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991.
Tunable Luminescent Carbon Nanospheres with Well‐Defined Nanoscale Chemistry for Synchronized Imaging and Therapy 下载免费PDF全文
Prabuddha Mukherjee Santosh K. Misra Mark C. Gryka Huei‐Huei Chang Saumya Tiwari William L. Wilson John W. Scott Rohit Bhargava Dipanjan Pan 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(36):4691-4703
In this work, we demonstrate the significance of defined surface chemistry in synthesizing luminescent carbon nanomaterials (LCN) with the capability to perform dual functions (i.e., diagnostic imaging and therapy). The surface chemistry of LCN has been tailored to achieve two different varieties: one that has a thermoresponsive polymer and aids in the controlled delivery of drugs, and the other that has fluorescence emission both in the visible and near‐infrared (NIR) region and can be explored for advanced diagnostic modes. Although these particles are synthesized using simple, yet scalable hydrothermal methods, they exhibit remarkable stability, photoluminescence and biocompatibility. The photoluminescence properties of these materials are tunable through careful choice of surface‐passivating agents and can be exploited for both visible and NIR imaging. Here the synthetic strategy demonstrates the possibility to incorporate a potent antimetastatic agent for inhibiting melanomas in vitro. Since both particles are Raman active, their dispersion on skin surface is reported with Raman imaging and utilizing photoluminescence, their depth penetration is analysed using fluorescence 3D imaging. Our results indicate a new generation of tunable carbon‐based probes for diagnosis, therapy or both. 相似文献
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An alkaline phosphatase was purified from conidia of a Neurospora crassa wild type strain. The M(r) of the purified native enzyme was estimated as ca 145,000 and 110,000 by gel filtration, in the presence and absence of magnesium ions, respectively. A single polypeptide band of M(r) 36,000 was detected by SDS-PAGE, suggesting that the native enzyme was a tetramer of apparently identical subunits. Conidial alkaline phosphatase was an acidic protein (pl = 4.0 +/- 0.1), with 40% carbohydrate content. Optimal pH was affected by substrate concentration and magnesium ions. Low concentrations of calcium ions (0.1 mM) had slight stimulatory effects, but in excess (5 mM) caused protein aggregates with decreased activity. The enzyme specificity against different substrates was compared with those reported for constitutive or Pi-repressible alkaline phosphatases produced by N. crassa. The results suggested that the conidial alkaline phosphatase represented a different class among other such enzymes synthesized by this organism. 相似文献
994.
The scheduling problem in manufacturing is considered as among the toughest to solve. The basic drawback of many proposed methods has been the huge amount of computation time for simulation. This paper proposes a framework to solve the operation allocation problem in automated manufacturing systems using the concept of multifidelity. The concept of multifidelity has been proposed by several researchers in order to reduce the computation time for simulation. In this paper, a GA-based heuristic procedure will be developed along with the multifidelity approach to solve a typical manufacturing scheduling problem. Four different fidelity models have been defined on which experimentation is carried out. The proposed method has been tested on a sample dataset and the results have been analysed to choose the fidelity model which best describes the scenario. 相似文献
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This paper presents the performance evaluation of a hybrid photovoltaic thermal (Semi transparent PVT) double pass facade for space heating. The thermal model has been developed by using the energy balance equations of the proposed hybrid photovoltaic thermal double pass facade under quasi-steady state condition. Numerical computations have been carried out for the composite climate of New Delhi, India. An analysis has been carried out to calculate annual energy and exergy gain for the hybrid photovoltaic thermal double pass facade. On the basis of numerical results it has been observed that the annual thermal and electrical energy are 480.81 kWh and 469.87 kWh respectively. The yearly overall thermal energy generated by the system has been calculated as 1729.84 kWh. It is also observed that the room air temperature increases by 5-6 °C than the ambient air temperature for a typical winter day. 相似文献
996.
All Solution‐Processed Chalcogenide Solar Cells – from Single Functional Layers Towards a 13.8% Efficient CIGS Device 下载免费PDF全文
Yaroslav E. Romanyuk Harald Hagendorfer Patrick Stücheli Peter Fuchs Alexander R. Uhl Carolin M. Sutter‐Fella Melanie Werner Stefan Haass Josua Stückelberger Cédric Broussillou Pierre‐Philippe Grand Veronica Bermudez Ayodhya N. Tiwari 《Advanced functional materials》2015,25(1):12-27
Solution processing of inorganic thin films has become an important thrust in material research community because it offers low‐cost and high‐throughput deposition of various functional coatings and devices. Especially inorganic thin film solar cells – macroelectronic devices that rely on consecutive deposition of layers on large‐area rigid and flexible substrates – could benefit from solution approaches in order to realize their low‐cost nature. This article critically reviews existing deposition approaches of functional layers for chalcogenide solar cells with an extension to other thin film technologies. Only true solutions of readily available metal salts in appropriate solvents are considered without the need of pre‐fabricated nanoparticles. By combining three promising approaches, an air‐stable Cu(In,Ga)Se2 thin film solar cell with efficiency of 13.8% is demonstrated where all constituent layers (except the metal back contact) are processed from solutions. Notably, water is employed as the solvent in all steps, highlighting the potential for safe manufacturing with high utilization rates. 相似文献
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The objective of the study was to determine a relation for predicting convective and evaporative heat transfer coefficients for all three condensing surfaces inclined at 15°, 30° and 45° under indoor simulation. The condensing covers were made of the same flat transparent glass as found in any solar distillation unit. The operating temperature range for the experiment was maintained at steady state from 40°C to 80°C by using a constant temperature bath. The temperatures and yields obtained for a 10-min interval were used to determine the values of constants C and n and consequently convective and evaporative heat transfer coefficients. It was found that a higher yield was obtained with an increase in temperature for a 30° slope compared to 15° and 45° slopes of the condensing cover. 相似文献