Phase change materials (PCM) take advantage of latent heat that can be stored or released from a material over a narrow temperature range. PCM possesses the ability to change their state with a ...certain temperature range. These materials absorb energy during the heating process as phase change takes place and release energy to the environment in the phase change range during a reverse cooling process. Insulation effect reached by the PCM depends on temperature and time. Recently, the incorporation of PCM in textiles by coating or encapsulation to make thermo-regulated smart textiles has grown interest to the researcher. Therefore, an attempt has been taken to review the working principle of PCM and their applications for smart temperature regulated textiles. Different types of phase change materials are introduced. This is followed by an account of incorporation of PCM in the textile structure are summarized. Concept of thermal comfort, clothing for cold environment, phase change materials and clothing comfort are discussed in this review paper. Some recent applications of PCM incorporated textiles are stated. Finally, the market of PCM in textiles field and some challenges are mentioned in this review paper.
•Progress made in the field of oxy-fuel combustion-based CCS has been summarized.•Various novel oxy-fuel power plant configurations have been discussed.•Techno-economic and thermodynamic aspects of ...oxy-fuel CCS has been addressed.•Auxiliary power consumption and energy penalty of oxy-fuel PP has been examined.
Carbon capture and sequestration (CCS) technologies have emerged as a promising technique to prevent greenhouse gas emissions of fossil fuel-fired power plants. In recent years oxy-fuel combustion-based CCS technique has gained a lot of attention and consideration because of its cost-effective CO2 capture. The present review article outlines the progress made in carbon capture and sequestration (CCS) based on oxy-fuel combustion by incorporating an air separation unit (ASU) and carbon dioxide purification and compression unit (CPU). The present article discusses the major components of the oxy-fuel combustion power plant and compares various novel configurations of oxy-fuel power generation systems in terms of energy penalty, auxiliary energy consumption, CO2 purity, and CO2 capture efficiency. This review also focuses on modifications to oxy-fuel combustion power generation systems such as pressurized oxy-fuel combustion, flue gas enriched oxy-fuel combustion, and few advanced oxy-fuel configurations. This review article has addressed the techno-economic and thermodynamic aspects of the oxy-fuel combustion-based carbon capture and sequestration (CCS) method.
Produced water, water that is co-produced during oil and gas manufacturing, represents the largest source of oily wastewaters. Given high oil and gas prices, oil and gas production from ...non-conventional sources such as tar sands, oil shale and coal bed methane will continue to expand resulting in large quantities of impaired produced water. Treatment of this produced water could improve the economic viability of these oil and gas fields and lead to a new source of water for beneficial use.
Two nanofiltration and one low-pressure reverse osmosis membrane have been tested using three produced waters from Colorado, USA. The membranes were analyzed before and after produced water filtration using field emission scanning electron microscopy (FESEM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). In addition, membrane–water contact angles have been measured. XPS data indicate adsorption of organic and inorganic species during filtration. FESEM and ATR-FTIR data support theses findings. Water contact angles indicate the effect of membrane hydrophilicity on fouling. Our results highlight the value of using multiple surface characterization methods with different depths of penetration in order to determine membrane fouling. Depending on the quality of the produced water and the water quality requirements for the beneficial uses being considered, nanofiltration may be a viable process for produced water treatment.
The tailored mechanical characteristics of bioceramic scaffold are very important for the bone tissue engineering. Functional hydroxyapatite (HAp) synthesized from fish scale (Labio rohita &Catla ...catla) is explored as scaffold materials. HAp scaffold exhibits better mechanical properties such as hardness (~1.08GPa), compressive strength (~0.8GPa) and tensile strength (~187MPa) with adequate porosity (~35%) compared to commercial and synthetic body fluid derived HAp. The in vitro assays (MTT, LDH and Trypan blue) with MG63 osteoblast cell lines reveal that fish scale derived HAp materials is non-toxic and bioactive. The in vivo histological analysis of implanted HAp scaffold shows the osteo-conductive characteristics. The findings are significant with respect to cytotoxicity, osteo-conductivity and mechanical stability during bio-mineralization of traumatized bone tissues.
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•HAp scaffold exhibits better compressive (~0.8GPa) and tensile strength (~187MPa).•HAp scaffold shows the osteo-conductive characteristics.•Fish scale derived HAp materials is non-toxic and bioactive with MG63 osteoblast cell lines.
All ten LIGO/Virgo binary black hole (BH-BH) coalescences reported following the O1/O2 runs have near-zero effective spins. There are only three potential explanations for this. If the BH spin ...magnitudes are large, then: (i) either both BH spin vectors must be nearly in the orbital plane or (ii) the spin angular momenta of the BHs must be oppositely directed and similar in magnitude. Then there is also the possibility that (iii) the BH spin magnitudes are small. We consider the third hypothesis within the framework of the classical isolated binary evolution scenario of the BH-BH merger formation. We test three models of angular momentum transport in massive stars: a mildly efficient transport by meridional currents (as employed in the Geneva code), an efficient transport by the Tayler-Spruit magnetic dynamo (as implemented in the MESA code), and a very-efficient transport (as proposed by Fuller et al.) to calculate natal BH spins. We allow for binary evolution to increase the BH spins through accretion and account for the potential spin-up of stars through tidal interactions. Additionally, we update the calculations of the stellar-origin BH masses, including revisions to the history of star formation and to the chemical evolution across cosmic time. We find that we can simultaneously match the observed BH-BH merger rate density and BH masses and BH-BH effective spins. Models with efficient angular momentum transport are favored. The updated stellar-mass weighted gas-phase metallicity evolution now used in our models appears to be key for obtaining an improved reproduction of the LIGO/Virgo merger rate estimate. Mass losses during the pair-instability pulsation supernova phase are likely to be overestimated if the merger GW170729 hosts a BH more massive than 50
M
⊙
. We also estimate rates of black hole-neutron star (BH-NS) mergers from recent LIGO/Virgo observations. If, in fact. angular momentum transport in massive stars is efficient, then any (electromagnetic or gravitational wave) observation of a rapidly spinning BH would indicate either a very effective tidal spin up of the progenitor star (homogeneous evolution, high-mass X-ray binary formation through case A mass transfer, or a spin- up of a Wolf-Rayet star in a close binary by a close companion), significant mass accretion by the hole, or a BH formation through the merger of two or more BHs (in a dense stellar cluster).
The phase III MONALEESA-2 study demonstrated significantly prolonged progression-free survival (PFS) and a manageable toxicity profile for first-line ribociclib plus letrozole versus placebo plus ...letrozole in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer. Here, we report updated efficacy and safety data, together with exploratory biomarker analyses, from the MONALEESA-2 study.
A total of 668 postmenopausal women with HR+, HER2– recurrent/metastatic breast cancer were randomized (1 : 1; stratified by presence/absence of liver and/or lung metastases) to ribociclib (600mg/day; 3-weeks-on/1-week-off; 28-day treatment cycles) plus letrozole (2.5mg/day; continuous) or placebo plus letrozole. The primary end point was locally assessed PFS. The key secondary end point was overall survival (OS). Other secondary end points included overall response rate (ORR) and safety. Biomarker analysis was an exploratory end point.
At the time of the second interim analysis, the median duration of follow-up was 26.4months. Median PFS was 25.3months 95% confidence interval (CI) 23.0–30.3 for ribociclib plus letrozole and 16.0months (95% CI 13.4–18.2) for placebo plus letrozole (hazard ratio 0.568; 95% CI 0.457–0.704; log-rank P=9.63×10−8). Ribociclib treatment benefit was maintained irrespective of PIK3CA or TP53 mutation status, total Rb, Ki67, or p16 protein expression, and CDKN2A, CCND1, or ESR1 mRNA levels. Ribociclib benefit was more pronounced in patients with wild-type versus altered receptor tyrosine kinase genes. OS data remain immature, with 116 deaths observed; 50 in the ribociclib arm and 66 in the placebo arm (hazard ratio 0.746; 95% CI 0.517–1.078). The ORR was 42.5% versus 28.7% for all patients treated with ribociclib plus letrozole versus placebo plus letrozole, respectively, and 54.5% versus 38.8%, respectively, for patients with measurable disease. Safety results, after a further 11.1months of follow-up, were comparable with those reported at the first analysis, with no new or unexpected toxicities observed, and no evidence of cumulative toxicity.
The improved efficacy outcomes and manageable tolerability observed with first-line ribociclib plus letrozole are maintained with longer follow-up, relative to letrozole monotherapy.
NCT01958021
Enlightened by the Caputo fractional derivative, the present study deals with a novel mathematical model of generalized thermoelasticity to investigate the transient phenomena due to the influence of ...a non-Gaussian pulsed laser type heat source in a stress free isothermal half-space in the context of Lord–Shulman (LS), dual-phase lag (DPL), and three-phase lag (TPL) theories of thermoelasticity simultaneously. The memory-dependent derivative is defined in an integral form of a common derivative on a slipping interval by incorporating the memory-dependent heat transfer. Employing Laplace transform as a tool, the problem has been transformed to the space-domain, and it is then solved analytically. To get back all the thermophysical quantities as a function of real time, we use two Laplace inversion formulas, viz. Fourier series expansion technique (Honig in J Comput Appl Math10(1):113–132,
1984
) and Zakian method (Electron Lett 6(21):677–679,
1970
). According to the graphical representations corresponding to the numerical results, a comparison among LS, DPL, and TPL model has been studied in the presence and absence of a memory effect simultaneously. Moreover, the effects of a laser pulse have been studied in all the thermophysical quantities for different kernels (randomly chosen) and different delay times. Then, the results are depicted graphically. Finally, a comparison of results, deriving from the two numerical inversion formulas, has been made.
Oxy-coal combustion is the most promising technology for the reduction of greenhouse gases from pulverized coal-fired power plants. Oxy-coal combustion employs recirculated flue gas mainly consisting ...of CO
2
and water vapor as a diluent. Thus, the pulverized coal particles are surrounded and burned under steam rich atmosphere. The addition of H
2
O would have a significant impact on the combustion characteristics of oxy-coal combustion. The chemical and physical properties of steam are different than the CO
2
, replacement of CO
2
with steam will alter heat capacity, gasification, and radiation properties considerably. The present article numerically compares ideal dry recycle oxy-coal combustion (0% H
2
O) with wet recycle oxy-coal (10-50% H
2
O) and oxy-steam combustion (H
2
O replaces whole CO
2
from oxidant) in terms of flow field, temperature distribution, oxidizer distribution, radiative heat transfer, char consumption, and species concentration. Higher flame temperatures under enriched steam oxy-coal combustion cases were found due to lower volume heat capacity of H
2
O than CO
2
. Steam enrichment also enhanced char gasification reaction, which has affected temperature distribution and incident radiation profile inside the combustion chamber. Peak temperature obtained under oxy-steam case is around 10% higher than ideal dry recycle case (0% H
2
O) and 2-5% higher than the wet oxy-coal combustion cases having 50-10% H
2
O in the oxidizer.
In the present article, CFD simulation of various oxy-fuel combustion cases has been performed to find out the influences of oxy-fuel combustion environment on temperature distribution, char ...consumption, radiative properties and temporal variation of particle phase variables such as particle temperature, volatile and char mass fraction. The oxy-fuel combustion cases are obtained by varying O
2
and CO
2
concentrations while keeping the total volume flow rate constant. Four oxy-fuel cases are considered in the present work having oxygen concentration 21%, 25%, 30%, and 35%. The present article also investigates the influence of char gasification reactions on temperature distribution, species concentration and temporal profile of particle char mass fraction. The predicted temperature distribution and radiative properties under oxy-fuel cases are compared with the corresponding values obtained under air-fired combustion as for retrofit existing power plants comparable values are desirable. The oxy-30 case having 30% oxygen has almost identical temperature and radiative profiles. With an increase in oxygen concentration in oxy-fuel cases leads to an increased peak temperature and surface incident radiation due to the rise in local stoichiometry, which results in enhanced reaction kinetics and burning rate. The peak temperature obtained in oxy-25, oxy-30 and oxy-35 cases is around 10%, 18%, and 24% higher than the oxy-21 case. Reduced char burnout time is obtained due to the presence of gasification reactions.
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