CO2-pressure swing activation for efficient production of highly porous carbons

In this work, we describe a new type of activation method of carbon materials using pressure swing of CO2. The porosity development markedly depends on the pressure swinging frequency. The porous carbon obtained from pressure-swing activation shows an additional porosity development without pitting corrosion on the surface, which occurs on CO2 activation without pressure-swing. This phenomenon is ascribed to the enhancement of Knudsen diffusion and/or configurational diffusion of CO2 which is caused by an exterior stimulus from the pressure swing. (C) 2015 Elsevier Ltd. All rights reserved.ArticleCARBON. 85:245-248 (2015)journal articl

Insulin-like growth factor 1 regulates excitatory synaptic transmission in pyramidal neurons from adult prefrontal cortex

Insulin-like growth factor 1 (IGF1) influences synaptic function in addition to its role in brain development and aging. Although the expression levels of IGF1 and IGF1 receptor (IGF1R) peak during development and decline with age, the adult brain has abundant IGF1 or IGF1R expression. Studies reveal that IGF1 regulates the synaptic transmission in neurons from young animals. However, the action of IGF1 on neurons in the adult brain is still unclear. Here, we used prefrontal cortical (PFC) slices from adult mice (∼8 weeks old) to characterize the role of IGF1 on excitatory synaptic transmission in pyramidal neurons and the underlying molecular mechanisms. We first validated IGF1R expression in pyramidal neurons using translating ribosomal affinity purification assay. Then, using whole-cell patch-clamp recording, we found that IGF1 attenuated the amplitude of evoked excitatory postsynaptic current (EPSC) without affecting the frequency and amplitude of miniature EPSC. Furthermore, this decrease in excitatory neurotransmission was blocked by pharmacological inhibition of IGF1R or conditional knockdown of IGF1R in PFC pyramidal neurons. In addition, we determined that IGF1-induced decrease of EPSC amplitude was due to postsynaptic effect (internalization of a-amino-3-hydroxy-5-methyl-4- isoxazolepropionic acid receptors [AMPAR]) rather than presynaptic glutamate release. Finally, we found that inhibition of metabotropic glutamate receptor subtype-1 (mGluR1) abolished IGF1-induced attenuation of evoked EPSC amplitude and decrease of AMPAR expression at synaptic membrane, suggesting mGluR1-mediated endocytosis of AMPAR was involved. Taken together, these data provide the first evidence that IGF1 regulates excitatory synaptic transmission in adult PFC via the interaction between IGF1R-dependent signaling pathway and mGluR1-mediated AMPAR endocytosis

Comparative pore structure analysis of highly porous graphene monoliths treated at different temperatures with adsorption of N-2 at 77.4 K and of Ar at 87.3 K and 77.4 K

We prepared nanoporous graphene monolith of different porosity by high temperature treatment up to 2073 K in Ar. The porosity is comparatively evaluated with N-2 adsorption isotherms at 77.4 K and Ar adsorption isotherms at 87.3 K and 77.4 K. N-2 adsorption at 77.4 K shows an excess adsorption amount below 3 x 10(-3) of the relative pressure which is caused by the quadrupole moment of an N-2 molecule. This effect doesn't give significant influence on the determination of the total surface area from subtracting pore effect (SPE) method, the micropore volume from Dubinin-Radushkevich (DR) method and the total pore volumes from the Gurvitch rule. However, the peak of the micropore size distribution determined by Horvath-Kawazoe (HK) method from N-2 adsorption at 77.4 K shifts to a smaller size than that from Ar adsorption at 87.3 K by 0.05-0.09 nm. (C) 2015 Elsevier Inc. All rights reserved.ArticleMICROPOROUS AND MESOPOROUS MATERIALS. 209:72-78 (2015)journal articl

Control Strategy and Simulation of the Regenerative Braking of an Electric Vehicle Based on an Electromechanical Brake

The electromechanical brake (EMB) has very broad prospects for application in the automotive industry, especially in small- and medium-sized vehicles. To extend the endurance range of pure electric vehicles, a regenerative braking control strategy combined with an electromechanical brake model is designed that divides the braking modes according to the braking intensity and controls the regenerative braking force based on fuzzy theory. Considering a front-wheel-drive pure electric vehicle equipped with a floating clamp disc electromechanical brake as the research object, a structural form of electromechanical brake is proposed and a mathematical model of the electromechanical brake is built. Combined with the relevant influencing factors, the regenerative braking force is limited to a certain extent, and the simulation models of the electromechanical brake and the regenerative braking force distribution control strategy are built in MATLAB/Simulink. Co-simulation in MATLAB and AVL CRUISE software is conducted. The simulation results demonstrate that the braking energy recovery rate of the whole vehicle with the fuzzy control strategy put forward in this paper is 28.9% under mild braking and 34.11% under moderate braking. The control method substantially increases the energy utilization rate

A Case Report of Tragaxofusp Causing Severe Tumor Lysis Syndrome In A Patient With Blastic Plasmacytoid Dendritic Cell Neoplasm

The patient was an 83-year-old male without significant past medical hsitory who presented to his primary care physician with several days of generalized malais

Dynamic reliability using entry-time approach for maintenance of nuclear power plants

Entry-time processes are finite-state continuous-time jump processes with transition rates depending only on the two states involved in transition, the calendar time, and the most recent arrival time, which is termed as entry-time. The entry-time processes have the potential to provide a significantly greater range of applicability and flexibility than traditional reliability tools for case studies related to equipment and components in nuclear power plants. In this dissertation, the finite difference approximation of the integrodifferential Chapman-Kolmogorov equations for the entry-time processes was developed, and then it was verified by application to some hypothetical examples that are solved by alternative means, either (semi-)analytically or via simulation. To demonstrate the ability of entry-time model to applications in nuclear power plants for a RIAM based scenario, the entry-time approach is applied to the maintenance of main generators in nuclear power using the data from INPO-EPIX database. In this application, both reliability and financial performances acquired using the entry-time approaches corresponding to different maintenance policies are presented and discussed to help make maintenance decisions for the plant management. The ability of the EPIX database to provide time-dependent failure rates is demonstrated and the techniques for extraction of failure rates from the database for main generators are also discussed

Evaluation of Miniaturized Mixer and Integrated Optical Components for Cell Sorting

Conventional cell cytometers are often bulky and thus not convenient for bio-medical analysis where portable devices are desired. They also suffer from the drawback of high cost due to the complicated and expensive optical detection system involved. Therefore miniaturizing conventional cell cytometer is highly demanded as it offers an opportunity to transform the conventional bulky systems to more cost-efficient and portable microfluidic cell sorting devices. In addition to the advantages reduced cost and enhanced portability, microfluidic cell sorting devices require only a tiny amount of sample for analysis. In this thesis, one common microfluidic cell sorting device is developed using similar conventional functions and concepts but different sorting method. Unlike most of the conventional cell cytometers in which an electrical field or magnetic field is employed to deflect the charged target cells to the collecting container, microfluidic cell sorting devices use the fluid flow to control the movement of the targeted cells to the collecting reservoir. By using an electroosmitic pump, the response time of the flow switch is significantly lowered, leading to a much higher sorting efficiency. Despite the advantages of microfluidic cell sorting devices, there are some issues need to be addressed before realization of such devices. For example, more studies are required on the successful integration of the optical elements in the devices. In microfluidic, the transport phenomena is also different from that in macroscopic. Unlike that in macroscopic, surface forces are important in microfluidics. They result in pressure-induced flow which gives the parabolic profile of the velocity along the channel. Also, a plug-like velocity which is generated by the electoosmitic flow is required for the more controllable and accurate detection. To suppress the pressure-driven flow, hydro-resistance elements (Shallow channel network) are implemented on the microfluidic devices. Fabrication of optical elements by deposition of optical materials on glass or silicon wafer has been reported. However, this Micro Electro-Mechanical (MEM) technique requires special equipment and cleanroom facilities used in the semiconductor industry. A good alternative to the MEMS technique is soft lithography where optical elements can be created using polymers. In this work, ultraviolet-sensitive photo resists SU8 is used to fabricate the microfluidic cell sorting devices and the optical elements. By using the mask with the patterns of the microchannel network and optical elements, the optical elements can be fabricated with the microchannel, eliminating the problem of alignment. Experiments are also conducted to evaluate the integrated optical elements. To prevent cross-contamination, samples are usually prepared and are only mixed inside the microfluidic devices by the embedded mixers. Such embedded mixers, however, pose a great challenge as the small characteristic length of a microfluidic device tends to give a laminar flow and diffusion-dominated mixing. A simple passive micromixer is investigated to find the possibilities to integrate it to the microfluidic devices. To truly understand the diffusional mixing, a Y channel mixer is studied through the numerical and experimental investigations. Based on the results found, a possible design is also proposed and evaluated by experiments

Mapping of Quantitative Traits Important to Dual-purpose Management of Winter Wheat

In the southern Great Plains, winter wheat is widely used for forage-plus-grain production. Knowledge of the genetic control of traits important to dual-purpose management would facilitate breeding efforts leading to better adapted cultivars. Linkage mapping was conducted on 94 recombinant inbred lines derived from two locally adapted cultivars, `Intrada' and `Cimarron'. Single-marker analysis and interval mapping methods were applied to identify putative QTLs. Traits including initial stem elongation, heading date, and high-temperature seed dormancy, were investigated in the field at Stillwater, Oklahoma from 2004 to 2007.A linkage map was completed with 243 SSR, SNP, or gene markers, covering 15 wheat chromosomes and uncharacterized small linkage groups. Three QTLs in the photoperiod pathway interactively regulated both initial stem elongation and heading. The Intrada Xbarc200 and Xcfd14 alleles and the Cimarron PPD-D1 allele accelerated stem elongation and heading stages; conversely, the Cimarron Xbarc200 and Xcfd14 alleles and the Intrada PPD-D1 allele delayed stem elongation and heading stages. Regarding high-temperature seed dormancy, two major QTLs were detected on chromosomes 3AS and 4AL, matching QTLs previously known to control warm-temperature seed dormancy. The Cimarron Xbarc310 and Xzxq118 alleles promoted sensitivity to high temperature. Grain color had no significant association with expression of high-temperature seed dormancy. Our results showed that initial stem elongation vs. heading, or high vs. warm temperature seed dormancy, were interrelated by common genetic loci. Careful selection of alleles is required to enhance the adaptation of winter wheat to dual-purpose management systems.Department of Plant and Soil Science