Objectives: Vitamin E is an important human lipophilic antioxidant and is required for many metabolic functions. A high vitamin E intake appears to favorably impact a variety of disease processes. The vitamin E intake...Objectives: Vitamin E is an important human lipophilic antioxidant and is required for many metabolic functions. A high vitamin E intake appears to favorably impact a variety of disease processes. The vitamin E intake, excluding sup-plemental intake, of the vast majority of adults is below the current recommended level. By consuming vitamin E-enriched food, it is possible to take in adequate amounts of vitamin E. Vitamin E intake from enriched foods might prevent certain diseases without the need to ingest specific vitamin E supplements. The vitamin E that is present in enriched foods has to exhibit maximal bioavailability to ensure a sufficient intake of vitamin E from one portion of fortified food. The aim of the present study was to develop an enriched food that has highly bioavailable vitamin E. Furthermore, we wanted to examine whether vitamin E bioavailability can be affected by the technological properties of fortified food. Methods: Volunteers were given test foods (cream cheese and mayonnaise) that had been fortified with 60 mg of RRR-α-tocopherol. The test foods were technologically modified and the bioavailability of RRR-α-tocopherol was determined via a short-term kinetic measurement, which was 24 h long, and a long-term kinetic measurement, which was 28 d long. The test foods were characterized with respect to matrix properties. Results: In comparison to the mayonnaise group the serum α-tocopherol area under the curve (AUC) was significantly higher in the cream cheese group, as shown in the short-term kinetic (p = 0.010) and long-term kinetic (p = 0.017) studies. Conclusions: In conclusion, RRR-α-tocopherol was more bioavailable in cream cheese than in mayonnaise in both short-term and long-term periods. Hence, food matrices affect bioavailability of RRR-α-tocopherol. Fortified foods with proven high α-tocopherol bioavailabilities could be merchandised as functional foods with diseases prevention properties.展开更多
The recent completion of the rose genome sequence is not the end of a process,but rather a starting point that opens up a whole set of new and exciting activities.Next to a high-quality genome sequence other genomic t...The recent completion of the rose genome sequence is not the end of a process,but rather a starting point that opens up a whole set of new and exciting activities.Next to a high-quality genome sequence other genomic tools have also become available for rose,including transcriptomics data,a high-density single-nucleotide polymorphism array and software to perform linkage and quantitative trait locus mapping in polyploids.Rose cultivars are highly heterogeneous and diverse.This vast diversity in cultivated roses can be explained through the genetic potential of the genus,introgressions from wild species into commercial tetraploid germplasm and the inimitable efforts of historical breeders.We can now investigate how this diversity can best be exploited and refined in future breeding work,given the rich molecular toolbox now available to the rose breeding community.This paper presents possible lines of research now that rose has entered the genomics era,and attempts to partially answer the question that arises after the completion of any draft genome sequence:‘Now that we have“the”genome,what’s next?’.Having access to a genome sequence will allow both(fundamental)scientific and(applied)breeding-orientated questions to be addressed.We outline possible approaches for a number of these questions.展开更多
Low frequency oscillations of temperature field in the industrial induction channel furnace(ICF)with symmetrical and widened channel branches as well as different iron yoke positions are obtained using Large Eddy Simu...Low frequency oscillations of temperature field in the industrial induction channel furnace(ICF)with symmetrical and widened channel branches as well as different iron yoke positions are obtained using Large Eddy Simulation(LES)approach.The application of k-ω Shear Stress Transport(SST)turbulence model for computations of ICF with typical clogging shapes shows their influence on temperature and induced Joule heat power distributions,which are to be precise in LES study.展开更多
It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essent...It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV).展开更多
Prof.Zhanguo Wang,a world-famous semiconductor materials physicist,was born on December 29,1938,in Zhenping County,Henan Province,China.After graduating from the Department of Physics,Nankai University in 1962,he join...Prof.Zhanguo Wang,a world-famous semiconductor materials physicist,was born on December 29,1938,in Zhenping County,Henan Province,China.After graduating from the Department of Physics,Nankai University in 1962,he joined the Institute of Semiconductors,Chinese Academy of Sciences,until now.Prof.Wang has made outstanding achievements in the field of semiconductor materials and material physics.He has engaged in the study of the irradiation effect of silicon solar cells used in artificial satellites and the devices/modules in nuclear transient irradiation in his early career,which significantly contributed to the realization of atomic/hydrogen bombs and artificial satellites in China.Prof.Wang joined the Department of Solid State Physics,the University of Lund,from 1980 to 1983,where he worked on deep energy level physics and photoluminescence studies of semiconductors.He and collaborators developed a new method to identify whether the two-deep levels within a bandgap are coupled,thus solving the longexisting argument for the nature of gold-related donors and acceptors in silicon and A and B deep levels in liquid phase epitaxy grown GaAs.展开更多
Desert rhizoliths are generally found as weathered,broken and scattered samples on dune field surface,but rarely insitu in their initial states buried under the soil of desert in the Badain Jaran Desert,northwest Chin...Desert rhizoliths are generally found as weathered,broken and scattered samples on dune field surface,but rarely insitu in their initial states buried under the soil of desert in the Badain Jaran Desert,northwest China.This study off ers an assessment of the morphological,mineralogical,and chemical properties of intact and in-situ rhizoliths found in soils of swales and depressions among dune chains.The characteristics of these rare and precious objects were assessed using optical polarizing microscopy,cathodoluminescence,scanning electronic microscopy,radiocarbon dating,and stable isotopic analyses,providing the opportunity for discussion of the rhizolith formation mechanisms and associated environmental conditions.Field and laboratory investigations showed that the in-situ intact rhizoliths were formed only in the places where Artemisia shrubs are living,and the remaining root relicts within rhizoliths belong to this species.The spatial distribution of rhizoliths also suggested that low topographic positions on a landscape provided soil moisture,and redox environments favored rhizolith formation.A semi-closed redox environment in the subsoil at swales and depressions,where water is always present,along with the sandy soil texture,facilitated fast water percolation to deeper depths and condensation.Such a soil environment not only provides water for Artemisia growth,but also for the weathering of minerals such as felspars and calcite from primary carbonates,and for the decomposition of root relicts.Furthermore,harsh climatic conditions,such as strong winds and solar radiation,led to water evaporation through dead root channels and triggered the calcification along the root relicts.The entrapped lithogenic carbonates and to a lesser extent the decomposition of Artemisia roots provided the carbon sources for the rhizoliths formation,while the weathering of soil minerals,particularly feldspars and carbonates,was the main source of Ca.Rhizoliths in the Badain Jaran desert formed relatively quickly,probably over a few soil drying episodes.This led to the entrapment of a large quantity of lithogenic carbonates(more than 90%of carbon)within rhizolith cement.The re-dissolution of the entrapped lithogenic carbonates in rhizolith tubes should be taken into account in the paleoenvironmental interpretation ofC ages,the latter suggesting that rhizoliths formed during the Holocene(~2053 years cal BP,based on root organic relicts).展开更多
Single photon sources are key components for quantum technologies such as quantum communication, computing and metrology. A key challenge towards the realization of global quantum networks are transmission losses in o...Single photon sources are key components for quantum technologies such as quantum communication, computing and metrology. A key challenge towards the realization of global quantum networks are transmission losses in optical fibers. Therefore, single photon sources are required to emit at the low-loss telecom wavelength bands. However, an ideal telecom wavelength single photon source has yet to be discovered. Here, we review the recent progress in realizing such sources. We start with single photon emission based on atomic ensembles and spontaneous parametric down conversion, and then focus on solid-state emitters including semiconductor quantum dots, defects in silicon carbide and carbon nanotubes. In conclusion, some state-of-the-art applications are highlighted.展开更多
Semiconductor quantum dots are leading candidates for the on-demand generation of single photons and entangled photon pairs.High photon quality and indistinguishability of photons from different sources are critical f...Semiconductor quantum dots are leading candidates for the on-demand generation of single photons and entangled photon pairs.High photon quality and indistinguishability of photons from different sources are critical for quantum information applications.The inability to grow perfectly identical quantum dots with ideal optical properties necessitates the application of post-growth tuning techniques via e.g.temperature,electric,magnetic or strain fields.In this review,we summarize the state-of-the-art and highlight the advantages of strain tunable non-classical photon sources based on epitaxial quantum dots.Using piezoelectric crystals like PMN-PT,the wavelength of single photons and entangled photon pairs emitted by InGaAs/GaAs quantum dots can be tuned reversibly.Combining with quantum light-emitting diodes simultaneously allows for electrical triggering and the tuning of wavelength or exciton fine structure.Emission from light hole exciton can be tuned,and quantum dot containing nanostructure such as nanowires have been piezo-integrated.To ensure the indistinguishability of photons from distant emitters,the wavelength drift caused by piezo creep can be compensated by frequency feedback,which is verified by two-photon interference with photons from two stabilized sources.Therefore,strain tuning proves to be a flexible and reliable tool for the development of scalable quantum dots-based non-classical photon sources.展开更多
Papyrus is increasingly suggested as an alternative bioenergy source to reduce the pressure on forest ecosystems. However, there are few studies on the economic viability of papyrus wetlands and the benefits for local...Papyrus is increasingly suggested as an alternative bioenergy source to reduce the pressure on forest ecosystems. However, there are few studies on the economic viability of papyrus wetlands and the benefits for local communities. We construct a village Computable General Equilibrium (CGE) model to examine whether papyrus harvesting and processing has the potential to improve local livelihoods and simultaneously counteract pressure on local forest resources. We apply the CGE model to a village in northern Zambia where overexploitation of forest resources to produce energy from firewood and charcoal poses a serious problem. The analysis is based on survey data?from 105 households collected in 2015. The model results show that papyrus briquetting would be a possible?alternative biofuel and that this technology improves household income and utility through?labor?reallocations. Higher opportunity costs lead to households switching from firewood extraction and charcoal production activities to papyrus harvesting and processing to produce bioenergy. Replacing energy supplies from firewood and charcoal with papyrus briquettes results in substitution effects between forest land and wetland and thereby reduces the pressure on local forest resources. The CGE approach allows for an economy-wide ex-ante analysis at village level and can support management decisions to ensure the success of papyrus bioenergy interventions.展开更多
We present a cohesive zone model for delamination in thin shells and composite structures.The isogeometric(IGA)thin shell model is based on Kirchhoff-Love theory.Non-Uniform Rational B-Splines(NURBS)are used to discre...We present a cohesive zone model for delamination in thin shells and composite structures.The isogeometric(IGA)thin shell model is based on Kirchhoff-Love theory.Non-Uniform Rational B-Splines(NURBS)are used to discretize the exact mid-surface of the shell geometry exploiting their C 1-continuity property which avoids rotational degrees of freedom.The fracture process zone is modeled by interface elements with a cohesive law.Two numerical examples are presented to test and validate the proposed formulation in predicting the delamination behavior of composite structures.展开更多
The heat transfer perfonmance of a vertical two-phase closed thermosyphon(TPCT)used in a geothermal heat pump was experimentally investigated.The TPCT is a verticalplain steel pipe with inner diameter of 114 mm and bo...The heat transfer perfonmance of a vertical two-phase closed thermosyphon(TPCT)used in a geothermal heat pump was experimentally investigated.The TPCT is a verticalplain steel pipe with inner diameter of 114 mm and bored 368 m deep underground.Carbon dioxide(CO_(2))is used as working fluid.In the TPCT there is no condensation section.CO_(2)is condensed by the evaporator pf the heat pump,flows into the head of the TPCT and nuns down as a falling film along the inner wall of the pipe.For the heat transfer simulation in the TPCT,a quasi-dynamic model in which the mass transfer between the liquid and vapor phases as well as the conduction heat transfer from the surrounding soil towards the pipe is treated dynamically.However the film flow modeling is based on the Nusselt theory of frilm condenssation.The compauison of the experimental data with the numerical simulation is presented and discussed.展开更多
Automation of production in the nurseries of flower producing companies using barcode scanners have been attempted but with little success.Stationary laser barcode scanners which have been used for automation have fai...Automation of production in the nurseries of flower producing companies using barcode scanners have been attempted but with little success.Stationary laser barcode scanners which have been used for automation have failed due to the close proximity between the barcode and the scanner,and factors such as speed,angle of inclination of the barcode,damage to the barcode and dirt on the barcode.Furthermore,laser barcode scanners are still being used manually in the nurseries making work laborious and time consuming,which leading to reduced productivity.Therefore,an automated image-based barcode detection system to help solve the aforementioned problems was proposed.Experiments were conducted under different situations with clean and artificially soiled Code 128 barcodes in both the laboratory and under real production conditions in a flower producing company.The images were analyzed with a specific algorithm developed with the software tool Halcon.Overall the results from the company showed that the image-based system has a future prospect for automation in the nursery.展开更多
Phosphatidylcholine-hydrolyzing phospholipase C （PC-PLC） catalyzes the hydrolysis of phosphatidylcholine （PC） to generate phosphocholine and diacylglycerol （DAG）. PC-PLC has a long tradition in animal signal tra...Phosphatidylcholine-hydrolyzing phospholipase C （PC-PLC） catalyzes the hydrolysis of phosphatidylcholine （PC） to generate phosphocholine and diacylglycerol （DAG）. PC-PLC has a long tradition in animal signal transduction to generate DAG as a second messenger besides the classical phosphatidylinositol splitting phospholipase C （PI-PLC）. Based on amino acid sequence similarity to bacterial PC-PLC, six putative PC-PLC genes （NPC1 to NPC6） were identified in the Arabidopsis genome. RT-PCR analysis revealed overlapping expression pattern of NPC genes in root, stem, leaf, flower, and silique. In auxin-treated PNPc3：GUS and PNPc4：GUS seedlings, strong increase of GUS activity was visible in roots, leaves, and shoots and, to a weaker extent, in brassinolide-treated （BL） seedlings. PNPc4：GUS seedlings also responded to cytokinin with increased GUS activity in young leaves. Compared to wild-type, T-DNA insertional knockouts npc3 and npc4 showed shorter primary roots and lower lateral root density at low BL concentrations but increased lateral root densities in response to exogenous 0.05-1.0 I^M BL BL-induced expression of TCH4 and LRX2, which are involved in cell expansion, was impaired but not impaired in repression of CPD, a BL biosynthesis gene, in BL-treated npc3 and npc4. These observations suggest NPC3 and NPC4 are important in BL-mediated signaling in root growth. When treated with 0.1 I^M BL, DAG accumulation was observed in tobacco BY-2 cell cultures labeled with fluorescent PC as early as 15 min after application. We hypothesize that at least one PC-PLC is a plant signaling enzyme in BL signal transduction and, as shown earlier, in elicitor signal transduction.展开更多
We present a deep-learning framework,CrysXPP,to allow rapid and accurate prediction of electronic,magnetic,and elastic properties of a wide range of materials.CrysXPP lowers the need for large property tagged datasets...We present a deep-learning framework,CrysXPP,to allow rapid and accurate prediction of electronic,magnetic,and elastic properties of a wide range of materials.CrysXPP lowers the need for large property tagged datasets by intelligently designing an autoencoder,CrysAE.The important structural and chemical properties captured by CrysAE from a large amount of available crystal graphs data helped in achieving low prediction errors.Moreover,we design a feature selector that helps to interpret the model’s prediction.Most notably,when given a small amount of experimental data,CrysXPP is consistently able to outperform conventional DFT.A detailed ablation study establishes the importance of different design steps.We release the large pre-trained model CrysAE.We believe by fine-tuning the model with a small amount of property-tagged data,researchers can achieve superior performance on various applications with a restricted data source.展开更多
文摘Objectives: Vitamin E is an important human lipophilic antioxidant and is required for many metabolic functions. A high vitamin E intake appears to favorably impact a variety of disease processes. The vitamin E intake, excluding sup-plemental intake, of the vast majority of adults is below the current recommended level. By consuming vitamin E-enriched food, it is possible to take in adequate amounts of vitamin E. Vitamin E intake from enriched foods might prevent certain diseases without the need to ingest specific vitamin E supplements. The vitamin E that is present in enriched foods has to exhibit maximal bioavailability to ensure a sufficient intake of vitamin E from one portion of fortified food. The aim of the present study was to develop an enriched food that has highly bioavailable vitamin E. Furthermore, we wanted to examine whether vitamin E bioavailability can be affected by the technological properties of fortified food. Methods: Volunteers were given test foods (cream cheese and mayonnaise) that had been fortified with 60 mg of RRR-α-tocopherol. The test foods were technologically modified and the bioavailability of RRR-α-tocopherol was determined via a short-term kinetic measurement, which was 24 h long, and a long-term kinetic measurement, which was 28 d long. The test foods were characterized with respect to matrix properties. Results: In comparison to the mayonnaise group the serum α-tocopherol area under the curve (AUC) was significantly higher in the cream cheese group, as shown in the short-term kinetic (p = 0.010) and long-term kinetic (p = 0.017) studies. Conclusions: In conclusion, RRR-α-tocopherol was more bioavailable in cream cheese than in mayonnaise in both short-term and long-term periods. Hence, food matrices affect bioavailability of RRR-α-tocopherol. Fortified foods with proven high α-tocopherol bioavailabilities could be merchandised as functional foods with diseases prevention properties.
基金supported in part by the TKI polyploids project‘Novel genetic and genomic tools for polyploid crops’(BO-26.03-009-004 and BO-50-002-022).
文摘The recent completion of the rose genome sequence is not the end of a process,but rather a starting point that opens up a whole set of new and exciting activities.Next to a high-quality genome sequence other genomic tools have also become available for rose,including transcriptomics data,a high-density single-nucleotide polymorphism array and software to perform linkage and quantitative trait locus mapping in polyploids.Rose cultivars are highly heterogeneous and diverse.This vast diversity in cultivated roses can be explained through the genetic potential of the genus,introgressions from wild species into commercial tetraploid germplasm and the inimitable efforts of historical breeders.We can now investigate how this diversity can best be exploited and refined in future breeding work,given the rich molecular toolbox now available to the rose breeding community.This paper presents possible lines of research now that rose has entered the genomics era,and attempts to partially answer the question that arises after the completion of any draft genome sequence:‘Now that we have“the”genome,what’s next?’.Having access to a genome sequence will allow both(fundamental)scientific and(applied)breeding-orientated questions to be addressed.We outline possible approaches for a number of these questions.
基金Item Sponsored by European Social Fund(ESF),contract No.2009/0223/1DP/1.1.1.2.0/09/APIA/VIAA/008
文摘Low frequency oscillations of temperature field in the industrial induction channel furnace(ICF)with symmetrical and widened channel branches as well as different iron yoke positions are obtained using Large Eddy Simulation(LES)approach.The application of k-ω Shear Stress Transport(SST)turbulence model for computations of ICF with typical clogging shapes shows their influence on temperature and induced Joule heat power distributions,which are to be precise in LES study.
基金Antrag GZ 398, Chinesisch-Deutsches Zentrum für Wissenschaftsfrderung,2006.
文摘It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV).
文摘Prof.Zhanguo Wang,a world-famous semiconductor materials physicist,was born on December 29,1938,in Zhenping County,Henan Province,China.After graduating from the Department of Physics,Nankai University in 1962,he joined the Institute of Semiconductors,Chinese Academy of Sciences,until now.Prof.Wang has made outstanding achievements in the field of semiconductor materials and material physics.He has engaged in the study of the irradiation effect of silicon solar cells used in artificial satellites and the devices/modules in nuclear transient irradiation in his early career,which significantly contributed to the realization of atomic/hydrogen bombs and artificial satellites in China.Prof.Wang joined the Department of Solid State Physics,the University of Lund,from 1980 to 1983,where he worked on deep energy level physics and photoluminescence studies of semiconductors.He and collaborators developed a new method to identify whether the two-deep levels within a bandgap are coupled,thus solving the longexisting argument for the nature of gold-related donors and acceptors in silicon and A and B deep levels in liquid phase epitaxy grown GaAs.
基金the Natural Science Foundation of China(41561046)Chinese-German Centre(Sino-German Mobility M-0069)the German Research Foundation(DFG)(ZA 1068/4-1)。
文摘Desert rhizoliths are generally found as weathered,broken and scattered samples on dune field surface,but rarely insitu in their initial states buried under the soil of desert in the Badain Jaran Desert,northwest China.This study off ers an assessment of the morphological,mineralogical,and chemical properties of intact and in-situ rhizoliths found in soils of swales and depressions among dune chains.The characteristics of these rare and precious objects were assessed using optical polarizing microscopy,cathodoluminescence,scanning electronic microscopy,radiocarbon dating,and stable isotopic analyses,providing the opportunity for discussion of the rhizolith formation mechanisms and associated environmental conditions.Field and laboratory investigations showed that the in-situ intact rhizoliths were formed only in the places where Artemisia shrubs are living,and the remaining root relicts within rhizoliths belong to this species.The spatial distribution of rhizoliths also suggested that low topographic positions on a landscape provided soil moisture,and redox environments favored rhizolith formation.A semi-closed redox environment in the subsoil at swales and depressions,where water is always present,along with the sandy soil texture,facilitated fast water percolation to deeper depths and condensation.Such a soil environment not only provides water for Artemisia growth,but also for the weathering of minerals such as felspars and calcite from primary carbonates,and for the decomposition of root relicts.Furthermore,harsh climatic conditions,such as strong winds and solar radiation,led to water evaporation through dead root channels and triggered the calcification along the root relicts.The entrapped lithogenic carbonates and to a lesser extent the decomposition of Artemisia roots provided the carbon sources for the rhizoliths formation,while the weathering of soil minerals,particularly feldspars and carbonates,was the main source of Ca.Rhizoliths in the Badain Jaran desert formed relatively quickly,probably over a few soil drying episodes.This led to the entrapment of a large quantity of lithogenic carbonates(more than 90%of carbon)within rhizolith cement.The re-dissolution of the entrapped lithogenic carbonates in rhizolith tubes should be taken into account in the paleoenvironmental interpretation ofC ages,the latter suggesting that rhizoliths formed during the Holocene(~2053 years cal BP,based on root organic relicts).
基金financially supported by the ERC Starting Grant No.715770(QD-NOMS)the National Natural Science Foundation of China(No.61728501)
文摘Single photon sources are key components for quantum technologies such as quantum communication, computing and metrology. A key challenge towards the realization of global quantum networks are transmission losses in optical fibers. Therefore, single photon sources are required to emit at the low-loss telecom wavelength bands. However, an ideal telecom wavelength single photon source has yet to be discovered. Here, we review the recent progress in realizing such sources. We start with single photon emission based on atomic ensembles and spontaneous parametric down conversion, and then focus on solid-state emitters including semiconductor quantum dots, defects in silicon carbide and carbon nanotubes. In conclusion, some state-of-the-art applications are highlighted.
基金financially supported by the ERC Starting Grant No.715770(QD-NOMS)the National Natural Science Foundation of China(No.61728501)
文摘Semiconductor quantum dots are leading candidates for the on-demand generation of single photons and entangled photon pairs.High photon quality and indistinguishability of photons from different sources are critical for quantum information applications.The inability to grow perfectly identical quantum dots with ideal optical properties necessitates the application of post-growth tuning techniques via e.g.temperature,electric,magnetic or strain fields.In this review,we summarize the state-of-the-art and highlight the advantages of strain tunable non-classical photon sources based on epitaxial quantum dots.Using piezoelectric crystals like PMN-PT,the wavelength of single photons and entangled photon pairs emitted by InGaAs/GaAs quantum dots can be tuned reversibly.Combining with quantum light-emitting diodes simultaneously allows for electrical triggering and the tuning of wavelength or exciton fine structure.Emission from light hole exciton can be tuned,and quantum dot containing nanostructure such as nanowires have been piezo-integrated.To ensure the indistinguishability of photons from distant emitters,the wavelength drift caused by piezo creep can be compensated by frequency feedback,which is verified by two-photon interference with photons from two stabilized sources.Therefore,strain tuning proves to be a flexible and reliable tool for the development of scalable quantum dots-based non-classical photon sources.
文摘Papyrus is increasingly suggested as an alternative bioenergy source to reduce the pressure on forest ecosystems. However, there are few studies on the economic viability of papyrus wetlands and the benefits for local communities. We construct a village Computable General Equilibrium (CGE) model to examine whether papyrus harvesting and processing has the potential to improve local livelihoods and simultaneously counteract pressure on local forest resources. We apply the CGE model to a village in northern Zambia where overexploitation of forest resources to produce energy from firewood and charcoal poses a serious problem. The analysis is based on survey data?from 105 households collected in 2015. The model results show that papyrus briquetting would be a possible?alternative biofuel and that this technology improves household income and utility through?labor?reallocations. Higher opportunity costs lead to households switching from firewood extraction and charcoal production activities to papyrus harvesting and processing to produce bioenergy. Replacing energy supplies from firewood and charcoal with papyrus briquettes results in substitution effects between forest land and wetland and thereby reduces the pressure on local forest resources. The CGE approach allows for an economy-wide ex-ante analysis at village level and can support management decisions to ensure the success of papyrus bioenergy interventions.
文摘We present a cohesive zone model for delamination in thin shells and composite structures.The isogeometric(IGA)thin shell model is based on Kirchhoff-Love theory.Non-Uniform Rational B-Splines(NURBS)are used to discretize the exact mid-surface of the shell geometry exploiting their C 1-continuity property which avoids rotational degrees of freedom.The fracture process zone is modeled by interface elements with a cohesive law.Two numerical examples are presented to test and validate the proposed formulation in predicting the delamination behavior of composite structures.
基金The present research work was supported by the Federal Ministry for Economic Affairs and Energy of Germanyunder the funding code FKZ:03ET1050B.
文摘The heat transfer perfonmance of a vertical two-phase closed thermosyphon(TPCT)used in a geothermal heat pump was experimentally investigated.The TPCT is a verticalplain steel pipe with inner diameter of 114 mm and bored 368 m deep underground.Carbon dioxide(CO_(2))is used as working fluid.In the TPCT there is no condensation section.CO_(2)is condensed by the evaporator pf the heat pump,flows into the head of the TPCT and nuns down as a falling film along the inner wall of the pipe.For the heat transfer simulation in the TPCT,a quasi-dynamic model in which the mass transfer between the liquid and vapor phases as well as the conduction heat transfer from the surrounding soil towards the pipe is treated dynamically.However the film flow modeling is based on the Nusselt theory of frilm condenssation.The compauison of the experimental data with the numerical simulation is presented and discussed.
基金This project was part of the WeGa-Network(www.wega-online.org)funded by the German Federal Ministry of Education and Research.
文摘Automation of production in the nurseries of flower producing companies using barcode scanners have been attempted but with little success.Stationary laser barcode scanners which have been used for automation have failed due to the close proximity between the barcode and the scanner,and factors such as speed,angle of inclination of the barcode,damage to the barcode and dirt on the barcode.Furthermore,laser barcode scanners are still being used manually in the nurseries making work laborious and time consuming,which leading to reduced productivity.Therefore,an automated image-based barcode detection system to help solve the aforementioned problems was proposed.Experiments were conducted under different situations with clean and artificially soiled Code 128 barcodes in both the laboratory and under real production conditions in a flower producing company.The images were analyzed with a specific algorithm developed with the software tool Halcon.Overall the results from the company showed that the image-based system has a future prospect for automation in the nursery.
文摘Phosphatidylcholine-hydrolyzing phospholipase C （PC-PLC） catalyzes the hydrolysis of phosphatidylcholine （PC） to generate phosphocholine and diacylglycerol （DAG）. PC-PLC has a long tradition in animal signal transduction to generate DAG as a second messenger besides the classical phosphatidylinositol splitting phospholipase C （PI-PLC）. Based on amino acid sequence similarity to bacterial PC-PLC, six putative PC-PLC genes （NPC1 to NPC6） were identified in the Arabidopsis genome. RT-PCR analysis revealed overlapping expression pattern of NPC genes in root, stem, leaf, flower, and silique. In auxin-treated PNPc3：GUS and PNPc4：GUS seedlings, strong increase of GUS activity was visible in roots, leaves, and shoots and, to a weaker extent, in brassinolide-treated （BL） seedlings. PNPc4：GUS seedlings also responded to cytokinin with increased GUS activity in young leaves. Compared to wild-type, T-DNA insertional knockouts npc3 and npc4 showed shorter primary roots and lower lateral root density at low BL concentrations but increased lateral root densities in response to exogenous 0.05-1.0 I^M BL BL-induced expression of TCH4 and LRX2, which are involved in cell expansion, was impaired but not impaired in repression of CPD, a BL biosynthesis gene, in BL-treated npc3 and npc4. These observations suggest NPC3 and NPC4 are important in BL-mediated signaling in root growth. When treated with 0.1 I^M BL, DAG accumulation was observed in tobacco BY-2 cell cultures labeled with fluorescent PC as early as 15 min after application. We hypothesize that at least one PC-PLC is a plant signaling enzyme in BL signal transduction and, as shown earlier, in elicitor signal transduction.
文摘We present a deep-learning framework,CrysXPP,to allow rapid and accurate prediction of electronic,magnetic,and elastic properties of a wide range of materials.CrysXPP lowers the need for large property tagged datasets by intelligently designing an autoencoder,CrysAE.The important structural and chemical properties captured by CrysAE from a large amount of available crystal graphs data helped in achieving low prediction errors.Moreover,we design a feature selector that helps to interpret the model’s prediction.Most notably,when given a small amount of experimental data,CrysXPP is consistently able to outperform conventional DFT.A detailed ablation study establishes the importance of different design steps.We release the large pre-trained model CrysAE.We believe by fine-tuning the model with a small amount of property-tagged data,researchers can achieve superior performance on various applications with a restricted data source.
