Method to Characterize the Air Flow and Water Removal Characteristics During Vacuum Dewatering. Part II—Analysis and Characterization

This is part II of a study reported earlier on a method to characterize the air flow and water removal characteristics during vacuum dewatering. This article presents experimental data and analysis of results from the use of a cyclically actuated vacuum dewatering device for removing moisture from wetted porous materials such as paper with the intermittent application of vacuum and accompanying air flow though the material. Results presented include sheet moisture content as a function of residence time and hence water removal rate under a variety of process conditions. Also, experimental results on air flow through the wet porous structure and hence the role and importance of air flow during vacuum dewatering are presented. Vacuum dewatering process conditions include exit solids content between 11 and 20% solid under applied vacuum conditions of 13.5 to 67.7 kPa (4 to 20 in. Hg). Regression analysis indicated that the exit sheet moisture content exhibited a nonlinear relationship with residence time with exit solids reaching a plateau after a certain residence time. Final moisture content correlated linearly with the average overall flow rate of air through the paper sample and the basis weight of the material.     

Smoke suppressants for plasticized poly(vinyl chloride)

Addition of plasticizers to poly(vinyl chloride) generally increases its flammability and frequently increases smoke production during its burning. Flame retardants added to plasticized PVC can reduce flammability, but increase smoke production. This study shows that proper choice of combined use of other polymers, phosphate plasticizers, fillers and other flame retardants, produces measured synergistic improvements in flame retardance and smoke suppression which could benefit applications such as PVC wire and cable insulation.     

Formulae for determining heterodyne system spurious frequencies that coincide with desired output frequency

In this paper, formulae to determine the lowest order and other higher order spurious frequencies that coincide with desired output signal frequencies of mixers have been derived. The proposed formulae give general expressions that are suitable for any order of heterodyne mixing. The formulae have been verified using a suitable example and compared with the simulation results obtained through the radio frequency simulation software of Advanced Design System. The formulae directly reveal the order of the troublesome spurious frequencies that the designers would encounter in heterodyne systems. In comparison with these direct formulae, the results of existing spurious analysis software are based on the maximum order of simulation carried out. Based on these simulations, the coinciding spurious components have to be manually sorted out. Proposed formulae are quick tools used by the microwave system and circuit designers for choosing and finalizing heterodyne frequencies in their designs without the need for any simulations.     

Scalable approach to uncertainty quantification and robust design of interconnected dynamical systems

Development of robust dynamical systems and networks such as autonomous aircraft systems capable of accomplishing complex missions faces challenges due to the dynamically evolving uncertainties coming from model uncertainties, necessity to operate in a hostile cluttered urban environment, and the distributed and dynamic nature of the communication and computation resources. Model-based robust design is difficult because of the complexity of the hybrid dynamic models including continuous vehicle dynamics, the discrete models of computations and communications, and the size of the problem. We will overview recent advances in methodology and tools to model, analyze, and design robust autonomous aerospace systems operating in uncertain environment, with stress on efficient uncertainty quantification and robust design using the case studies of the mission including model-based target tracking and search, and trajectory planning in uncertain urban environment. To show that the methodology is generally applicable to uncertain dynamical systems, we will also show examples of application of the new methods to efficient uncertainty quantification of energy usage in buildings, and stability assessment of interconnected power networks.     

碳纳米管阵列/热解炭复合材料的制备和表征（英文）

以甲烷为碳源,通过化学气相沉积和化学蒸汽渗透两步法将热解炭填充至碳纳米管阵列间的空隙而制备出碳纳米管阵列/热解炭复合材料。采用扫描电镜和拉曼光谱仪对样品的结构进行表征。结果表明,碳纳米管被热解炭填充和覆盖形成均相的复合膜,其密度增加4倍,同时热解炭已石墨化。     

Optimizing PSMA Radioligand Therapy for Patients with Metastatic Castration-Resistant Prostate Cancer. A Systematic Review and Meta-Analysis

The aim of the review was to evaluate patient and treatment characteristics for patients with metastatic castration-resistant prostate cancer (mCRPC) treated with PSMA radioligand therapy (PRLT) associated with above-average outcome. The systematic review and meta-analysis followed recommendations by the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA). We searched for publications in PubMed, Embase, and ClinicalTrials.gov up to 31 September 2020. Thirty-six publications and four duplicates reported 2346 patients. Nearly two-thirds of the patients had bone metastases. Median overall survival (OS) was 16 months. Asymptomatic patients and patients with only lymph node metastases lived longer than symptomatic patients and patients with more extensive metastases. Patients treated with an intensified schedule of ¹⁷⁷Lu PRLT lived longer than those treated with a conventional schedule. Half of the patients obtained a PSA decline ≥ 50% and these patients lived longer than those with less PSA decline. Approximately 10% of the patients developed hematologic toxicity with anemia grade 3 as the most severe adverse effect. Characteristics for patients, cancer, restaging, and PRLT predict above average overall survival following treatment with PRLT.     

Effect of Conjugate Heat Transfer on Entropy Generation in Slip-Driven Microflow of Power Law Fluids

We analyze the entropy generation characteristics in a non-Newtonian microflow under the influence of interfacial slip as modulated by the conjugate transport of heat. We consider power law model to represent the constitutive behavior of the non-Newtonian fluid. In this analysis, we analytically solve the transport equations employing the thermal boundary condition of the third kind at the exterior wall surface accounting for the effect of conjugate heat transfer. We demonstrate that the slip flow–driven alteration in convective transport of heat and its nonlinear interaction with viscous dissipation, as modulated by fluid rheology and conjugate transport of heat, gives rise to a minimum entropy generation rate of the system. We determine the optimum value of the geometrical parameter—that is, the channel wall thickness and the thermophysical parameters, such as the Biot number and Peclet number—leading to a minimum entropy generation rate in the system. The results of this analysis could be of helpful in designing microsystems/devices typically used for electronic cooling, micro-heat pipes, and micro-heat exchangers.     

An Indian test facility to characterise diagnostic neutral beam for ITER

The diagnostic neutral beam (DNB) line shall be used to diagnose the He ash content in the D–T phase of the ITER machine using the charge exchange recombination spectroscopy (CXRS). Implementation of a successful DNB at ITER requires several challenges related to the production, neutralization and transport of the neutral beam over path lengths of 20.665 m, to be overcome. The delivery is aided if the above effects are tested prior to onsite commissioning. As DNB is a procurement package for INDIA, an ITER approved Indian test facility, INTF, is under construction at Institute for Plasma Research (IPR), India and is envisaged to be operational in 2015. The timeline for this facility is synchronized with the RADI, ELISE (IPP, Garching), SPIDER (RFX, Padova) in a manner that best utilization of configurational inputs available from them are incorporated in the design. This paper describes the facility in detail and discusses the experiments planned to optimise the beam transmission and testing of the beam line components using various diagnostics.     

An analytical model to predict specific shear energy in high-speed turning of Inconel 718

Machining of Inconel 718 at higher cutting speeds is expected to provide some relief from the machining difficulties. Therefore, to understand the material behavior at higher cutting speeds, this paper presents an analytical model that predicts specific shearing energy of the work material in shear zone. It considers formation of shear bands that occur at higher cutting speeds during machining, along with the elaborate evaluation of the effect of strain, strain rate, and temperature dependence of the shear flow stress using Johnson–Cook equation. The model also considers the ‘size-effect’ in machining in terms of occurrence of ‘ploughing forces’ during machining. The theoretical results show that the shear band spacing in chip formation increases linearly with an increase in the feedrate and is of the order of 0.2–0.9 mm depending upon the processing conditions. The model shows excellent agreement with the experimental values with an error between 0.5% and 7% for various parametric conditions.