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Herein, we report a simple solid state synthetic route to prepare carbon-Fe based magnetic nanoparticles with different compositions and morphologies through annealing of amorphous Fe nanoparticles under appropriate conditions. Tri-n-octylphosphine (TOP) capped amorphous Fe nanoparticles with a mean diameter of 3.2 nm were synthesized using solvated metal atom dispersion (SMAD) method. Annealing of as-prepared Fe nanoparticles at 300 °C produced carbon encapsulated crystalline bcc-Fe nanoparticles, whereas at higher temperatures i.e., 400 °C and 500 °C, spherical Fe 3 C/C core-shell nanoparticles were obtained. Annealing of as-prepared Fe nanoparticles in the presence of tri-n-octylphosphine oxide (TOPO) ligand under optimized conditions yielded rod shaped Fe 3 C/C core-shell morphology. The size, composition and particle morphology of these magnetic nanoparticles could be controlled by changing the reaction time, temperature and the concentration of the TOPO ligand. Magnetic measurements show that rod shaped Fe 3 C nanoparticles exhibit enhanced coercivity (Hc) values compared with spherical Fe 3 C nanoparticles, which is due to shape anisotropy. © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Research Summary: A firm's stakeholder orientation toward its employees is argued to be beneficial for firm outcomes. However, this orientation may also have disparate impacts on particular behaviors and outcomes, such as local versus distant search, which impose contradictory firm requirements. We find that while a strong firm–employee relationship leads to increasingly higher levels of local search (exploitation), it also leads to increasingly lower levels of distant search (exploration). In additional supplementary analyses, we find similar disparate effects on the productivity of innovation and its market value, as well as a moderating effect of the firm's relationship with other stakeholders which exacerbates both the positive and negative impacts of firm–employee relationships. We discuss the implications of these findings for both the innovation and the instrumental stakeholder literatures. Managerial Summary: Motivating employees toward generating new ideas and innovations is an important challenge for most firms. Establishing the firm as a trustful and good partner for employees may engender in them the commitment and willingness to invest in such activities. However, questions remain as to how “well” the firm should “treat” its employees, and the potential adverse consequences from over‐investing in such relationships. This paper examines these important practical questions and finds that establishing strong relationships with employees can be simultaneously beneficial and harmful for the firm depending on the type of new ideas it seeks. We find that such strong relationships helps with motivating employees to build on and perfect existing knowledge, but is harmful with respect to bringing in new and unfamiliar knowledge.

Metal nanosponges of silver, gold, palladium, platinum, and copper have been prepared via simple reduction of their salts using ammonia borane or substituted amine boranes. This synthetic method involves metal salt reduction using amine borane which forms nanoparticles in the absence of capping agent in high dielectric solvent; these colloidal particles attach together to form three dimensional porous metal nanosponges. Hydrogen storage properties of these metal nanosponges were investigated by measuring pressure-composition isotherms. Furthermore, the catalytic activities of these metal nanosponges were tested for 4-nitrophenol reduction which showed better catalytic activity as compared to their bulk state. Among all the metal nanosponges, palladium showed highest catalytic activity which was found to be recyclable over several cycles and the porous structure remained intact after catalysis. Herein, improvement in the catalytic activity and hydrogen storage characteristics of porous metals with respect to their bulk analogues further signifies the importance of nanoporous structures.

Co-digestive ripening is a versatile strategy for the preparation of binary metal nanoparticles such as core-shell, composites, and alloys. The mechanism of co-digestive ripening is hypothesized to involve inter-atom transfer facilitated by capping agents. In this work, co-digestive ripening of a metal (Au) and a semiconductor (CdS) system has been presented. This process involves co-refluxing of a physical mixture of Au and CdS colloids in presence of hexadecyl amine (HDA) in mesitylene solvent. Individual colloids of Au and CdS were prepared by solvated metal atom dispersion (SMAD) method. The growth control of nanoparticles using HDA resulted in the formation of monodisperse particles via a room temperature digestive ripening process. Au/CdS nanocomposite obtained via co-digestive ripening strategy was characterized by a matrix-like structure made up of CdS nanoparticles in which Au nanoparticles were embedded. CdS nanoparticles were found to establish an intimate surface contact with Au nanoparticles and the matrix of CdS surrounding Au was developed via aggregation during co-refluxing. Formation of the Au/CdS nanocomposite is proposed to involve a ligand replacement process wherein HDA molecules capping the Au surface are displaced by CdS owing to strong Au-CdS interaction. The Au/CdS composite thus obtained showed superior photocatalytic activity compared to pure CdS nanoparticles for dye degradation reaction.

Identifying crystal structure sensitivity of a catalyst for a particular reaction is an important issue in heterogeneous catalysis. In this context, the activity of different phases of ruthenium catalysts for benzene hydrogenation has not yet been investigated. The synthesis of hcp and fcc phases of ruthenium nanosponges by chemical reduction method has been described. Reduction of ruthenium chloride using ammonia borane (AB) and tert-butylamine borane (TBAB) as reducing agents gave ruthenium nanosponge in its hcp phase. On the other hand, reduction using sodium borohydride (SB) afforded ruthenium nanosponge in its fcc phase. The as prepared hcp ruthenium nanosponge was found to be catalytically more active compared to the as prepared fcc ruthenium nanosponge for hydrogenation of benzene. The hcp ruthenium nanosponge was found to be thermally stable and recyclable over several cycles. This self-supported hcp ruthenium nanosponge shows excellent catalytic activity towards hydrogenation of various substituted benzenes. Moreover, the ruthenium nanosponge catalyst was found to bring about selective hydrogenation of aromatic cores of phenols and aryl ethers to the respective alicyclic products without hydrogenolysis of the C-O bond.

Designing and developing ideal catalyst paves the way to green chemistry. The fields of catalysis and nanoscience have been inextricably linked to each other for a long time. Thanks to the recent advances in characterization techniques, the old technology has been revisited with a new scope. The last decade has witnessed a flood of research activity in the field of nanocatalysis, with most of the studies focusing on the effect of size on catalytic properties. This led to the development of much greener catalysts with higher activity, selectivity and greater ease of separation from the reaction medium. This Minireview describes the emerging trends in the field of nanocatalysis with implications towards green chemistry and sustainability.

The development of new synthetic strategies to obtain mono-disperse metal nanoparticles on large scales is an attractive prospect in the context of sustainability. Recently, amine-boranes, the classical Lewis acid-base adducts, have been employed as reducing agents for the synthesis of metal nanoparticles. They offer several advantages over the traditional reducing agents like the borohydrides; for example, a much better control of the rate of reduction and, hence, the particle size distribution of metal nanoparticles; diversity in their reducing abilities by varying the substituents on the nitrogen atom; and solubility in various protic and aprotic solvents. Amine-boranes have not only been used successfully as reducing agents in solution but also in solventless conditions, in which along with the reduction of the metal precursor, they undergo in situ transformation to afford the stabilizing agent for the generated metal nanoparticles, thereby bringing about atom economy as well. The use of amine boranes for the synthesis of metal nanoparticles has experienced an explosive growth in a very short period of time. In this Minireview, recent progress on the use of amine boranes for the synthesis of metal nanoparticles, with a focus towards the development of pathways for sustainability, is discussed.

A series of new tricyclic pyrrolo[3,2-e]tetrazolo[1,5-c]pyrimidines 8a-l were synthesized and characterized by IR, NMR (1 H and 13 C), and mass spectral analysis. The newly synthesized compounds 8a-l were inspected for their in vitro antitubercular activity against Mycobacterium tuberculosis (MTB) H37 Ra using an established XTT reduction menadione assay (XRMA). The title compounds exhibited minimum inhibitory concentrations (MIC90 ) ranging from 0.09 to >30 μg/mL. Five compounds (8c, 8i-l) were further confirmed for their dose-dependent effect against MTB. These compounds were evaluated in the THP-1 infection model, where 8i (MIC90 = 0.35 μg/mL), 8j (MIC90 = 1.17 μg/mL), 8k (MIC90 = 2.38 μg/mL), and 8l (MIC90 = 1.17 μg/mL) demonstrated significant antitubercular activity. All the ex vivo active compounds showed insignificant cytotoxicity against the human cancer cell lines, HeLa, MCF-7, and THP-1. Inactivity of all these compounds against Gram positive and Gram negative bacteria indicates their specificity. Molecular docking studies in the active site of the sterol 14alpha-demethylase (CYP51) enzyme revealed a similar binding mode to the native ligand in the crystal structure, thereby helping to understand the ligand-protein interactions and to establish a structural basis for inhibition of MTB. The results suggest novel pharmacophores as selective and specific inhibitors against MTB that can be explored further to synthesize lead compounds against tuberculosis. In summary, the results clearly indicate the identification of some novel, selective, and specific inhibitors against MTB that can be explored further for potential antitubercular drugs.

In this work, we compare different precursor approaches for the mild decomposition to copper–aluminum and –gallium powder materials in nonaqueous solution. Referring to previous work on the preparation of Cu–Al alloy materials from [(AlCp*)4] and [CpCu(PMe3)], the amine-stabilized metal trihydrides [(Me3N)AlH3] and [(quinuclidine)GaH3] were used as alternative sources for Al and Ga. In a comparative study, [(Me3N)AlH3] and [(AlCp*)4] were treated with the Cu precursors [CpCu(PMe3)] and [{Cu(mesityl)}5] in mesitylene solution in various molar ratios at 150 °C and 3 bar H2 to give metallic precipitates of the composition Cu1–xAlx (x = 0.67, 0.50, 0.31). Whereas the combination [(AlCp*)4] with [{Cu(mesityl)}5] did not yield an intermetallic phase, all other Cu/Al precursor combinations led to alloyed Cu–Al materials. For x = 0.67, the θ-CuAl2 phase formed, as shown by X-ray powder diffraction (XRD) and solid-state magic-angle-spinning (MAS)NMR spectroscopic studies. Similarly, the reaction of [{Cu(mesityl)}5] with [(quinuclidine)GaH3] immediately led to the precipitation of a gray powder, without the addition of hydrogen. The powder was identified by means of XRD as θ-CuGa2. At x = 0.50 and below, the reactions were less phase selective depending on the precursor combination. [CpCu(PMe3)] combined with both Al precursors afforded a mixture of several Cu–Al phases, whereas [{Cu(mesityl)}5] was treated with [(Me3N)AlH3] to yield a material whose X-ray signature was assigned to the monoclinic Cu0.51Al0.49 phase. The γ-Cu9Al4 phase could not be obtained from [CpCu(PMe3)]; instead, solid solutions of α-Cu were obtained. The treatment of [{Cu(mesityl)}5] with [(Me3N)AlH3] in the Cu/Al molar ratio of 9:4 (x = 0.31) gave a gray powder, which could be identified by XRD as γ-Cu9Al4.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Alliance networks are strategic decisions involving trade-offs between two stylized structural design choices: prominent and entrepreneurial. Prominent alliance networks emphasize benefits arising out of multiple access and affiliation to other prominent firms in the network. An entrepreneurial position, on the other hand, emphasizes brokerage and diversity benefits arising out of access to nonredundant and diverse information. We demonstrate that the performance benefits of each type of alliance network are contingent on environmental change and strategy, and are thus time dependent. Following an environmental change event in the steel industry, alliance networks that were more entrepreneurial performed better, while those that were more prominent suffered performance decline. However, when the change was radical, both types of alliance networks were negatively related to performance. We suggest that following a radical change, industry alliance networks may not have the requisite information necessary for quick and effective strategic responses. Firms pursuing an analyzer strategy performed better when emphasizing a prominent, and to a lesser extent, entrepreneurial alliance network. However, firms that develop an alliance network high on both prominent and entrepreneurial structural positions had lower relative performance. Our results indicate the need for managers to assess their alliance portfolio over time and redesign it based on environmental and strategic contingencies. Copyright © 2008 John Wiley & Sons, Ltd.

New dicationic dihydrogen complexes of the type trans- $[M(\eta ^2-H_2)(PF_3)(diphosphane)_2]^2+ [M = Ru, diphosphane = dppm (Ph_2PCH_2PPh_2); M = Fe, Ru, diphosphane = dppe (Ph_2PCH_2CH_2PPh_2)]$ have been prepared from the precursor hydrides trans- $[M(H)(PF_3)(diphosphane)_2]^+ $ upon reaction with HOTf. In the case of dppm, in addition to the trans-dihydrogen complex ci \varsigma-$[Ru(\eta^2-H_2)(PF_3)(dppm)_2]^2+ $was also obtained in the protonation reaction. The intact nature of the H-H bond in these derivatives has been established using the spin-lattice relaxation time measurements (short$ T_1$ values) and the large $J_H_,_D$ coupling constant of the H-D isotopomers. The H-H bond lengths and the stabilities of the dihydrogen complexes are discussed in terms of the \pi acidity of the $PF_3$ ligand and compared with other systems possessing trans CO and CNH ligands. The trans-$[Ru(\eta^2-H_2)(PF_3)(dppe)_2]^2+ $ complex was found to be remarkably stable with respect to the loss of bound H$_2$ for a period of about 16 h. The H-D isotopomer of this complex exhibits small temperature variations in the J$_H_,_D$ coupling constant. The X-ray crystal structure of trans-$[Ru(H)(PF_3)(dppm)_2][BF_4]$ has been determined

Defining social capital in terms of the information benefits available to a firm due to its strategic alliances we present a theory of social capital that conceptualizes it as a multidimensional construct. We draw from the literature to argue that social capital yields three distinctly different kinds of information benefits in the form of information volume, information diversity, and information richness. This extends current theoretical and empirical research by specifying and empirically demonstrating three interrelated yet distinct dimensions of social capital. Firms vary in their levels of social capital not just on their structural position in an alliance network but also in the dynamics that underlie alliance formation and maintenance. More importantly, the different dimensions of social capital theoretically provide differential benefits. We establish the construct validity of our proposed three-dimensional conceptualization of social capital using longitudinal data on the population of strategic alliances formed during the period 1980–94 by firms in the global steel industry. In addition, we establish predictive validity by demonstrating that the information dimensions have differential effects on firm performance, using firm nationality as a contingency. Copyright © 2002 John Wiley & Sons, Ltd.

A series of new dicationic dihydrogen complexes of ruthenium of the type $trans-[(dppe)_2Ru(\eta^2-H_2)(RCN)][BF_4]_2$ $[dppe = Ph_2PCH_2CH_2PPh_2; R = CH_3, CH_3CH_2, CH_3CH_2CH_2, CH_2=CH, p-CH_3-C_6H_4-CH_2, C_6H_5, and (CH_3)_2N]$ have been prepared by the protonation reaction of the precursor hydrides, trans- $[(dppe)_2Ru(H)(RCN)][BF_4]$ using $HBF_4·OEt_2$. The variable temperature spin-lattice relaxation times $(T_1, ms)$ and the H, D coupling constants of the $\eta^2$ -HD isotopomers indicate the intact nature of the H-H bond in these complexes. It was found that the spectroscopic and chemical properties of these derivatives are not very sensitive to the change in the trans nitrile ligand. The $pK_a$ values of the dihydrogen complexes have been determined using the equilibrium: trans- $[(dppe)_2Ru(H)(RCN)][BF_4] + HBF_4\cdot OEt_2 \rightleftharpoons trans- [(dppe)_2Ru(\eta^2-H_2)(RCN)][BF_4]_2 + Et_2O$ by $^1H\hspace{2mm}NMR$ spectroscopy.

Interfirm relationship networks are strategic resources that can potentially be shaped by managerial action. As a first step towards understanding how managers can shape networks, we develop a framework which explains how industry networks evolve over time and in response to specific events. Our main thesis is that industry events may be either structure-reinforcing or structure-loosening, and that their potential structural impact may be predicted in advance. We validate our hypotheses with longitudinal data on the strategic alliance network in the global steel industry.

An efficiently and environmentally friendly protocol for the synthesis of azlactone derivatives (III) (19 examples) via NH4VO3-catalyzed condensation of hippuric acid (I) with carbonyl compounds (II) is developed.

Samples of gall bladder bile from patients with and without carcinoma of the gallbladder were examined for lipid peroxidation (free radical oxidation) products. 4-hydroxynonenal (HNE) was found in higher concentration in the bile of patients with carcinoma of the gall bladder. There was also a highly significant difference in the concentration of HNE among carcinoma of the gall bladder, cholelithiasis and control group of patients with miscellaneous abdominal disorders. This is the first study of lipid peroxidation in carcinoma of the gall bladder. © 1994 Wiley-Liss, Inc.

Some new 4,5-diphenyl-1H-imidazole derivatives were synthesized in good yields by treating various tetrazolo[1,5-a]quinolines with benzil and ammonium acetate in glacial acetic acid.

Co-Co(2)B and Ni-Ni(3)B nanocomposites were synthesized by the reduction of Co(2+) and Ni(2+) ions using ammonia-borane in methanol. The Co-Ni-B nanocomposite was synthesized by the co-reduction of Co(2+) and Ni(2+) ions. The catalytic activities of these metal nanocomposites were studied for the dehydrogenation of ammonia-borane in methanol. Three moles of H(2) were liberated in 2.5 min and 4.2 min in case of Co-Co(2)B and Ni-Ni(3)B nanocomposites, respectively (catalyst/AB = 0.2). The Co-Ni-B nanocomposite showed greater activity compared to individual metal-metal boride nanocomposites: 3 moles of H(2) were liberated in 1.5 min (catalyst/AB = 0.2). The catalysts were highly recyclable and the activities remained almost unchanged even after several cycles.

Copper nanoparticles have been prepared by the solvated metal atom dispersion (SMAD) method. Oxidation of the SMAD prepared copper colloids resulted in Cu@Cu2O core shell structures (7.7 ± 1.8 nm) or Cu2O nanoparticles depending on the reaction conditions. The nano Cu, Cu@Cu2O core shell, and Cu2O particles were found to be catalytically active for the generation of hydrogen from ammonia–borane either viahydrolysis or methanolysis reaction.

A rapid, solvent-free and environmentally friendly Knoevenagel condensation reaction of 4-oxo-(4H)-1-bcnzopyran-3-carbaldehyde 1 with Meldrum's acid 2 has been carried out under microwave irradiation. The structures of condensed products 3a-g have been characterized on the basis of IR and 1 H NMR spectral data.

The condensation reaction of 4-oxo-4H-1-benzopyran-3-carbaldehyde with 3-methyl-1-phenylpyrazolin-5-(4H)-one has been carried out under ultrasonic irradiation at room temperature (R.T.) in distilled water (D/W) as solvent, catalyzed by borate zirconia catalyst.