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Layer-by-layer (LbL) strategy has been developed to form bulk heterojunction (BHJ) structure for processing efficient organic solar cells (OSCs). Herein, LbL slot-die coating with twin boiling point solvents (TBPS) strategy was developed to fabricate highly efficient OSCs, which matches with large-scale, high throughput roll-to-roll (R2R) industrialized mass process. The TBPS strategy could produce high-quality thin film without any additive, leading to the optimized vertical phase separation with interpenetrating nanostructures, as well as the enhanced charge transport and extraction. Thus, the power conversion efficiency up to 14.42% was achieved for [(2,6-(4,8-bis(5-(2-ethylhexyl-3-fluoro)thiophen-2-yl)-benzo [1,2-b:4,5-b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5′,7′-bis(2-ethylhexyl)benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione)]:2,2′-((2Z,2′Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3″:4″,5″]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene)) bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (PM6:Y6) OSCs fabricated via sequentially LbL slot-die coating using the TBPS strategy under ambient condition. The research provides a potential route for industrialized production of high-efficiency and large-area OSC devices.

With the advancement of micro machining technology, the high-heat-flux removal from miniature electronic devices and components has become an attractive topic. Flow boiling in micro-channels is an optimal form of heat transfer and has been widely employed in high-heat-flux cooling applications. This comprehensively-reviewed article focused on the available recent literatures of experimental investigation regarding the flow boiling heat transfer and unstable behaviors of the fluid with lower boiling point in micro-channels. The thermal-fluid characteristics and potential heat transfer mechanisms of low-boiling-point fluids flow boiling in different narrow passages were summarized and discussed. The literatures regarding the pressure drop and occurrence of the unstable phenomena existing in two-phase flow boiling process were also discussed. The emphasis was given to the heat transfer enhancement methods as well as instability elimination, and various methods such as modification of surface and channel flow geometries were considered. Some future researches in the field of micro-scale flow boiling were suggested.

‘Higher’ alcohols, which contain more than two carbons, have a higher boiling point, higher cetane number, and higher energy density than ethanol. Blends of biodiesel and higher alcohols can be used in internal combustion engines as next-generation biofuels without any modification and are minimally corrosive over extensive use. Producing higher alcohols from biomass involves fermenting and metabolizing amino acids. In this review, we describe the pathways and regulatory mechanisms involved in amino acid bioprocessing to produce higher alcohols and the effects of amino acid supplementation as a nitrogen source for higher alcohol production. We also discuss the most recent approaches to improve higher alcohol production via genetic engineering technologies for three microorganisms: Saccharomyces cerevisiae, Clostridium spp., and Escherichia coli. Proteins are polymers of various amino acids, connected via peptide bonds and classified as a major feedstock for bioenergy production. Higher alcohols are high-density alternative fuels that increase the longevity of transportation fuels. Proteins have a significant role in the fermentation process by providing amino acids for the growth of microorganisms, and enhancement of sugar permeability, in carbohydrate-rich sources. Due to the environmental and economic advantages of recombinant DNA technology, fermentation is the most used process for industrial-scale alcohol production. Applying this technology to higher alcohols can significantly improve industrialization for advanced fuel production. Extraction techniques are used to separate and mitigate the toxicity of alcohols produced in the fermentation broth to maintain the microbial cell viability for longer.

Tungsten sulfide is a promising, though less explored layered transition metal dichalcogenides material which can be exfoliated into mono and fewlayers with enhanced electronic, optoelectronics, sensing and catalytic properties. Liquid-phase exfoliation in high-boiling-point solvents (i.e., N -methyl-2-pyrrolidone), surfactant-assisted exfoliation and polymer-associated exfoliation are some of the widely used techniques for mass exfoliation of layered materials. Due to the high boiling point of these well-established solvents, surfactants and co-solvents, it is difficult to get pristine nanosheets, which are of highest importance in applications like gas sensing. The common solvents like acetone and water have been employed in this work along with low power ultrasonication waves to exfoliate bulk WS 2 which makes this process low cost and convenient. The effect of freezing on exfoliation has been effectively utilized to tailor Hansen solubility parameters of solvents. Monolayers and few layers with lateral dimension of few hundred nanometers have been synthesized with yield of 2.7% and characterized extensively using electron microscopy, atomic force microscopy and optical spectroscopies. The nanosheets have been found to be stable with no precipitation formation for months. This method uses low-boiling-point solvents, hence guaranties the pristine two-dimensional surfaces.

Exploring the graphene material is premised on the graphene sheets being single-layer graphene (SG) or bi-layer graphene (BG) state, and graphene suspension keeps stably disperse are critical. Since graphene has a highly conjugated system, it is easy to conduct strong π-π interaction with conjugated structure. In this paper, by dispersing graphene powder at low boiling point solvent water or ethanol, ensuring the excellent properties of graphene are not affected by the solvent, which simultaneously solves the difficulty of removing organic solvents. On the basis the concentration of graphene suspension can be greatly improved and no damage to the graphene sheets in the presence of dispersant. This method allows us to prepare a large amount of excellent graphene dispersion, making it possible to obtain graphene-based materials through the low-cost technology, as well as opening up the opportunity for exploiting the application of this nanocarbon material with unique structure.

Graphene is a promising additive for lubricants. The rheological properties of graphene nanofluids have a significant impact on the tribological performance of base oil. In this case, rheological properties including viscosity, density, mean square displacement and diffusion coefficient of graphene–PAO nanofluids were investigated by using the nonequilibrium molecular dynamics simulations in order to understand the effects of graphene on the rheological properties of base oil under extreme conditions. The molecular dynamics model was validated according to the experimental and numerical statistics reported by other researchers. The simulation results reflected that the viscosity of base oil was effectively improved by adding graphene nanoparticles. As the concentration of graphene increased, the viscosity of nanofluids becomes higher. However, the diffusion coefficient reached its highest value (3.73 × 10 −9  m 2 /s) with nanofluids containing two pieces of graphene in the system. Furthermore, we found that the graphene played a more significant role in enhancing the viscosity of base oil at high temperature and pressure. The viscosity was especially improved by 290.2% at 0.1 MPa, 500 K. The boiling point of the base oil became higher than 800 K after adding graphene. To our best knowledge, this work is the first study of the rheological properties of graphene–PAO nanofluids using molecular dynamic simulations.

The pyrolysis of polymers is a thermal processing method largely used to convert polymeric waste into valuable products such as oils and carbonaceous residues. The NP-gram method (NP standing for normal paraffins) is useful for the global characterisation of pyrolysis oils with complex composition. Here, we present the fundamental of this method, which is based on the concept of “carbon number”, in conjunction with the boiling point and the chromatographic retention time of chemical compounds. Polypropylene was selected as the model polymer due to its simple mechanism of thermal degradation. The boiling points of the main compounds in polypropylene pyrolysis oil were estimated based on the equations of Egloff and Wiener. A good correspondence was obtained for the estimated boiling points and the position of the compounds in the gas chromatogram. A distinction was made between the number of carbon atoms in the molecule and the corresponding carbon number used in characterisation of pyrolysis oils by NP-gram. Correlation with the chromatographic retention index was also discussed. The application of the NP-gram method for different polymers was also presented.

Vapor–liquid critical properties of mixtures are key parameters in the petrochemical industry and supercritical technology. Experimental measurements and theoretical calculations are the primary methods for determining the critical parameters of mixtures. However, existing empirical correlations to quickly predict the critical temperatures and pressures of mixtures are limited by critical volume data for pure substances. In this work, improved methods of Li method and Kreglewski–Li (KL) method are proposed. Improved methods do not require critical volume data for pure substances, but replace it with acentric factors, normal boiling points, or critical temperatures of pure substances that are easier to obtain and more accurate. About 9,000 critical temperature and critical pressure data points for binary and ternary mixtures were collected to compare and evaluate the Li method, KL method, and improved methods. Notably, the improved methods are only applicable to the class I and II mixtures according to the classification of Van Konynenburg and Scott. Overall, compared with the original method, both Improvement 3 (critical volumes for pure substances of Li method and KL method are replaced with critical temperatures of pure substances) and Improvement 4 (critical volumes for pure substances of Li method and KL method are replaced with normal boiling points of pure substances) greatly improve the accuracy. Meanwhile, when predicting critical temperatures and critical pressures, Improvement 3 not only reduces the input thermophysical property parameters but also improves the prediction accuracy. Among the improved methods, Improvement 4 shows the highest prediction accuracy. The average absolute relative deviation (AARD) and average absolute deviation (AAD) of Improvement 4 for predicting the critical temperatures of binary and ternary mixtures are 1.88%, 7.83 K, 1.60%, and 7.63 K, respectively. The AARD and AAD for predicting the critical temperature of the binary mixtures composed of two pure substances with both acentric factors greater than 0.0955 by Improvement 4 are 1.56% and 7.33 K. The AARD and AAD of Improvement 4 for predicting the critical pressures of binary and ternary mixtures are 4.34%, 0.30 MPa, 3.70%, and 0.19 MPa, respectively. The optimal model selection depends on the specific mixture type under consideration when using improved methods specifically. Graphical abstract

In this study, the effects of six operating conditions on the performance of a 3 kW- ORC (organic Rankine cycle) system were investigated. The results of experiments show that, despite differences in the physical parameters of the three working fluids used, the performance of the ORC system was similar. Further, the cooling water temperature (CWT) was strictly controlled, but the experimental results were affected by the condensation temperature, however the experimental system can maintain stable operation. Since generators are affected by different factors, the variation in generator generation fluctuates over a wide range during steady state operation of the system. The theoretical shaft work of the expander and generator power generation of the system using R245fa exceeds that of the other two working fluids due to the density. It had a maximum generator power conversion efficiency of 64.651% under C1 condition, maximum exergy efficiency of 27.346% under C3 condition; the system has a maximum cycle efficiency of 9.543% and a cold energy utilization efficiency of 5.633%, under C6 conditions; although maximum power generation (1.019 kW) and maximum net work (1.321 kW), the total exergy loss of the system also reached its maximum value (13.756kw) under C5 condition.

In this study, we selected materials that efficiently adsorb total hydrocarbons (THCs) from petrochemical storage facilities and applied four types of activated carbons to adsorb THCs to evaluate their properties. Four gases with low boiling points, namely, ethylene, ethane, propylene, and propane, generated via petrochemical storage facilities, were selected and mixed to a constant concentration with four types of materials and used to investigate the adsorption capacities and desorption properties. The adsorbents comprised two raw materials and two chemically activated materials. The specific surface areas of activated palm (2085 m2/g) and coal (1752 m2/g), which are chemically activated carbons, exhibited a twofold increase compared to those of raw palm (1232 m2/g) and coal (946 m2/g). Thus, we identified the correlations between the physical properties of the activated carbon adsorption materials and their adsorption capacities for four low-boiling-point THCs generated by petrochemical storage facilities.