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Development of efficient surface passivation methods for semiconductor devices is crucial to counter the degradation in their electrical performance owing to scattering or trapping of carriers in the channels induced by molecular adsorption from the ambient environment. However, conventional dielectric deposition involves the formation of additional interfacial defects associated with broken covalent bonds, resulting in accidental electrostatic doping or enhanced hysteretic behavior. In this study, centimeter-scaled van der Waals passivation of transition metal dichalcogenides (TMDCs) is demonstrated by stacking hydrocarbon (HC) dielectrics onto MoSe

Ultrathin uracil-complexed CdS nanowires (U-CdS NWs) were synthesized using a facile wet-chemical process and exploited as an effective electron transport layer (ETL) in organic solar cells (OSCs). The U-CdS NW layer acted as a functional interfacial layer between the active organic and inorganic ZnO films; the functional N H and C O groups in uracil passivated the ZnO surface defects and CdS provided a favorable energy band alignment, which facilitated electron transportation. As a result, the power-conversion efficiency (PCE) of the OSC with U-CdS NWs was 3.52% (maximum PCE of 3.7%), which was 22% higher than that of an OSCs with bare ZnO. Moreover, OSCs with U-CdS NWs had two times longer storage lifetimes because of the enhanced interfacial quality and the hydrophobic nature of U-CdS NWs. These results demonstrate the potential of U-CdS NWs for enhancing the efficiency and stability of OSCs and represent an important step toward the commercialization of OSCs.

New high-k gate dielectrics are highly necessary in facilitating the continuous down-scaling of metal–oxide–semiconductor devices to the sub-10 nm range. This study presents ultrathin organic hydrocarbon (HC) films as a novel high-k gate insulator for metal–insulator–semiconductor (MIS) devices. During inductively-coupled plasma chemical vapor deposition with CH4 and H2 gases, the growth temperature greatly affects the structure of the carbon layers and consequently their dielectric characteristics. Specifically, sp2-rich dielectric HC layers are formed below 600 °C, whereas highly-ordered sp2-hybridized graphene is formed at 950 °C. The k value of the resulting HC films increases up to a maximum value of 90 at 350 °C. Moreover, the MIS devices exhibit excellent gate-insulating properties, including almost no hysteresis in the capacitance–voltage curve, low leakage current, and high dielectric strength, which surpass those of existing high-k gate oxides. These results reveal that the organic HC films are a promising next-generation high-k gate dielectric material for sub-10 nm node Si and organic semiconductor technologies.

Solar absorber Cu2ZnSnS4 (CZTS) films were uniformly deposited on Si/Mo substrates via a facile, cost-effective chemical bath deposition (CBD) by using ribonucleic acid (RNA) nucleobase uracil as the functional building block. The functional sites of uracil, i.e., C O and N H, played a critical role in the complexation of metals via uracil-quartet functional architectures. Stable metal–uracil complexes significantly affected the growth kinetics, enhancing the uniform delivery of multimetal components into films and suppressing the undesirable formation of CuS particles. CZTS films obtained with the addition of 0.05 and 0.5 M uracil exhibited a smooth surface morphology and significantly improved photoconductive performance. The developed RNA-nucleobase-mediated CBD method demonstrates promise as multicomponent compound absorber films, including CZTS and CuInGaSe2, in cost-effective solar cells.

Efficient visible-light photocatalysis was realized by exploring self-induced defect states, including the abundant surface states of TiO2-δ nanobelts synthesized through metal–organic chemical vapor deposition (MOCVD). The TiO2-δ nanobelts exhibited two strong defect-induced absorption peaks at 2.91 and 1.92 eV, overlapping with the conduction band states so that photoexcited carriers can contribute effectively for the photocatalysis reaction. To further enhance visible-light photocatalytic activity, carbon atoms, the by-product of the MOCVD reaction, were self-doped at the judiciously determined growth conditions. The resulting visible-light photocatalysis suggests that the large surface area and consequent high concentration of the surface states of the TiO2-δ nanobelts can be effectively utilized in a wide range of photocatalysis applications.

Vertically-standing, few-layer MoS2 flakes were uniformly and conformally grown on closely-packed TiO2 nanowire substrates using metal-organic chemical vapor deposition. The TiO2/MoS2 heterostructures exhibited remarkably improved photoelectrochemical (PEC) performance and long-term stability owing to enhanced photogenerated electron–hole separation and transfer properties across the heterojunction. Due to the built-in heterojunction potential, the onset potential of TiO2/MoS2 heterostructures was cathodic-shifted to −0.3 V, thereby resulting in maximum PEC reactivity at approximately zero potential. In contrast, MoS2 flakes on fluorine-doped tin oxide substrates exhibited an onset potential of approximately 0.3 V. Furthermore, PEC performance was critically affected by the size of the vertically-standing MoS2 flakes, indicating that controlled conformal growth of MoS2 flakes on appropriate nanostructures is essential to exploit these nanostructures as efficient, non-toxic, inexpensive, and earth-abundant PEC electrodes.

One-dimensional (1D) WO3/two-dimensional (2D) WS2 heterojunction nanostructures are of great interest in various photoelectrochemical (PEC) and electrochemical applications. In this study, we introduced a simple and effective route to synthesize 2D WS2 shell layer on WO3 nanorods by utilizing WO3∙0.33H2O phase. The formation of WO3∙0.33H2O nanorods was critically affected by hydrothermal reaction temperature. The WO3∙0.33H2O phase was preferentially transformed into hexagonal WO3 and 2D WS2 through oxidation and sulfurization at 450 °C, respectively. The 2D WS2 shell layer was more favorably formed on WO3 nanorods, which were synthesized at 180 °C and possessed a significant amount of WO3∙0.33H2O phase (referred to as W-180), than on WO3 nanorods with predominant monoclinic WO3 phase, which were synthesized at 200 °C (referred to as W-200). Thus, the WO3/WS2 core@shell nanorods from W-180 exhibited significantly enhanced PEC performance because of the improved charge transfer properties attributed to the advantageous heterojunction effect of 1D WO3/2D WS2. The new synthesis route from WO3∙0.33H2O phase to 2D WS2 can be applied to synthesize various WO3/2D WS2 heterojunction nanostructures, such as thin films, nanoparticles, and nanorods.

Severe charge recombination and poor water oxidation kinetics limit the performance of hematite-based (Fe2O3) photoanodes far from their theoretical levels and restrict their applicability for photoelectrochemical (PEC) water splitting devices. In this study, a hierarchical tubular structure (HTS) CoP/SnO2:Fe2O3 with a large surface area and well-defined crystalline structures was fabricated via a facile template-engaged redox etching method. The SnO2 nano-layer served as a dopant source to improve the bulk charge carrier transport efficiency along the Fe2O3 HTS growth axis; therefore, the achieved photocurrent could be up to 2.0 mA cm−2 at 1.23 VRHE (V vs. reversible hydrogen electrode). The CoP nanoparticles (NPs) were introduced as a high-speed hole collector from the light-absorber layer as well as a catalyst to enhance charge carrier injection efficiency on the photoelectrode surface. As a result, CoP/SnO2:Fe2O3 shows the highest photocurrent density of 3.50 mA cm−2 (at 1.23 VRHE) with a negative shift in the onset potential of 180 mV.

In Message Oriented Middleware are composed of semiautonomous, heterogeneous, and independently designed next generation framework. For described to achieve successful operation of such a system, the activities of the message controlling the subsystems have to be coordinated. In addition, each layer applications can require synchronizes on events relative to message availability. A common way to proceed is to implement polling strategies within the distributed components, which leads to an increase of the load in the overall system. This approach are than describe a different based on informing using oriented message queuing. The message queuing processing of this technology in the multi business domain distributed system has been exercised.

We report on the synthesis of few−layers MoS2 flakes coated on the p−Si nanorods (p−SiNRs) via the metalorganic chemical vapor deposition (MOCVD) method. The MoS2 flakes show a vertically−standing, few−layers (10–15) morphology. The photoluminescence characteristic of the MoS2/p−SiNRs heterojunction exhibits a blue−shift energy bandgap (1.65−1.78 eV) at temperature of 77 K with thinner MoS2 layers due to the quantum confinement effect. As a result, the fabricated MoS2/p−SiNRs photocathode results in a saturated photocurrent density (PCD) and a photoconversion efficiency (η) of 42.3 mA cm−2, and 0.64% at 0 V (vs. RHE), respectively. Due to the built−in potential of heterojunction and more active edge sites, the onset voltage of the MoS2/p−SiNRs sample was positively shifted to ~0.72 V (vs. RHE). Based on this finding, we suggest that a heterojunction structure might serve an approach for fabricating the hybrid photoelectrochemical (PEC) device of the Si−based material.

Two-dimensional (2D) SnS2 nanosheets vertically grown on graphene electrodes have still not been demonstrated despite their considerable research interest and potential for photoelectrochemical (PEC) applications. Herein, the controllable growth and enhanced PEC water-splitting performance of vertically aligned 2D SnS2 nanosheets on graphene are reported. The heterojunction quality of the graphene/2D SnS2 nanosheets was ensured by low-temperature growth at 230 °C using metalorganic chemical vapor deposition, resulting in significantly improved charge transfer properties. The PEC photocurrent density and photoconversion efficiency significantly increased upon insertion of a graphene layer. In addition, the 2D SnS2 nanosheet microscopic structure dependency of the PEC performance was systematically studied. The best PEC reactivity of the 2D SnS2 nanosheets was achieved at a height of ∼0.85 µm, corresponding to nearly the limit of the carrier diffusion length, and a thickness of ∼70 nm to balance the low interfacial contact resistance with an effective photogenerated carrier dynamics. These results, including the low-temperature vertical growth of 2D SnS2 on graphene, can effectively be utilized to exploit the full potential of 2D SnS2 for various PEC applications.

We report on photoelectrochemical (PEC) characteristic of a few–layer MoS2–flakes deposited ZnO nanorod (MS–ZNR) configuration prepared via the hydrothermal and the metal–organic chemical vapor deposition (MOCVD) approach. The MS–ZNR nanostructure exhibited enhanced photoexcited electron-hole pair separation and transfer for energy–storage/or conversion applications. Due to a suppressing the recombination mechanism of charge carriers, the PEC performance of MS–ZNR photoelectrode revealed higher photocurrent density (1.42 mA.cm–2 at 0.2 V, η = 0.91%, with 0.1 M Na2S electrolyte) than a ZnO NR photoelectrode. We propose a potential application of MoS2–flakes hybrid nanostructure as enhanced efficient, inexpensive, and non–noble metal for PEC devices.

In this paper, we describe GCUCE (Grid Computing for Ubiquitous Computing Environment), which supports the unified efficient ubiquitous service interacting with Grid service modules using Access Grid computing. Also, we describe two mobility models: enterprise model and automata model. The former is focused on the service demand aspects, and the latter concentrates on the state transition. Based on those models, we shall show the performance of GCUCE by evaluating several experiments for DOWS (Distributed Object-oriented Wargame Simulation). The two models comprising enterprise model and automata model of software state suggest the formal and mathematical model about software mobility in GCUCE, and provide the overall views and direction of ubiquitous software development.

This study reports the effect of doping level on the performance of InAs/GaAs quantum-dot infrared photodetectors (QDIPs). Two QDIP samples were prepared via molecular beam epitaxy: n+-i(QDs)-n+ QDIP with undoped quantum dot (QD) active region, referred to as undoped QDIP, and n+-n(QDs)-n+ QDIPs intended to contain two electrons per QDs, referred to as doped QDIP. InAs self-assembled QDs were grown on GaAs (001) wafers by three mono-layers of InAs deposition. Both QDIPs showed a photoluminescence peak at 1.182 μm as well as a similar broad photocurrent (PC) spectrum peaked at about 7.5 μm, ranging from 4 μm to 9 μm at 5 K. Undoped QDIP yielded a PC spectrum of up to 100 K, whereas doped QDIP had a PC spectrum of up to 40 K only. This finding was mainly attributed to the lower dark current properties of undoped QDIP. Undoped QDIP at 77 K showed five orders of magnitude lower than the dark current of doped QDIP at 5 K.

In systemic lupus erythematosus (SLE), acute renal failure (ARF) is usually associated with severe lupus nephritis and ARF associated with other glomerular diseases is extremely rare. We recently encountered a patient with ARF that was associated with a minimal change nephrotic syndrome (MCNS) in SLE. A 41-year-old woman presented with a nephrotic syndrome and ARF. She fulfilled four of the American College of Rheumatology criteria for the classification of SLE. However, a renal biopsy revealed that there were no glomerular abnormalities and no deposition of immune complex. The generalized edema disappeared and the high creatinine levels decreased after prednisolone therapy.

Background : Perfusion scans are accurate predictors of postoperative lung function. There are few previous studies aimed at predicting the postoperative exercise capacity using the perfusion scanning and those that did reported contradictory results. Method : We prospectively studied the preoperative spirometric, exercise tests and perfusion scans from in 49 consecutive patients who were admitted to Inha University Hospital with surgically resectable lung cancer from Jan. 1998 to Jun. 1999 29 patients who had any condition affecting the lung function and exercise capacity, or refused a surgical resection or a follow-up study were excluded. Spirometric and exercise tests were performed 6 months after operation in 20 patients. Results : The predicted postoperative , FVC and TLC correlated well with the following corresponding postoperative values : and p value, 0.809 and 0.000 for the 0.895 and 0.000 for the FVC ; 0.741 and 0.006 for the TLC, respectively. The measured postoperative exercise values were slightly higher than the postoperative exercise values predicted, and , were as 112% of predicted and 119% of predicted. The change in , FVC and TLC had a weak correlation with the change in and . Conclusion : The perfusion scan was a useful tool for predicting the postoperative exercise capacity. However, they had a tendency to underestimate the exercise capacity, especially in the patients who had a pneumonectomy. A weak correlation between the change in lung function and exercise capacity was observed.