they are of economic importance for *** is the most exported,after coffee and tomato,with Chayote in fourth place.

关键词： Avocado chayote food.

Sustainable Development Project for a Suburban Community Located in Xalapa, Veracruz, Mexico

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Science and Engineering(A) 2020年第2期9卷 72-76页

作者： Edmundo Arias Torres Bolívar MArias Olguín Mexican Institute of Appropriate Technology(IMETA) Mexico City 07279Mexico

Rural-urban development project in an ejidal community (portion of common land several owners) is located in the suburban area of Xalapa, Veracruz, *** place where the community is located has a lagoon that was contaminated with water lily. now we want to implement a suburban sustainable development project using ecological and appropriate technologies to the community and the place, taking advantage of that body of water to grow fish and as a recreational area for visitors and thus generating food and economic resources in favor of the community with the food sales, boat rentals and recreational *** project adds to the achievement of 12 of the 17 Sustainable Development Goals of the United nations Organization.

关键词： Sustainable ecosystems appropriate technologies suburban cooperative community empowerment