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1.
Environ Sci Technol ; 58(24): 10515-10523, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38622088

RESUMEN

Hydrogen sulfide (H2S), a toxic gas abundant in natural gas fields and refineries, is currently being removed mainly via the Claus process. However, the emission of sulfur-containing pollutants is hard to be prevented and the hydrogen element is combined to water. Herein, we report an electron-mediated off-field electrocatalysis approach (OFEC) for complete splitting of H2S into H2 and S under ambient conditions. Fe(III)/Fe(II) and V(II)/V(III) redox mediators are used to fulfill the cycles for H2S oxidation and H2 production, respectively. Fe(III) effectively removes H2S with almost 100% conversion during its oxidation process. The H+ ions are reduced by V(II) on a nonprecious metal catalyst, tungsten carbide. The mediators are regenerated in an electrolyzer at a cell voltage of 1.05 V, close to the theoretical potential difference (1.02 V) between Fe(III)/Fe(II) and V(II)/V(III). In a laboratory bench-scale plant, the energy consumption for the production of H2 from H2S is estimated to be 2.8 kWh Nm-3 H2 using Fe(III)/Fe(II) and V(II)/V(III) mediators and further reduced to about 0.5 kWh Nm-3 H2 when employing well-designed heteropolyacid/quinone mediators. OFEC presents a cost-effective approach for the simultaneous production of H2 and elemental sulfur from H2S, along with the complete removal of H2S from industrial processes. It also provides a practical platform for electrochemical reactions involving solid precipitation and organic synthesis.


Asunto(s)
Sulfuro de Hidrógeno , Hidrógeno , Azufre , Sulfuro de Hidrógeno/química , Hidrógeno/química , Catálisis , Azufre/química , Oxidación-Reducción , Electroquímica , Técnicas Electroquímicas
2.
Biodegradation ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619793

RESUMEN

In order to explore the operation performance, kinetic characteristics and bacterial community of the short-cut nitrification and denitrification (SND) system, the SND system with pre-cultured short cut nitrification and denitrification sludge was established and operated under different ferrous ion (Fe (II)) conditions. Experimental results showed that the average NH4+-N removal efficiency (ARE) of SND system was 97.3% on Day 5 and maintained a high level of 94.9% ± 1.3% for a long operation period. When the influent Fe(II) concentration increased from 2.3 to 7.3 mg L-1, the sedimentation performance, sludge concentration and organic matter removal performance were improved. However, higher Fe(II) of 12.3 mg L-1 decreased the removal of nitrogen and CODCr with the relative abundance (RA) of Proteobacteria and Bacteroidetes decreased to 30.28% and 19.41%, respectively. Proteobacteria, Bacteroidetes and Firmicutes were the dominant phyla in SND system. Higher Fe(II) level of 12.3 mg L-1 increase the RA of denitrifying genus Trichococcus (33.93%), and the denitrifying genus Thauera and Tolumonas dominant at Fe(II) level of no more than 7.3 mg L-1.

3.
Plant Physiol ; 190(1): 592-604, 2022 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-35642904

RESUMEN

In ripening grape (Vitis sp.) berries, the combination of rapid sugar import, apoplastic phloem unloading, and water discharge via the xylem creates a potential risk for apoplastic sugar to be lost from the berries. We investigated the likelihood of such sugar loss and a possible sugar retrieval mechanism in the pedicels of different Vitis genotypes. Infusion of D-glucose-1-13C or L-glucose-1-13C to the stylar end of attached berries demonstrated that both sugars can be leached from the berries, but only the nontransport sugar L-glucose moved beyond the pedicels. No 13C enrichment was found in peduncles and leaves. Genes encoding 10 sugar transporters were expressed in the pedicels throughout grape ripening. Using an immunofluorescence technique, we localized the sucrose transporter SUC27 to pedicel xylem parenchyma cells. These results indicate that pedicels possess the molecular machinery for sugar retrieval from the apoplast. Plasmodesmata were observed between vascular parenchyma cells in pedicels, and movement of the symplastically mobile dye carboxyfluorescein demonstrated that the symplastic connection is physiologically functional. Taken together, the chemical, molecular, and anatomical evidence gathered here supports the idea that some apoplastic sugar can be leached from grape berries and is effectively retrieved in a two-step process in the pedicels. First, sugar transporters may actively retrieve leached sugar from the xylem. Second, retrieved sugar may move symplastically to the pedicel parenchyma for local use or storage, or to the phloem for recycling back to the berry.


Asunto(s)
Vitis , Carbohidratos/farmacología , Frutas/fisiología , Glucosa/farmacología , Azúcares/farmacología , Vitis/fisiología
4.
Planta ; 250(4): 1293-1305, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31254101

RESUMEN

MAIN CONCLUSION: Applying principles of shell theory, we found that grape berries rapidly change their behavior from thick-walled spheres to pressurized thin-walled spheres and become susceptible to splitting during berry softening. Knowledge of the rheological properties of the skin of berry fruits is needed to make decisions concerning berry splitting prevention. However, how these properties and splitting resistance respond to varietal differences and developmental changes is poorly understood. In a customized injection test, pressurized water was injected into the berries of four grape varieties until they split. In a compression test, the deformation of berries in response to berry softening or dehydration was measured. Shell theory was applied to estimate how the internal pressure translates to tensile stress on the skin. The results suggested that berry softening at the onset of ripening drastically alters berry rheological properties; berries rapidly changed from brittle to ductile materials. The skin became the major stress-bearing structure during berry softening and became vulnerable to tensile stress, which was associated with a rapid decline in splitting resistance. The rate of decline and the absolute extent of the skin's ability to bear stress varied by variety. Dehydration of overripe or water-stressed berries did not alter the skin properties but reduced the risk of berry splitting. These results indicate that the vulnerability to berry splitting is closely related to developmentally regulated changes in fruit rheological properties and water relations.


Asunto(s)
Frutas/fisiología , Vitis/fisiología , Deshidratación , Frutas/crecimiento & desarrollo , Reología , Vitis/crecimiento & desarrollo , Agua/fisiología
5.
Zhong Yao Cai ; 39(4): 764-6, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30132315

RESUMEN

Objective: To compare the arecoline content of Areca catechu seeds processed by traditional slice method and fresh-cut method,in order to provide scientific basis for processing method of Areca catechu seeds. Methods: The arecoline content was analyzed by using HPLC method. Results: The arecoline content of Areca catechu seeds by fresh-cut method was 1. 88 times of that by traditional slice method. As the betel nut is hard, compact and thus not easy to be soaked in water, it was traditionally softened by means of the combination of water immersion and pouring methods, which took too much time. Also, the effective constituent of Areca catechu seeds was soluble in water. Consequently, the traditional method of softening usually resulted in the loss of the effective constituent and even the decay of the betel nut, lowering the quality of the decoction pieces. In brief, the traditional method wasted water, manpower and resource, with low efficiency and high cost. Conclusion: Therefore, it is suggested that Areca catechu seeds should be cut into slices when fresh.


Asunto(s)
Areca , Arecolina , Cromatografía Líquida de Alta Presión , Semillas
6.
J Formos Med Assoc ; 113(11): 839-49, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25294100

RESUMEN

BACKGROUND/PURPOSE: The disability eligibility determination system is based on the International Classification of Functioning, Disability and Health (ICF) framework in Taiwan. The Functioning Disability Evaluation Scale (FUNDES) has been developed since 2007 for assessing the status of an individual's activities and participation in the disability eligibility system. The purpose of this study was to examine the reliability and validity of the FUNDES-Adult Version (FUNDES-Adult). METHODS: During 2011-2012, a total of 5736 adults with disabilities (aged 58.4 ± 18.2 years) were randomly recruited for a national population-based study. These adults were assessed in person by certified professionals in the authorized hospitals. Domains 1-6 of the FUNDES-Adult addressing the performance and capability dimensions are modified from the World Health Organization Disability Assessment Schedule 2.0-36-item version, and Domain 7 (Environmental attribute) and capability and capacity dimensions of Domain 8 (Motor action) are designed based on the ICF coding system. RESULTS: The internal consistency was excellent (Cronbach's α ≥ 0.9). An exploratory factor analysis yielded a five-factor FUNDES structure with a variance of 76.1% and 76.9% and factor loadings of 0.56-0.94 and 0.55-0.94 for the performance and capability dimensions, respectively. The factor loadings for the second-order confirmatory factor analysis for the performance and capability dimensions were from 0.81 to 0.89. In Domains 1-6 and 8, the ceiling effects were from 9% to 36%, and the floor effects were from 5% to 45%. CONCLUSION: FUNDES-Adult has acceptable reliability and validity and can be used to measure activities and participation for people with disabilities.


Asunto(s)
Evaluación de la Discapacidad , Personas con Discapacidad/clasificación , Clasificación Internacional del Funcionamiento, de la Discapacidad y de la Salud/normas , Actividades Cotidianas , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Participación Social , Taiwán , Organización Mundial de la Salud
7.
Chemosphere ; 362: 142585, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38866333

RESUMEN

Manufacturing processes in semiconductor and photonics industries involve the use of a significant amount of organic solvents. Recycle and reuse of these solvents produce distillate residues and require treatment before being discharged. This study aimed to evaluate the performance of the biological treatment system in a full-scale wastewater treatment plant that treats wastewater containing distillate residues from the recycling of electronic chemicals. Batch experiments were conducted to investigate the optimal operational conditions for the full-scale wastewater treatment plant. To achieve good nitrogen removal efficiency with effluent ammonia and nitrate concentrations below 20 mg N/L and 50 mg N/L, respectively, it was suggested to control the ammonia concentration and pH of the influent below 500 mg N/L and 8.0, respectively. In addition, the biodegradability of N-methylpyrrolidone, diethylene glycol monobutyl ether, and cyclopentanone distillate residues from the electronic chemicals manufacturing process were evaluated under aerobic, anoxic, and anaerobic conditions. N-methylpyrrolidone and cyclopentanone distillate residues were suggested to be treated under anoxic condition. However, substrate inhibition occurred when using cyclopentanone distillate residue as a carbon source with chemical oxygen demand (COD) levels higher than 866 mg/L and nitrate levels higher than 415 mg N/L. Under aerobic condition, the COD from both N-methylpyrrolidone and cyclopentanone distillate residues could be easily degraded. Nevertheless, a negative effect on nitrification was observed, with a prolonged lag time for ammonia oxidation as the initial COD concentration increased. The specific ammonia oxidation rate and nitrate production rate decreased under high COD concentration contributed by N-methylpyrrolidone and cyclopentanone distillate residues. Furthermore, the biodegradability of diethylene glycol monobutyl ether distillate residue was found to be low under aerobic, anoxic, and anaerobic conditions. With respect to the abundance of nitrogen removal microorganisms in the wastewater treatment plant, results showed that Comammox may have an advantage over ammonia oxidizing bacteria under high pH conditions. In addition, Comammox may have higher resistance to environmental changes. Dominance of Comammox over ammonia oxidizing bacteria under high ammonia condition was first reported in this study.

8.
Dev Biol ; 357(2): 541-57, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21756893

RESUMEN

An evolutionarily conserved subcircuit (kernel) dedicated to a specific developmental function is found at the top of the gene regulatory networks (GRNs) hierarchy. Here we comprehensively demonstrate that a pan-deuterostome endoderm specification kernel exists in zebrafish. We analyzed interactions among gata5, gata6, otx2 and prdm1a using specific morpholino knockdowns and measured the gene expression profiles by quantitative real-time RT-PCR and in situ hybridization. The mRNA rescue experiment validated the specificity of the morpholino knockdown. We found that the interactions among gata5, gata6, otx2 and prdm1a determine the initial specification of the zebrafish endoderm. Although otx2 can activate both gata5 and gata6, and the prdm1a/krox homologue also activates some endoderm transcription factors, a feedback loop from Gata to otx2 and prdm1a is missing. Furthermore, we found the positive regulation between gata5 and gata6 to further lock-on the mesendoderm specification by the Gata family. Chromatin immunoprecipitation was used to further validate the recruitment of Otx2 to the gata5 and gata6 loci. Functional assays revealed that module B of gata6 and the basal promoter of gata5 drive the gene at the mesendoderm, and mutational analysis demonstrated that Otx2 and Gata5/6 contribute to reporter gene activation. This is the first direct evidence for evolutionarily conserved endoderm specification across echinoderms and vertebrates.


Asunto(s)
Secuencia Conservada/genética , Endodermo/embriología , Evolución Molecular , Redes Reguladoras de Genes/genética , Proteínas de Pez Cebra/metabolismo , Pez Cebra/embriología , Pez Cebra/genética , Animales , Secuencia de Bases , Tipificación del Cuerpo/efectos de los fármacos , Tipificación del Cuerpo/genética , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Endodermo/efectos de los fármacos , Endodermo/metabolismo , Epistasis Genética/efectos de los fármacos , Factores de Transcripción GATA/genética , Factores de Transcripción GATA/metabolismo , Factor de Transcripción GATA5/genética , Factor de Transcripción GATA5/metabolismo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Sitios Genéticos/genética , Datos de Secuencia Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Oligonucleótidos Antisentido/farmacología , Factores de Transcripción Otx/genética , Factores de Transcripción Otx/metabolismo , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Unión Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reproducibilidad de los Resultados , Factores de Tiempo , Proteínas de Pez Cebra/genética
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 297-301, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22512155

RESUMEN

Based on the theoretical models of computing the photocathode optical performance, quantum yield and integral sensitivity, the photoemission characteristics of the domestic and ITT's transmission-mode extended blue GaAs photocathodes, namely the cathode optical properties and performance parameters, were respectively investigated. The compared results show that the integral sensitivity of the domestic transmission-mode extended blue photocathode has achieved 2,100 microA x lm(-1), still falling behind the ITT's integral sensitivity of 2,750 µA x m(-1). The reasons for the difference in quantum yield curves are that, on one hand, the thickness of GaAlAs window-layer and the Al mole fraction play a critical role in the short-wavelength response, especially in the extended blue region. On the other hand, the cathode performance parameters such as electron diffusion length and back interface recombination velocity work on the long-wavelength and short-wavelength response. All these factors are subject to the backwardness of basic industrial manufacturing level.

10.
Front Rehabil Sci ; 3: 879898, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36188921

RESUMEN

To assess activity and participation for adults in Taiwan's Disability Eligibility Determination System (DEDS), we developed a measure, the Functioning Disability Evaluation Scale-Adult version (FUNDES-Adult), based on the 36-item interviewer-administered version of the WHO Disability Assessment Schedule 2.0. The purpose of this study was to examine the factor structures of performance and capability dimensions of the FUNDES-Adult. This study followed a methodology research design to investigate the construct validity of the two dimensions of the FUNDES-Adult. Two samples were randomly stratified from the databank of adults with disabilities to examine structural validity by the exploratory factor analysis (EFA) (n = 8,730, mean age of 52.9 ± 16.81) and the confirmatory factor analysis (CFA) (n = 500, mean age of 54.3 ± 16.81). The results demonstrated that the EFA yielded 5-factor structures for both performance dimension (73.5% variance explained) and capability dimension (75.9% variance explained). The CFA indicated that the second-order factor structures of both dimensions were more parsimonious with adequate fit indices (GFI, NFI, CFI, and TLI ≥ 0.95, RMSEA < 0.09). The results of this study provide evidence that the FUNDES-Adult has acceptable structural validity for use in Taiwan's DEDS. Utility of the FUNDES-Adult in rehabilitation, employment, welfare, and long-term care services needs further study.

11.
J Neurophysiol ; 106(2): 801-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21593391

RESUMEN

Tobacco use is a major public health problem, and although many smokers report that they want to quit, only a small percentage succeed. Side effects associated with nicotine withdrawal, including depression, anxiety, and restlessness, certainly contribute to the low success rate. The dorsal raphe nucleus (DRN) is a serotonergic center with many functions, including control of mood and emotional state. We investigated the effect of nicotine on DRN neurons that project to the nucleus accumbens (NAc), an area involved in reward-related behaviors. Using a retrograde labeling method, we found that 75% of DRN-NAc projection neurons are serotonergic. In coronal slices that include the DRN, whole cell recordings were conducted on neurons identified by fluorescent backlabeling from NAc or randomly selected within the nucleus. Nicotine increased action potential firing rates in a subset of DRN neurons. Voltage-clamp recording revealed nicotinic acetylcholine receptor (nAChR)-mediated inward currents that contribute to the nicotine-induced excitation. Nicotinic receptors also indirectly affect excitability by modulating synaptic inputs to these neurons. Nicotine enhanced excitatory glutamatergic inputs to a subset of DRN-NAc projection neurons, while inhibitory γ-aminobutyric acid (GABA)ergic inputs were modulated either positively or negatively in a subset of these neurons. The net effect of nAChR activation is enhancement of serotonergic output from DRN to the NAc, which may contribute to the effects of nicotine on mood and affect.


Asunto(s)
Potenciales Postsinápticos Excitadores/fisiología , Potenciales Postsinápticos Inhibidores/fisiología , Nicotina/farmacología , Núcleo Accumbens/fisiología , Núcleos del Rafe/fisiología , Neuronas Serotoninérgicas/fisiología , Animales , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Masculino , Núcleo Accumbens/efectos de los fármacos , Técnicas de Cultivo de Órganos , Núcleos del Rafe/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Neuronas Serotoninérgicas/efectos de los fármacos
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(10): 2655-8, 2011 Oct.
Artículo en Zh | MEDLINE | ID: mdl-22250528

RESUMEN

GaN photocathode has a wide applicaion in ultraviolet detection because of the outstanding performance. GaN photocathode was activated in ultrahigh vacuum (UHV) system by Cs/O, and the reflection-mode quantum efficiency (QE) was analyzed. The QE is 30%-10% corresponding to the wavelength 240-350 nm, and the QE curve is flat. The QE reaches the maximum of 30% at 240 nm. Compared with the abroad result, the QE obtained by us is still inadequate at the short wavelength The atom arrangement of GaN (0001) was studied. The atom arrangement on the surface was simulated by 3D, and in this way the adsorption of Cs on the GaN(0001) was speculated.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(8): 2036-9, 2011 Aug.
Artículo en Zh | MEDLINE | ID: mdl-22007379

RESUMEN

High temperature annealing and Cs/O activation are external incentives, while the property of GaN material is internal factor in the preparation of negative electron affinity GaN photocathode. The similarities and differences of the performance of the two structure photocathodes are analysed based on the difference of the structure between uniform-doping and gradient-doping negative electron affinity GaN photocathodes and the changes in photocurrents in activation and the quantum yield after successfully activated of GaN photocathodes. Experiments show that: the photocurrent growth rate is slower in activation, activation time is longer and quantum efficiency is higher after successfully activated of gradient-doping GaN photocathode than those of uniform-doping photocathode respectively. The field-assisted photocathode emission model can explain the differences between the two, built-in electric field of gradient-doping structure creates additional electronic drift to the photocathode surface, and the probability of electrons to reach the photocathode surface is improved correspondingly.

14.
Hortic Res ; 8(1): 168, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34333518

RESUMEN

The skin protects a fruit from environmental stresses and supports the fruit's structure. Failure of the skin leads to fruit splitting and may compromise commercial production for fruit growers. The mechanical properties of the cuticle and skin cell walls might influence the splitting susceptibility of fleshy fruits. Thin shell theory and fracture mechanics were utilized in this study to target the potential factors contributing to splitting susceptibility. The study analyzed the structure of the cuticle and epidermis in ripening grape berries and examined the temporal dynamics of berry splitting. Cuticular waxes were partially removed, and skin cell walls were manipulated using wall stiffening and loosening solutions that altered reactions involving hydrogen peroxide. A more than twofold difference in cuticle thickness among grape cultivars did not account for their differences in splitting resistance. However, while removing predominantly epicuticular wax did not alter the berries' splitting resistance, their surface appearance and increasing yield strength following partial wax removal support the notion that cuticular waxes contribute to berry mechanical properties. Immersing berries in H2O2-based cell wall loosening solutions increased the splitting probability and accelerated berry splitting, whereas cell wall stiffening solutions decreased the splitting probability and delayed berry splitting. These results showed that both cuticle and skin cell walls contribute to the mechanical properties of grape berries and to their splitting resistance. The results also suggest that the two current explanations for fruit splitting, the critical turgor model and the zipper model, should be viewed as complementary rather than incompatible.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(8): 2038-42, 2010 Aug.
Artículo en Zh | MEDLINE | ID: mdl-20939302

RESUMEN

Mechanism about the change of GaAs phtotocathode's surface barrier during Cs activated process was studied. Ionized Cs and p type doping impurity(Be) form a dipole that decreases the vacuum level of GaAs. Generally, Cs activated GaAs photocathode could achieve zero electron affinity state. The quantum yield formula of reflection-mode photocathode has been solved from the 1-dimension continuity equations and the escape probability formula has been solved from the Schrodinger equation. It was found from the formula that the quantum efficiency of Cs activated GaAs photocathode is directly proportional to the electric field intensity of Be- -Cs+ dipole. A Cs activation experiment was carried out, the experiment process tallies with the theory mentioned above and the integral sensitivity of Cs activated GaAs photocathode is 453 microA x lm(-1), which could be inferred as a zero electron affinity state.

16.
Artículo en Inglés | MEDLINE | ID: mdl-32846919

RESUMEN

To assess activity and participation for children in Taiwan's Disability Eligibility Determination System (DEDS), we developed a questionnaire, the Functioning Disability Evaluation Scale (FUNDES-Child), based on the Child and Adolescent Scale of Participation (CASP). The study follows a methodology research design to investigate the construct validity of the frequency and independence dimensions of FUNDES-Child 7.0. Two samples were randomly stratified from the databank of 13,835 children and youth with disabilities aged 6.0-17.9 years to examine structural validity by exploratory factor analysis (EFA, n = 4111, mean age of 11.3 ± 3.5) and confirmatory factor analysis (CFA, n = 4823, mean age of 11.4 ± 3.5)). EFA indicated a 4-factor structure for the frequency dimension (51.3% variance explained) and a 2-factor structure for the independence dimension (53.6% variance explained). The CFA indicated that the second-order factor structures of both dimensions were more parsimonious with adequate fit indices (Goodness fit Index, GFI; Normed Fit Index, NFI; Comparative Fit Index, CFI; and Tucker-Lewis Index, TLI ≥ 0.95, Root Mean Square Error of Approximation, RMSEA < 0.06). Results provide evidence that the participation part of FUNDES-Child 7.0 has acceptable structural validity for use in Taiwan's DEDS. Utility of FUNDES-Child 7.0 in rehabilitation, welfare, and educational services needs further study.


Asunto(s)
Evaluación de la Discapacidad , Personas con Discapacidad , Determinación de la Elegibilidad , Adolescente , Niño , Femenino , Humanos , Masculino , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Taiwán
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(11): 3007-10, 2009 Nov.
Artículo en Zh | MEDLINE | ID: mdl-20101974

RESUMEN

For a quantitative analysis of the effect of varied doping structure on the quantum efficiency of cathode, two kinds of reflective gradient doping GaAs photocathode samples were designed and grown respectively. After activation, the dynamic spectral response curves of the two samples were obtained. The spectral response curves were transformed into quantum efficiency curves. The quantum efficiency curves in different wavebands were fit, and the varied doping coefficient K that reflects the contribution of the varied doping structure to the cathode quantum efficiency was obtained. Results show that, the functional effects of the same material varied doping structure responding to the incident photon of different wavebands are different from each other. The same is true for the different material varied doping structures responding to the same waveband incident photon. The fundamental reasons for these differences are that the positions and the intensities of the inside electric fields which build within the materials under different varied doping structures are different from each other. It offers an effective analysis means to evaluate the structure performance of cathodes grown under different doping ways, and has great value for the study on optimization design of cathode varied doping structure.

18.
Org Lett ; 21(5): 1497-1501, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30763110

RESUMEN

A Rh(III)-catalyzed reaction of N-methoxybenzamides and 4-diazoisochroman-3-imines is described. This method offers a rapid entry to 3-amino-4-arylisoquinolinone architectures from readily available starting materials under mild reaction conditions. A one-pot cascade C-H bond activation/formal [4 + 2] cycloaddition mechanism is proposed. The synthesized 3-amino-4-arylisoquinolinones can be conveniently converted into dibenzo[ c, f][1,8]naphthyridines.

19.
Ying Yong Sheng Tai Xue Bao ; 29(12): 4056-4062, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30584733

RESUMEN

The changes and renewal of soil quality are the criteria for judging agricultural development and soil management. The albic soil is the main paddy field soil in Sanjiang Plain. There is limited knowledge about the changes of soil quality after the dry field was changed into the paddy field. Taking albic soils from different years of rice planting as study objects, the changes of soil physical and chemical properties were investigated. The results showed that the total amount of soil organic carbon and reducing substances increased in the ploughing layer (16-23 cm thick) and the bottom ploughing layer (6-8 cm thick). The depth of ploughing layer gradually increased with the increases of rice planting years. There was no significant change after the bottom layer was changed into the paddy field. There was no significant difference in the subsoil layer (20 cm thick) compared with dryland. The Fe2+ and Mn2+ in the soil tended to migrate downward, but only to the plough bottom layer. The ratio of soil solid phase of the ploughing layer and the ploughing bottom layer increased after rice planting, with the ratio of soil solid phase of the ploughing bottom layer increased from 47.8% to 70.0% and the bulk density increased from 1.22 g·cm-3 to 1.77 g·cm-3. Decreases of the total amount of soil porosity, increases of the proportion of micropores, and cohesive leaching deposition in the albic soil were observed after rice planting. The changes of soil physical and chemical properties of albic soil after rice planting were generally consistent with the evolution of paddy soil except for several particularities.


Asunto(s)
Agricultura/métodos , Monitoreo del Ambiente , Oryza/crecimiento & desarrollo , Suelo/química , Carbono , Pradera
20.
Ann Clin Transl Neurol ; 5(1): 92-97, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29376095

RESUMEN

In this repeated measures case study, we show that sensory deafferentation after limb amputation leads to changes in cortical somatotopic maps which are reversible after restoration of sensory input. Using magnetoencephalography (MEG), we observed in a child with bilateral hand transplants large-scale shifts in somatosensory lip cortical representation from anatomic hand area to anatomic face region. After recovery of tactile sensation in the digits, responses to finger stimulation were localized to orthotopic sensory cortex, but with atypical electrophysiologic features (amplitude and frequencies).

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