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In this work, electrically conductive thermoplastic elastomeric blend composite films based on polystyrene (PS)/ethylene‐co‐methyl acrylate (EMA) filled with functionalized graphene were developed via the solution mixing technique. Morphological analysis revealed that selective localization of amine‐functionalized reduced graphene oxide (G‐ODA) sheets in the EMA phase of co‐continuous binary blend formed a well‐connected dense conductive pathway by graphene sheets ultimately facilitating the double percolation phenomenon. The electrical percolation threshold was achieved at ~2 wt% of G‐ODA loading which was much lower than that for both single polymer composites. An electrical conductivity of 0.9 S/cm was obtained for blend composite film with 10 wt% of graphene concentration whereas for the same filler loading, PS and EMA composites exhibited electrical conductivity of 1.9 × 10−1 and 2.3 × 10−1 S/cm, respectively. The obtained thermal conductivity of the blend composite with 10 wt% of G‐ODA loading was 0.95 W/m K with 400% enhancement compared to the neat blend system. The same composite exhibited increased real and imaginary permittivity of 92 and 83, respectively. The electrical percolation threshold is well‐correlated with the percolation concentration found from storage modulus and thermal conductivity data. The fabricated PS/EMA blend composite film exhibited absorption‐dominant electromagnetic interference SE of −25 and − 35 dB in X‐band frequency (8.2–12.4 GHz) for 10 wt% of graphene loading with a sample thickness of 0.5 and 1 mm, respectively. [ABSTRACT FROM AUTHOR]

Over the past few years, thermoplastic nanocomposites reinforced with different types of nanofillers have seen widespread use in the automotive, pharmaceutical, food packaging and electronic sectors. Among the different nanofillers used to fabricate thermoplastic composite–based packaging materials, nanoclay and graphene are very beneficial for producing high‐barrier packaging materials. The high aspect ratio and large surface area of both nanoclay and graphene facilitate uniform filler dispersion and tortuous path in the thermoplastic matrix, which ultimately improves the physico‐mechanical, thermal and barrier to oxygen, water vapour and light as well as antimicrobial properties, which are key requirements for packaging materials. Because graphene nanomaterials are electrically and thermally conductive, these thermoplastic nanocomposites may display excellent electrical‐, thermal‐ and microwave‐shielding capabilities, allowing them to be used in electronic packaging. This review aims to summarize the preparation and characterization of thermoplastic nanocomposites based on different types of nanoclay, graphene and graphene derivatives, as well as their prospective applications in food and electronic packaging. This review paper also discusses the factors that can affect the performance and attributes of these packaging materials, such as processing conditions, types of nanofillers, functionalization or modification of nanofillers for better filler dispersion and so forth. This paper presents a comprehensive and state‐of‐the‐art article on nanoclay‐ and graphene‐loaded thermoplastic nanocomposite–based packaging materials. [ABSTRACT FROM AUTHOR]

Hexafluoroisopropanol (HFIP) stands out as a versatile solvent in synthetic chemists' repertoire, facilitating a diverse array of intricate chemical reactions. It demonstrates a multifaceted role that extends beyond conventional uses and, in many cases, the mechanism appears to be complicated. This feature article elucidates the significance of HFIP in the context of Lewis and Brønsted acid‐catalyzed reactions with a specific emphasis on the regio‐ and stereoselective functionalization of unsaturated carbon‐carbon bonds. [ABSTRACT FROM AUTHOR]

Ionic liquid is increasingly being used as a chemical modulator of multi‐walled carbon nanotubes (MWCNT). Here, we report the practical method for producing biodegradable electromagnetic interference (EMI) shield films made of thermoplastic polyurethane (TPU), polybutylene adipate‐co‐terephthalate (PBAT), and 1‐(2‐aminoethyl)‐3‐methyl‐1H‐imidazol‐3‐ium modified MWCNT (MIL). The field emission scanning electron microscopy study of cryo‐fractured 50:50 PBAT/TPU blend giving co‐continuous morphology and subsequent polymer EMI shield nanocomposite material had shown the co‐continuous nanofiller distribution. The nanoparticles were chosen to be distributed in the PBAT portion, according to subsequent research employing HRTEM and DMA. The electrical percolation threshold (EPT) is determined to be situated within 1–3 wt% of nanoparticles loading as the remarkable shift in total EMI shielding efficiency from −14.6 dB (for 1 wt%) to −28.6 dB (for 3 wt%) of nanoparticle‐loaded film at 10 GHz (in X‐band region) for a 0.8 mm thick film reveals that the EPT is approximately at 2 wt% of nanoparticle loading. The effective EMI shielding of −37.3 dB was achieved by 10 wt% of MIL loading. [ABSTRACT FROM AUTHOR]

Multifunctional polymer/graphene based lightweight and flexible nanocomposite films are increasingly being utilized in the packaging, electronics, and pharmaceutical industries together. Herein, two graphene derivatives: silver nanoparticle decorated reduced graphene oxide (G‐Ag) and chemically reduced graphene oxide (rGO) prepared by wet chemical method and graphene nanoplatelets (GNP) have been incorporated into linear low density polyethylene (LLDPE) thermoplastic matrix via melt compounding method. The incorporation of graphene derivatives affected the physico‐mechanical, electrical and thermal conductivity, and barrier properties (both oxygen and water vapor permeability) of the nanocomposite films. With 5 wt% of G‐Ag, rGO, and GNP loading, the thermal conductivity of these three nanocomposite films was enhanced by an average of 136.7%, 123%, and 143.3%, respectively. Graphene having high specific surface area and aspect ratio allow for a tortuous passage of oxygen and water molecules through the nanocomposite film, ultimately improving both oxygen and water vapor impermeability qualities for all LG‐Ag, LrGO, and LGNP nanocomposites. Moreover, the films have been tested against both gram‐positive and gram‐negative bacteria to ensure their bactericidal activity. The prepared composite films also showed Electromagnetic Interference (EMI) shielding effectiveness (−21, −17, and −19 dB) higher than the commercial cut‐offs. The thermoplastic nanocomposite films with promising thermal conductivity might be an excellent choice for bacteria‐resistant and barrier‐capable packaging and efficient thermal management EMI shields in electronics. [ABSTRACT FROM AUTHOR]

To investigate the potential effect of the pyrolytic carbon black (CBp) and pyrolytic heavy oil (HO), we incorporated them into styrene‐butadiene rubber (SBR) as reinforcing filler and plasticizing agent, respectively. Since the industrial N330 CB's specific surface area and other specifications adhere to the CBp standard, it has been selected as a benchmark. To test HO's applicability, conventional (AO) was substituted with it. We experimented with the N330 and CBp in the 1/1 variant. We examined the impacts on the cure behavior, physical characteristics such as density and hardness, mechanical properties, abrasion resistance, dynamic mechanical performance, and thermal properties of the filled SBR composites. According to field emission (FESEM) and transmission electron microscopy (TEM) micrographs, the increased tensile and tear strength is due to N330 black's superior dispersion over CBp in the rubber matrix. Better dispersion in N330 type CB is also justified by lower tan δmax from the dynamic mechanical analysis (DMA) study. Utilizing HO changes the curing conditions since it comprises more sulfur, which accelerates the formation of sulfur–sulfur cross‐links. Increased tensile and tear strengths, as well as improved dispersion in the rubber matrix, have been seen with the combined use of N330 and CBp. Meanwhile, HO could function well in place of commercially available AOs. Highlights: The impact of scrap tires on human health and the environment is explored.Recovered carbon black (CB) from waste tire mixed with styrene‐butadiene rubber in various ratios.Pyrolytic oil is also incorporated to check its reusability in tire formulation.Similar cure characteristics and mechanical strength were found in the composites.Replacement of the conventional CB is proposed with recovered black. [ABSTRACT FROM AUTHOR]

Flexible and electrically conductive polymer nanocomposite materials are gaining popularity as EMI shield materials. Herein, we report the successful fabrication of Thermoplastic polyurethane (TPU)/polybutylene adipate‐co‐terephthalate (PBAT)/dodecyl amine modified multi‐walled carbon nanotubes (MWCNT)‐based biodegradable polymer nanocomposite films employing solvent mixing and casting technique. The FESEM analysis of the cryofractured TPU/PBAT blend (containing 50 wt% of both the polymers) is found to be perfectly co‐continuous. Field emission scanning electron microscopy (FESEM), High‐resolution transmission electron microscopy (HRTEM) analysis followed by a selective dissolution test of polymer nanocomposites revealed that MAm nanofillers are mostly confined to the PBAT phase. The electrical percolation threshold is found to be between 3 and 5 wt% of dodecyl amine modified MWCNT loading as the electrical conductivity and EMI shielding efficiency are found to be shifting from 10−4 to 0.827 S/cm and −29.4 and −36 dB respectively as the nanofiller loading is increased from 3 to 5 wt% keeping the thickness of the polymer nanocomposite films constant at 0.8 mm. [ABSTRACT FROM AUTHOR]

Event cameras are bio‐inspired sensors that offer advantages over traditional cameras. They operate asynchronously, sampling the scene at microsecond resolution and producing a stream of brightness changes. This unconventional output has sparked novel computer vision methods to unlock the camera's potential. Here, the problem of event‐based stereo 3D reconstruction for SLAM is considered. Most event‐based stereo methods attempt to exploit the high temporal resolution of the camera and the simultaneity of events across cameras to establish matches and estimate depth. By contrast, this work investigates how to estimate depth without explicit data association by fusing disparity space images (DSIs) originated in efficient monocular methods. Fusion theory is developed and applied to design multi‐camera 3D reconstruction algorithms that produce state‐of‐the‐art results, as confirmed by comparisons with four baseline methods and tests on a variety of available datasets. [ABSTRACT FROM AUTHOR]

Interference of electromagnetic (EM) radiation generated from different electronic gadgets produces noises diminishing their performance. So, shielding of EM interferences (EMI) is necessary to achieve noise‐free performance from electronic gadgets. In the present work, we have produced thermoplastic polyurethane (TPU)/polybutylene adipate‐co‐terephthalate (PBAT) based biodegradable binary polymeric blend and incorporated different carbonic nanofillers such as Vulcan XC‐72 conductive carbon black (VCB) and multiwalled carbon nanotube (MWCNT) into it employing solvent mixing and casting technique and studied the morphology of polymer blends, EMI shielding effectiveness in X‐band of the EM spectrum as well as mechanical performance, electrical performance, and biodegradability of polymer nanocomposites. The selective nanofiller distribution in the low viscous PBAT phase of the "co‐continuous" binary blend is found to achieve a "lower electrical percolation threshold" compared to neat polymer nanocomposites. For each of the TPU/PBAT/VCB and TPU/PBAT/MWCNT nanocomposites, electrical percolation threshold of around 12.5 and 5 wt% respectively has been achieved successfully. Nanocomposite sheets with a thickness of 1.0 mm and loading of 30 wt% of VCB and 15 wt% of MWCNT gave EMI shielding values of −25 dB and −28 dB respectively at a frequency of 8.4 GHz. [ABSTRACT FROM AUTHOR]

A common form of Corporate Social Responsibility (CSR) by firms is to agree to donate a fixed portion of private good revenues to a charitable cause. In this paper, we explore a new rationale for such CSR known commonly as Cause‐Related Marketing (CRM). We argue that linking private good purchase with charitable donations to a partnering nongovernmental organization (NGO) allows the firm to price discriminate between altruistic consumers who wish to make charitable donations out of their income and nonaltruistic consumers who do not place any value on such donations. The disparity in altruistic propensities translates into a difference in private good value which limits the firm's ability to extract consumer surplus in the private good market. Linking private good sales to charity brings down the variation in private good value and enables the firm to appropriate greater surplus. At the same time, by inducing nonaltruistic consumers to donate through their purchase of the charity‐linked good, CRM may also increase charitable donations to the NGO beyond the level that would be achieved under the standard voluntary contributions equilibrium. We extend our model to consider the effects of CRM on profits and donations when altruistic consumers can choose between donating directly to the NGO out of their income and donating through their purchase of the charity‐linked good. We consider this choice in the context of CRM advertising where firms make the altruism of their consumers public and thus provide exhibition value to donations made through the charity‐linked good. We find that the case for CRM strengthens when we allow the firm to appropriate exhibition utility through advertising while enabling greater donations for the NGO through direct donations as well as CRM. [ABSTRACT FROM AUTHOR]

In recent years, synergistic dual catalysis has been in the spotlight as a robust strategy for carbon−carbon and carbon−heteroatom bond formation. This review highlights the unique strategies of dual catalysis achieved in the past two decades, involving Pd‐catalyst combined with various first‐ and second‐row transition metals (like Cr, Fe, Cu, Ru, etc.), Lewis acids (based on Yb, Mg, Ti, Al, etc.) or organocatalysts (like squaramide, CPA, and NHC) to achieve valuable heterocyclic cores. Heterocycles find wide applications in pharmaceutical and agrochemical industries. Several organocatalysts like chiral phosphoric acid, NHC, squaramide, etc. and metal salts work in synergy with palladium to provide high‐value products taking advantage of the vast development in cross‐coupling reactions. This review is a comprehensive collection of such dual‐catalysis strategies. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed cascade cyclization received much attention in organic synthesis due to its efficiency and rapid transformation of simple starting materials into complex molecular skeletons. Celebrating the 10th year of the prestigious Nobel prize for palladium chemistry, we witness it still proceeds strong over other transition metals for its versatility. Cascade reactions in contemporary organic synthesis reduced cost and time through careful design. It has emerged as the first choice, a powerful tool for multiple bond formations in one step with a wide range of functional group tolerance due to the deep understanding of various pathways. A variety of compounds with biological relevance with complex molecular scaffolds have been achieved using these cascade coupling reactions. This review outlines Pd‐catalyzed cascade reactions from the post‐Nobel era. Nevertheless, more discoveries and endless possibilities for new transformations are underway. [ABSTRACT FROM AUTHOR]

Harmful electromagnetic radiations that are generated from different electronic devices could be absorbed by a light weight and mechanically flexible good electromagnetic interference (EMI) shielding polymer nanocomposite. On the other hand, different electronic wastes ("e‐wastes") which are generally polymer building materials generated from wastes of dysfunctional electronic devices are not naturally biodegradable. Our recent effort has been employed to produce bio‐degradable EMI shielding polymer nanocomposite. For that purpose, we had prepared a 50:50 ratio polylactic acid/thermoplastic polyurethane polymer nanocomposite by mixing the conducting carbon black with the blend following the facile and industrially feasible solution mixing method. Morphological characterizations by scanning electron microscopy and transmission electron microscopy analysis revealed the co‐continuous morphology of the neat blend as well as polymer nanocomposites with the preferential distribution of conductive filler on a particular polymer phase. The polymer nanocomposites gave good mechanically with improved thermal properties. We got EMI shielding effectiveness around −27 dB with a low percolation threshold at around 30 wt% filler loading in the polymer nanocomposite at the X‐band frequency domain (8.2–12.4 GHz). Later we had studied the biodegradability of the PLA/TPU along with their composites (TXPXCX) by employing the respirometry method and got a satisfactory result to ensure their biodegradability. [ABSTRACT FROM AUTHOR]

Insertion of 2:1 organo‐modified phyllosilicate tactoids into rheologically tough thermoplastics has extraordinary potential candidate in oxygen permeability and microstructural toughening. Herein, two commercially abundant clays have been taken for improvement of the thermoplastic's gas barrier property in reasonably low loading. The cause of low loading has been accounted to the usage of maleated polyethylene (MA‐g‐PE) during the melt mixing tenure. The optimized nanocomposite compression molded film has been tested against uniaxial stretching, which showed a negligible change in the residual permanent set with sacrificing the elongation at break feature. Moreover, nanoindentation was also performed to get the hardness of the sample surface. The flow behavior of the nanocomposites showed thixotropic likely with increasing the frequency. Oxygen transmission rate (OTR) has significantly decreased for tallow amine‐modified nanoclay system (cloisite 15A) in comparison to cloisite Na+ providing 'tortoise path' formation inside the matrix. Thus, hitherto, the work could demonstrate and provide the information of comparative studies between organo‐clay and simple phyllosilicates, which could be remediation of the loopholes in mechanical toughening and gas barrier lineaments. [ABSTRACT FROM AUTHOR]

Asparagine‐linked glycosylation 13 homolog (ALG13) encodes a nonredundant, highly conserved, X‐linked uridine diphosphate (UDP)‐N‐acetylglucosaminyltransferase required for the synthesis of lipid linked oligosaccharide precursor and proper N‐linked glycosylation. De novo variants in ALG13 underlie a form of early infantile epileptic encephalopathy known as EIEE36, but given its essential role in glycosylation, it is also considered a congenital disorder of glycosylation (CDG), ALG13‐CDG. Twenty‐four previously reported ALG13‐CDG cases had de novo variants, but surprisingly, unlike most forms of CDG, ALG13‐CDG did not show the anticipated glycosylation defects, typically detected by altered transferrin glycosylation. Structural homology modeling of two recurrent de novo variants, p.A81T and p.N107S, suggests both are likely to impact the function of ALG13. Using a corresponding ALG13‐deficient yeast strain, we show that expressing yeast ALG13 with either of the highly conserved hotspot variants rescues the observed growth defect, but not its glycosylation abnormality. We present molecular and clinical data on 29 previously unreported individuals with de novo variants in ALG13. This more than doubles the number of known cases. A key finding is that a vast majority of the individuals presents with West syndrome, a feature shared with other CDG types. Among these, the initial epileptic spasms best responded to adrenocorticotropic hormone or prednisolone, while clobazam and felbamate showed promise for continued epilepsy treatment. A ketogenic diet seems to play an important role in the treatment of these individuals. [ABSTRACT FROM AUTHOR]

Transient self‐assembling systems often suffer from accumulation of chemical wastes that interfere with the formation of pristine self‐assembled products in subsequent cycles. Herein, we report the transient crystallization of a cucurbit[8]uril‐based host‐guest complex, preventing the accumulation of chemical wastes. Base‐catalyzed thermal decarboxylation of trichloroacetic acid that chemically fuels the crystallization process dissolves the crystals, and produces volatile chemical wastes that are spontaneously removed from the solution. With such self‐clearance process, no significant damping in the formation of the crystals was observed. The morphology and structural integrity of the crystals was also maintained in subsequent cycles. The concept may be further extended to obtain other temporally functional materials, quasicrystals, etc. based on stimuli‐responsive guest molecules. [ABSTRACT FROM AUTHOR]

We extend promotion signaling theory to generate new testable implications concerning racial differences in promotions. In our model, promotions signal worker ability. When tasks differ substantially across job levels, the opportunity cost of not promoting qualified non‐whites/non‐Asians is large, so employers are less likely to inefficiently withhold their promotions. Thus, given prepromotion performance, the extent to which non‐whites/non‐Asians have lower promotion probabilities decreases when tasks vary more across levels. Racial differences in wage increases at promotion diminish when tasks vary more across levels. Evidence from a single firm's personnel records supports the model's predictions concerning promotion probabilities. [ABSTRACT FROM AUTHOR]

This study proposes a novel technique of speed estimation for permanent magnet direct current (PMDC) brushed motor. The impact of armature teeth-slots and commutation of PMDC motor on armature current is considered in this study to estimate the speed. In many applications, speed measurement of motors is essentially required. Conventionally mechanical sensors are coupled to the motor shaft for speed measurement. Recently many sensorless methods for speed estimation of motor had been introduced. This study proposes a new method where the variation in effective magnetic path reluctance due to continuous alternation in teeth-slots positions with respect to stationery poles is considered. Combined effects of effective magnetic path reluctance variation and armature commutation cause ripple in armature current. In this study, the effect of teeth-slots in armature current is investigated using finite-element approach and also it is verified experimentally. Furthermore, an elementary circuitry is included in this study in support of the proposed method from armature current. The performed test on a 24 V-100 W brushed PMDC motor indicates that the proposed method is effective in wide range of speed estimation considering the effect of change in mechanical load or terminal voltage level. [ABSTRACT FROM AUTHOR]

Noncompete covenants or covenant not to compete ( CNC) are clauses in employment contracts in which the employee agrees not to gain employment with a competitor firm. In this article, we study the efficiency aspects of such contracts by incorporating the effect of labor mobility restrictions on knowledge transfer across firms, investment decisions by firms, and investment by workers. Following research that shows state-wise variations in the degree of CNC enforcement, we allow the strength of CNC enforcement to vary as a matter of regulatory policy and derive the optimal strength of enforcement. We also look at how regulations around CNCs should be optimally designed when employers can use collusive agreements, such as 'no poaching' agreements, as an alternative to noncompete clauses. Given recent allegations of employer collusion among large Silicon Valley firms, we argue for a cautious approach in designing policies on CNC enforcement. ( JEL J24, J41, J63, K31) [ABSTRACT FROM AUTHOR]

This study proposes an incentive-based femtocell cooperation scheme for indoor macrocell users (MUs) in an underlay two-tier heterogeneous network which helps the indoor MUs to achieve higher data rate through time sharing access from the femtocell. Due to underlay spectrum sharing nature of the femtocell, the network suffers from severe cross-tier interference. To manage this cross-tier interference, a price-based power control scheme is also proposed for the femtocell access point (FAP) whereby the macrocell base station (MBS) controls the transmit power of the FAP by pricing their resulted cross-tier interference power level subject to a maximum tolerable interference limit. A Stackelberg game has been formulated and analysed for joint pricing-based power control and incentive-based cooperation game. Numerical results show the performance of the proposed scheme in terms of achievable rate of indoor users and utilities of both the MBS and the FAP for different locations of the femtocells. [ABSTRACT FROM AUTHOR]

This article develops a theory concerning the choice between standard promotion practices and up-or-out contracts. Our theory is based on asymmetric learning and promotion incentives. We find that firms employ up-or-out contracts when firm-specific human capital is low and standard promotion practices when it is high. We also find that, if commitment to a wage floor is feasible and effort provision is important, up-or-out is employed when low- and high-level jobs are similar. These results are consistent with many of the settings in which up-or-out is typically observed, such as law firms and academia. [ABSTRACT FROM AUTHOR]

We extend the model of voluntary contributions to multiple public goods by allowing for bundling of the public goods. Specifically, we study the case where agents contribute into a common pool which is then allocated toward the financing of two pure public goods. We explore the welfare implications of allowing for such bundling vis-à-vis a separate contributions scheme. We show that for high income inequality or for identical preferences among agents bundling leads to higher joint welfare. Interestingly, a welfare improvement can in some cases occur despite a decrease in total contributions. On the contrary, when agents are heterogenous, for low income inequality bundling can lead to lower total contributions and may decrease welfare compared to a separate contribution scheme. Our findings have implications for the design of charitable institutions and international aid agencies. [ABSTRACT FROM AUTHOR]

The article discusses studies on use of physicochemical processes for treatment of aqueous streams like domestic and industrial wastewaters, drinking water, contaminated groundwater, and mentions information on processes used like microfiltration and ultrafiltration.

In this paper, we study supplier-firm interactions to explain firms' outsourcing relationships. We show that in an imperfect information setup a firm learns about the quality of its suppliers through repeated interaction. As the firm determines the suppliers' quality with greater precision, it gives a greater proportion of its contracts to these ‘better’ suppliers. We report evidence from African manufacturing firms that is consistent with our hypothesis: both frequency and volume of transactions increase with the length of a firm's relationship with its supplier. These effects are stronger in poor contracting environments. [ABSTRACT FROM AUTHOR]

A direct regioselective C2 amidation of pyrroles and indoles with pyrimidone and quinazolinone derivatives is developed. [ABSTRACT FROM AUTHOR]

The total synthesis of actinophenanthroline A, a marine actinomycete within the family of Streptomycetaceae (strain CNQ-149) is reported. [ABSTRACT FROM AUTHOR]

The title compounds are prepared by mild and green deep eutectic solvent mediated cyclization of substituted or unsubstituted anthranilamides with a wide range of aliphatic, aromatic, and heteroaromatic aldehydes in good to excellent yields. [ABSTRACT FROM AUTHOR]

The presence of electron-withdrawing groups on the chloroquinoline-3-carbaldehyde moiety provides inseparable mixtures of the corresponding products in low yields. [ABSTRACT FROM AUTHOR]

26 examples [ABSTRACT FROM AUTHOR]