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Here the selective and reversible capture of molecular I2 (aqueous as well as in the vapor phase) within the flexible two-dimensional (2D) Cd-MOF [constructed from (1,3,5-tri(1H-benzo[d]imidazol-1-...

In the present work, a one-dimensional metal-organic framework, {[Zn3(TBIB)2(Cl)6]11H2O}n (1), has been synthesized under high temperature and acidic conditions by utilizing the tripodal ligand 1,...

This study aims to assess the microscopic characteristics of Jatropha, Karanja, and Waste cooking oil-based biodiesels vis-a-vis conventional diesel under different ambient conditions in order to understand the in-cylinder processes, while using biodiesels produced from different feedstocks in the compression ignition engines. All test-fuels were injected in ambient atmosphere using a common-rail direct injection (CRDI) fuel injection system at a fuel injection pressure (FIP) of 40 MPa. Microscopic spray characteristics were measured using phase Doppler interferometer (PDI) in the axial direction of the spray at a distance of 60–90 mm downstream of the nozzle and at 0 to 3-mm distance from the central axis in the radial direction. All biodiesels exhibited relatively larger Sauter mean diameter (SMD) of the spray droplets and higher droplet velocities compared to baseline mineral diesel, possibly due to relatively higher fuel viscosity and surface tension of biodiesels. It was also observed that SMD of the spray droplets decreased with increasing distance in the radial and axial directions and the same trend was observed for all test-fuels.

In the last couple of decades, blending of oxygenated additives with gasoline has been advocated to reduce dependence on fossil fuels and to reduce hazardous health effects of gaseous emissions and particulate matter (PM) emitted by internal combustion (IC) engines in the transport sector worldwide. The primary objective of this research was to carry out a comparative analysis of exhaust PM emitted by gasohol (gasoline blended with 10% ethanol, v/v)-fulled spark ignition (SI) engine with that of baseline gasoline-fuelled SI engine. To assess the PM toxicity, physical, chemical and biological characterizations of PM were carried out using the state-of-the-art instruments and techniques. Measurements of regulated and unregulated gaseous species were also carried out at part/full loads. The results showed that the gasohol-fuelled engine emitted relatively lower concentrations of unregulated gaseous species such as sulfur dioxide (SO2), isocyanic acid (HNCO), etc. Physical characterization of exhaust particles revealed that the gasohol-fuelled engine emitted a significantly lower number of particles compared to the gasoline-fuelled engine. The presence of harmful polycyclic aromatic hydrocarbons (PAHs) and higher trace metal concentrations in PM emitted from the gasoline-fuelled engine was another important finding of this study. Biological characterizations showed that PM emitted from the gasohol-fuelled engine were less cytotoxic and had lower reactive oxygen species (ROS) generation potential. Mutagenicity of PM emitted from the gasohol-fuelled engine was also lower compared to that from the gasoline-fuelled engine. Overall, this study demonstrated that utilization of gasohol in SI engines led to the reduction in emissions, and lowering of PM toxicity, in addition to partial replacement of fossil fuels with renewable fuels.

A two-dimensional, tetragonal porous metal organic framework {[Zn2(TBIB)2(HTCPB)2]·9DMF·19H2O}n (1) has been synthesized under hydrothermal conditions by employing 1,3,5-tri(1H-benzo[d]imidazol-1-y...

In the present study, comparison of performance, combustion and emission characteristics of a single cylinder compression ignition (CI) genset engine fueled by biodiesels derived from Waste cooking oil (WCO), Jatropha and Karanja oils vis-a-vis baseline mineral diesel has been carried out. Performance and combustion investigations were carried out at constant engine speed (1500 rpm) and six engine loads (0–100%). WCO biodiesel showed slightly higher heat release rate (HRR) than baseline mineral diesel, while it was slightly lower for Karanja and Jatropha biodiesels. Hydrocarbons (HC) and oxides of nitrogen (NOX) emissions were lower, while carbon monoxide (CO) emission was relatively higher for biodiesels compared to baseline diesel. Smoke opacity was higher for Karanja and Jatropha biodiesels compared to baseline diesel. WCO biodiesel exhibited comparable smoke opacity with baseline mineral diesel except at full load, where it was relatively lower. Particulates were collected from the engine exhaust on a quartz filter paper using a partial flow dilution tunnel at 50 and 100% engine loads, for trace metal analysis using inductively coupled plasma optical emission spectroscopy (ICP-OES). It was found that trace metals such as Ca, Cu, Fe, K, Mg, Na, Zn and Al showed higher concentrations in particulates from all test fuels, while Ba, Cd, Cr, Mn and Mo showed relatively lower concentrations in the particulates collected.

Biodiesel engines produce several intermediate species, which can potentially harm the human health. The concentration of these species and their health risk potential varies depending on engine technology, fuel, and engine operating condition. In this study, experiments were performed on a large number of engines having different configurations (emissions norms/fuel used), which were operated at part load/full load using B20 (20% v/v biodiesel blended with mineral diesel) and mineral diesel. Experiments included measurement of gaseous emissions, and physical, chemical, and biological characterization of exhaust particulate matter (PM). Chemical characterization of PM was carried out for detecting polycyclic aromatic hydrocarbons (PAH's) and PM bound trace metals. The biological toxicity associated with PM was assessed using human embryonic kidney 293T cells (HEK 293T). The mutagenic potential of the PM was tested at three different concentrations (500, 100, and 50 μg/mL) using two different Salmonella strains, TA98 and TA100, with and without liver S9 metabolic enzyme fraction. PM samples exhibited cytotoxic effect on HEK 293T cells (IC

Despite intensive research carried out on particulates, correlation between engine-out particulate emissions and adverse health effects is not well understood yet. Particulate emissions hold enormous significance for mega-cities like Delhi that have immense traffic diversity. Entire public transportation system involving taxis, three-wheelers, and buses has been switched from conventional liquid fuels to compressed natural gas (CNG) in the Mega-city of Delhi. In this study, the particulate characterization was carried out on variety of engines including three diesel engines complying with Euro-II, Euro-III and Euro-IV emission norms, one Euro-II gasoline engine and one Euro-IV CNG engine. Physical, chemical and biological characterizations of particulates were performed to assess the particulate toxicity. The mutagenic potential of particulate samples was investigated at different concentrations using two different Salmonella strains, TA98 and TA100 in presence and absence of liver S9 metabolic enzyme fraction. Particulates emitted from diesel and gasoline engines showed higher mutagenicity, while those from CNG engine showed negligible mutagenicity compared to other test fuels and engine configurations. Polycyclic aromatic hydrocarbons (PAHs) adsorbed onto CNG engine particulates were also relatively fewer compared to those from equivalent diesel and gasoline engines. Taken together, our findings indicate that CNG is comparatively safer fuel compared to diesel and gasoline and can offer a cleaner transport energy solution for mega-cities with mixed-traffic conditions, especially in developing countries.

A simple synthesis for the integration of different nanoparticles (NPs) including Ag, Au, Pd, Cr and mixed (Cu/Fe), has been demonstrated within the nanopores of a non-activated one dimensional porous coordination polymer (PCP) of Cd(II) due to its high flexible structure. There are two different mechanisms (acid formation (HCl/HNO 3 ) and redox activity of the framework) elucidated by electron paramagnetic resonance (EPR). Presence of –NO 2 groups of the ligand act as anchoring sites for metal ions of metal precursors leading to NPs growth within the PCP explained by FTIR. High resolution transmission electron microscopy (HRTEM) images provided insight of the chemical and physical characteristics of the NPs within the framework. Ag/AgO NPs exhibit excellent antibacterial properties at extremely low concentrations. The polymer shows potential for sequestration and reduction of hexavalent Cr (highly toxic) to elemental, trivalent and tetravalent Cr (non toxic). This framework is also an excellent template for fabrication and dry storage of nanoparticles synthesized by mixed metal precursors. Ferromagnetic properties have been shown by Ag and Au NPs integrated frameworks while Cu/Fe@Cd-PCP behaves as a paramagnet material at room temperature.

In this study, the spray and combustion phenomena of biodiesels were investigated in a constant volume combustion chamber (CVCC). Mineral diesel was used as a baseline fuel and biodiesels derived from waste cooking oil, Karanja oil, and Jatropha oil were utilized to investigate the effect of fuel properties on spray and combustion processes. Experiments were performed at high temperature and pressure conditions in order to simulate the atmospheric environment of a diesel engines. Test fuels were injected at an injection pressure of 80 MPa using a common-rail equipped solenoid injector. Macroscopic evaporation characteristics were analyzed by high-speed shadowgraphy technique under evaporating conditions. The representative droplet size distribution and Sauter mean diameter (SMD) were measured using the Phase Doppler Interferometry (PDI) technique, which was applied to study the spray atomization characteristics of the fuels. The air-fuel equivalence ratio in the spray was calculated using mathematical correlations. The quantitative estimations of soot generation in the spray flames were compared using Hue number analysis. From the shadowgraphy images, the biodiesels showed slower air-fuel mixing characteristics than the baseline diesel due to their inferior volatility. While diesel evaporated abruptly after the fuel injection, the biodiesels showed dense liquid regions in the center of the spray plume. Biodiesels also exhibited larger SMD than the baseline mineral diesel in the fuel spray because of their higher density, viscosity, and surface tension. Despite having poor spray atomization characteristics, the calculated equivalence ratio of biodiesels was lower than that of the baseline diesel. This trend was attributed to the oxygen content of biodiesel. The flame luminosity and visible spray flame duration of biodiesels were lower than those of diesel, while the biodiesel spray flames exhibited lower sooting tendency than the baseline diesel.

Immobilization of the nanoparticles (NPs) in a two dimensional porous coordination polymer (PCP) is currently an emerging field for a number of applications. But still it is a great challenge to fabricate any specified metal NPs in a single network. Herein the synthesis of Au, Pd, Mn, Fe, Cu, Zn, Mg, Li, Fe/Cu, Zn/Mg etc, NPs in a highly flexible PCP of Ni(II); {[Ni3(TBIB)2(BTC)2(H2O)6]·5C2H5OH·9H2O}n [TBIB = 1,3,5-tri(1H-benzo[d]imidazol-1-yl)benzene, H3BTC = 1,3,5-benzenetricarboxylic acid] have been reported. This universal host is able to grow mixed metal NPs from mixed metal precursors. Monodentate carboxylate groups of BTC linker act as anchoring sites for the metal ions of the metal precursors. This is the main driving force to grow NPs within the cavities along with the high flexibility of this polymer at room temperature. Mechanism involves acid formation followed by redox reaction to synthesize metal NPs explained by EPR and FTIR. Paramagnetic properties have been shown by as-synthesized Fe NPs integrated framework at room temperature under applied magnetic field up to 17,500 Oe.

A variety of nanoparticles (NPs) including Ag, Au, Pd, Cr and mixed Cu/Fe have been synthesized in a non-activated (without solvent removal) one dimensional coordination polymer (CP) of Zn(II) via two different mechanisms, acid formation and redox activity of the framework. Main driving force to grow these NPs within the cavities of CP is the presence of free oxygens of one of the monodentate carboxylate groups of BDC ligand. These free oxygens act as anchoring sites for the metal ions of the metal precursors. Chemical and physical characteristics of the NPs within the framework have been evaluated by the high resolution transmission electron microscopic (HRTEM) images. Excluding Ag(0) and Pd(0) other NPs are present as combinations of their elemental as well as oxide forms (Au/Au2O3, Cr/Cr2O3/CrO2 and Cu/Cu2O, Fe/FeO). Synthesized Ag NPs within the framework show remarkable antibacterial efficacy at extremely low concentrations. Ag, Au and Cu/Fe NPs show ferromagnetic properties within the framework at room temperature. This polymer has potential to sequester highly toxic Cr(VI) to non toxic Cr(0), Cr(III) and Cr(IV) species.

Herein, a one step in situ co-synthesis of porous coordination polymers of Ni(II), Co(II) and Mn(II) encapsulating Ag/Ag2O and Au/Au2O3 nanoparticle clusters (spheres and rods) is reported by employing precursors of metal and PCPs, under hydrothermal conditions. No surfactant and reductant have been used. After synthesis of these clusters at high temperature they come out from the cavities of polymers and nucleation process continues inside the cavities. These Ag/Ag2O and Au/Au2O3 nanoclusters encapsulated frameworks show strong paramagnetic and ferromagnetic (soft) properties respectively at room temperature. While electrical characterization data shows that Ag/Ag2O/PCP displays very high conductivity in the range of 1.80×104 S/m which represents the higher end of semiconductance in comparison to Au/Au2O3/PCP which has conductance of 5.9×10−4 S/m representing semiconductivity in the lower mid range at room temperature.

Non corrosive gas, such as CO 2 , is an environment greenhouse pollutant, but at the same time it is a reusable material with a highly attractive application profile and potential as a building block to create added value for the chemical industry. Current technologies for carbon capture are cumbersome, energy intensive and expensive. However, amongst new developments, porous coordination polymers (PCPs) are being viewed as materials with great potential for CO 2 capture. The ability to flexibly design and tune properties of such materials results in different levels of affinity for CO 2 sorption/desorption. Imidazole/benzimidazole and benzoic acid based coordination polymers are of interest from the view point that various architectures such as rigid, flexible, interpenetrating, etc., can be designed to influence cavity pore size and different types of supramolecular interactions existing within the pores. CO 2 sorption, in these structures, not only depends on surface area and void volume but is also influenced by the electronic environment, i.e., functionalization of the pores with either coordinatively unsaturated metal ions or Lewis base groups. In this review, other important influencing factors including strong non-covalent interactions (π-π bonding, anion-π bonding, CH-π bonding, and H-bonding) present on the pore walls, facilitating selective adsorption of CO 2 molecules in substantial quantities (even if Langmuir surface area is very low) are discussed. These interaction potentials in the pores decide quantitatively the sorption of CO 2 as function of temperature and pressure.

A systematic investigation of silver/silver chloride (Ag/AgCl) and gold (Au) nanoparticle (NP) formation within non-activated isostructural porous coordination polymers (PCPs) namely Ni-PCP, Co-PCP and Mn-PCP at room temperature is reported without the use of any reducing agent and deterioration of host frameworks. A supercharged environment due to the presence of free anions make these PCPs suitable templates for the growth of nanoparticles (NPs) in high yields. High resolution transmission electron microscopy (HRTEM) images provided insight into the size, shape and distribution of the NPs within the frameworks. Different shapes and sizes of the NPs are attributed to the differences in the levels of supramolecular interactions within these isostructural series and the ionic radii which is related to the charge density of metal nodes. From an electron paramagnetic resonance (EPR) study it is evidenced that synthesis of Au NPs in Ni-PCP is completely through redox reaction via strong charge transfer between coordinated metal and the metal precursor, and the others are via acid formation through anions present in the cavities of PCPs. Au NPs integrated frameworks display different soft ferromagnetic properties when placed in a magnetic field at room temperature.

Diesel engine emissions consist of several harmful gaseous species, some of which are regulated by stringent emission norms, while many others are not. These unregulated emission species are responsible for adverse environmental impact and serious health hazards upon prolonged exposure. In this study, a four-cylinder, 1.4 l, compression ignition (CI) engine was used for characterization of unregulated gaseous exhaust emissions measured at 2500 rpm at varying engine loads (0, 25, 50, 75 and 100%). The test fuels investigated were Karanja biodiesel blended with diesel (KB5, KB20), methanol blended with diesel (M5) and baseline mineral diesel. Fourier transform infrared (FTIR) emission analyzer was used to measure unregulated emission species and raw exhaust gas emission analyzer was used to measure regulated emission species in exhaust. Results show an increasing trend for some of the unregulated species from blends of biodiesel such as formaldehyde, acetaldehyde, ethanol, n-butane however methane reduced upon using these oxygenated fuel blends except methanol, compared to baseline mineral diesel. Nevertheless, no significant changes were observed for sulfur dioxide, iso-butane, n-octane, n-pentane, formic acid, benzene, acetylene and ethylene upon using biodiesel and methanol blends.

In this study, spark ignition of hydrogen enriched natural gas (HCNG), a fast emerging alternative gaseous fuel, was experimentally investigated in a suitably modified single cylinder spark ignition (SI) engine. Port fuel injection of the HCNG engine using a high volume flow rate solenoid injector, controlled by a customized injector control unit and electronic control unit (ECU) was done and the fuel injection timings and duration were controlled for each load. Fuels with different H/C ratios in the final HCNG mixture were investigated for their engine performance, emissions and combustion characteristics. Engine investigations were carried out at constant engine speed of 1500 rpm for different H/C ratios (4, 4.22, 4.5, 4.85, 5.33 and ∞). Spark timing was kept constant (32° bTDC) for all test blends. Relative air–fuel ratio (RAFR) was kept constant for all loads during the experiments in order to avoid misfire at lower engine load. Hydrogen exhibited higher pressure peak (Pmax) but lower maximum brake torque (MBT) compared to other test fuels due to lower knocking limit. Brake thermal efficiency (BTE) was superior for test fuel with H/C: 4.5. NOx emissions were higher for test fuel with H/C: 4.22 and relatively lower for hydrogen compared to baseline natural gas.

Ag, Au and Cu NPs have been encapsulated within as-synthesized 2D flexible porous coordination polymer {[Zn(TBIB)(HTCPB)]∙2DMF·H2O}n [TBIB = 1,3,5-tri(1H-benzo[d]imidazol-1-yl)benzene, H3TCPB = 1,3,5-Tris(4′-carboxyphenyl-)benzene] 1 at room temperature without employing any reducing agent. Presence of monodentate carboxylate along with the non-coordinated carboxylic acid groups (−COOH) are the main driving forces towards the synthesis of NPs from the polymer. Ag and Cu NPs synthesis takes place through acid formation (HNO3/HCl) while Au NPs have been synthesized by the redox activity of the polymer, elucidated by the electron paramagnetic resonance (EPR). Chemical and physical characteristics of the NPs have been provided by HRTEM. The coordination polymer not only synthesizes the NPs but also prevents them from agglomeration acting as a protective membrane to store fabricated NPs. Magnetic measurements show that all of the NPs integrated polymers reveal ferromagnetic properties at room temperature.

A two-fold interpenetrated, three dimensional Zn-based porous MOF, {[Zn(BPBA)Cl]⋅5H2O}n (1) [BPBA = 3,5-bis-(4-oxo-4H-pyridin-1-yl)-benzoate], has been synthesized at high temperature under solvothermal conditions by the in situ acidic hydrolysis of the tripodal ligand 3,5-bis-(4-oxo-4H-pyridin-1-yl)-benzonitrile (BPBN). The de-solvated MOF exhibited selective CO2 adsorption at a temperature of 195 K and 1 bar pressure over N2 and H2. Interestingly, the four coordinated Zn(II) sites in the MOF exhibited high Lewis acidic heterogeneous catalytic activity for the synthesis of naphthimidazole in excellent yield without pre-activation of the MOF. The Zn(II) sites could directly coordinate to the substrate to catalyze the chemical transformation by an expansion of the coordination number. The π-π supramolecular interactions between the aromatic rings of the framework and the substrate molecule might help in the substrate activation.

Increasing level of CO2 in the atmosphere is a serious concern. Converting CO2 waste to a potentially clean fuel methanol, by catalytic hydrogenation, will be highly demanding in the perspective of economy and sustainability. Traditionally, it is produced from syngas at high temperature and pressure by utilizing catalyst (Cu/ZnO/Al2O3). For methanol synthesis, cheap CO2 sources are available at industrial scale through CCS technology but options for low-cost hydrogen are limited. Despite it Cu nanoparticles in the catalyst are initially discrete and well dispersed but slowly they aggregate and separate out from the ZnOx interface diminishing the catalytic activity over time ascribed to less number of active sites. To maintain high catalytic activity and selectivity of this catalyst, its stabilization is very crucial. This problem can be resolved by metal–organic frameworks (MOFs) consisting of pores which anchor Cu/ZnOx nanoparticles in their channels preventing their aggregation as well as their phase separation between Cu and ZnOx interface. Due to strong metal-supported interactions and confinement effects within the MOF lead to more dispersed and ultrasmall nanoparticles for CO2 hydrogenation.

Carbon dioxide, i.e. CO2, is the most important greenhouse gas and considered to contribute significantly to climate change and global warming. Besides the reduction of CO2 emissions, there is also a high potential to integrate CO2 in terms of a carbon conversion cycle to products using it as the carbon source. This book deals with the effects of CO2 on climate change and global warming and with the whole process chain from CO2 separation, purification and conversion to chemicals and fuels. CO2 which is a final product can also be considered as an initial material for product formation like chemicals and fuels like in nature where CO2 is used from the atmosphere to produce with water and sunlight sugar and oxygen by photosynthesis.

Direct injection spark ignition or gasoline direct injection (GDI) engines are superior in terms of relatively higher thermal efficiency and power output compared to multipoint port fuel injection engines and direct injection diesel engines. In this study, a 500 cc single cylinder GDI engine was used for experiments. Three gasohol blends (15% (v/v) ethanol/methanol/butanol with 85% (v/v) gasoline) were chosen for this experimental study and were characterized to determine their important fuel properties. For particulate investigations, exhaust particles were collected on a quartz filter paper using a partial flow dilution tunnel. Comparative investigations for particulate mass emissions, trace metal concentrations, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) analyses, and high-resolution transmission electron microscopy (HR-TEM) imaging of the particulate samples collected from different test fuels at different engine loads were performed. For majority of the experimental conditions, gasohols showed relatively lower trace metal concentration in particulates compared to gasoline. HR-TEM images showed that higher engine loads and presence of oxygen in the test fuels increased the soot reactivity. Multicore shells like structures were visible in the HR-TEM images due to growth of nuclei, and rapid soot formation due to relatively higher temperature and pressure environment of the engine combustion chamber. Researches world-over are trying to reduce particulate emissions from GDI engines; however there is a vast research gap for such investigations related to gasohol fueled GDI engines. This paper critically assesses and highlights comparative morphological characteristics of gasohol fueled GDI engine.

In this experimental study, spray and combustion characteristics of a single cylinder optical engine were evaluated by varying the fuel injection pressure (FIP) (40, 80, and 120 MPa). Karanja, Jatropha, and waste cooking oil (WCO) biodiesels were the test fuels and their results were compared with baseline mineral diesel. There was no significant difference observed in the spray tip penetration amongst all test fuels, however the spray cone angles of biodiesels were slightly higher than baseline mineral diesel. Mineral diesel showed relatively shorter injection delay compared to biodiesels at 40 and 80 MPa FIP. Jatropha and Karanja biodiesels showed higher flame luminosity at all FIPs, while WCO biodiesel showed lower flame luminosity, especially at higher FIPs of 80 and 120 MPa, primarily due to lower viscosity of WCO biodiesel. Flame spatial fluctuation (FSF) and flame nonhomogeneity (FNH) were also found to be higher for biodiesels at lower FIP of 40 MPa. Karanja and Jatropha biodiesels showed higher FSF and FNH at higher FIPs compared to WCO biodiesel.

A novel two dimensional (2D) porous coordination polymer {[Ni3(TBIB)2(BTC)2(H2O)6]·5C2H5OH·9H2O}n (1) [TBIB = 1,3,5-tri(1H-benzo[d]imidazol-1-yl)benzene, H3BTC = 1,3,5-benzenetricarboxylic acid] has been synthesized solvothermally. In 1, layers are stacked in ABAB⋯ fashion by virtue of strong intermolecular hydrogen bonding interactions, to generate an overall 3D supramolecular framework consisting of isolated pockets accommodated solvent molecules inside. These lattice-constituent solvent molecules are replaced by dichloromethane (DCM), after immersing complex 1 in DCM for seven days at room temperature, yielding {[Ni3(TBIB)2(BTC)2(H2O)6]·6CH2Cl2·6H2O}n (2). Arrangement of layers is slightly changed in compound 2 wherein, small pockets are completely absent. Characterization of these two compounds 1 and 2 has been performed employing, single crystal X-ray diffraction, IR spectroscopy, thermogravimetry and elemental analysis. Importantly, complex 1 shows selective sorption of CO2 gas at low temperature and pressure, and simultaneously displays high heterogeneous catalytic activity for Knoevenagel condensation at high temperature.

Two one dimensional coordination polymers of Cd(II) and Zn(II), {[Cd(NPBI)(BDC)(H2O)]·2H2O}n (1) and {[Zn(NPBI)(BDC)]·H2O}n (2), [NPBI = 1,1′-(4-nitro-1,3-phenylene)bis(1H-benzo[d]imidazole), BDC = 1,3-benzenedicarboxylate] have been synthesized under solvothermal conditions. Both compounds have been characterized by single X-ray crystallography, IR spectroscopy, TGA and elemental analysis. These one dimensional (1D) structures are further stacked to three dimensional (3D) supramolecular framework through polar packing which arises through intensive hydrogen bonding interactions giving rise to 1D dumbbell shaped small cavities which accommodate lattice water molecules. After removal of solvent molecules, permanent porosity in complex 1 with 13.6% void volume was verified by CO2 sorption isotherm that shows selective CO2 gas uptake at low temperature (195 K) as well as at ambient temperature conditions (273 K and 298 K). Topological analysis shows that coordination polymer 1 possesses uninodal 4-connected SP1-periodic net with point symbol {33.42.5} and compound 2 assumes 3-connected SP1-periodic net with point symbol {42.6}.

Proton conductivity is shown for a previously reported, porous coordination polymer {[Mn 2 (DBIBA) 3 ]·(NO 3 )·3DMF·4H 2 O} n , [DBIBAH = 3,5-di(1H-benzo[ d ]imidazol-1-yl)benzoic acid] consisting of hexagonal cavities. Nitrate ions and water molecules are present in the central part of the cavity forming a well defined one dimensional extended hydrogen-bonding network. This framework was revealed to be a proton conductor by temperature dependent study at 100% relative humidity (RH). The proton conductivity was 1.64 × 10 − 4 S·cm − 1 , 2.36 × 10 − 4 S·cm − 1 and 3.09 × 10 − 4 S·cm − 1 at 30%, 50% and 70% RH respectively.

Through in situ basic hydrolysis of cyanide functional group of 3-(1H-benzo[d]imidazol-1-yl)-5-(1H-imidazol-1-yl)benzonitrile a new three dimensional porous coordination polymer {[Co2(BIIBA)3]·(NO3)·5H2O}n (1) (BIIBA = 3-(1H-benzo[d]imidazol-1-yl)-5-(1H-imidazol-1-yl)benzoate) have been isolated under hydrothermal conditions and characterized by single crystal X-ray diffraction. Topological analysis of 1 revealed a (3,3,4,5)-connected 4-nodal unprecedented pkb8 net with point symbol {4.62}2{42.66.82}{63}{65.8}.

By using the tripodal ligand 1,3,5-tri(1H-benzo[d]imidazol-1-yl)benzene (TBIB) and the carboxylate donor ligand 1,3,5-benzenetricarboxylic acid (H 3 BTC), two new coordination polymers, {[Cd 3 (TBIB) 4 (BTC) 2 ]·2C 2 H 5 OH·11H 2 O} n ( 1 ) and {[Zn(TBIB)(HBTC)]·3H 2 O} n ( 2 ), have been obtained under solvothermal conditions. Characterization has been done through X-ray crystallography, IR spectroscopy, thermogravimetry and elemental analysis. Complex 1 displays a novel three dimensional (3D) (3,3,3,3,4,5,5)-connected 7-nodal net with a unique {4.5.6.7 2 .8 3 .9 2 }{4.5.7}{4.5 2 .8 3 }{4.6.7}{4.8 2 } 2 {4 2 .5 2 .8 3 .9 3 } topology while compound 2 reveals a 1D ladder structure which is further extended into a 3D supramolecular architecture through non-covalent hydrogen bonding, C–H⋯π and O–H⋯π interactions, consisting of a 3-connected SP1 -periodic net with the point symbol {4 2 .6}. The metal-free ligand TBIB exhibits strong fluorescence, while this is quenched in both coordination polymers.

Energy is a basic requirement for economic development. Growing energy consumption has resulted in world becoming increasingly dependent on fossil fuels such as coal, oil and gas; therefore, it becomes necessary to develop a sustainable path of energy. Gaseous fuels and biofuels seem to have the potential to contribute significantly to India’s energy security. This monograph shows the current status of different alternative fuels and describes some advanced techniques to improve the quality of alternative fuels. Utilization of these alternative fuels in existing vehicles is another important aspect, which has been covered in this monograph.

A simple synthesis route for growth of Ag/AgO nanoparticles (NPs) in large quantitative yields with narrow size distribution from a functional, non-activated, Ni (II) based highly flexible porous coordination polymer (PCP) as a template has been demonstrated. This template is a stable storage media for the NPs larger than the pore diameters of the PCP. From EPR study it was concluded that NPs were synthesized via two mechanisms i.e. acid formation and the redox activity of the framework. Size range of Ag/AgO NPs is sensitive to choice of solvent and reaction time. Direct use of Ag/AgO@Ni-PCP shows influential growth inhibition towards Escherichia coli and the pathogen Salmonella typhimurium at extremely low concentrations. The pristine template shows no cytotoxic activity, even though it contains Ni nodes in the framework.

A porous coordination polymer {[Mn2(DBIBA)3]NO3·3DMF·4H2O}n (1) [DBIBAH = 3,5-di(1H-benzo[d]imidazol-1-yl)benzoic acid] has been synthesized solvothermally and structurally characterized by single-crystal X-ray diffraction. The following four new coordination polymers {[Mn2(DBIBA)3]·ClO4·DMF·H2O}n (2), {[Mn2(DBIBA)3]·Cl·DMF·8H2O}n (3), {[Mn2(DBIBA)3]·NO3·CH3OH·5H2O}n (4) and {[Mn2(DBIBA)3]·NO3·3CH3COCH3·7H2O}n (5) have been synthesized from 1 via anion/solvent exchange protocols in a single-crystal to single-crystal fashion at room temperature. Gas sorption studies for desolvated compounds 1, 2, and 3 show that CO2 uptake capacity is entirely dependent upon the size of the anion present in the framework. Complex 1 also exhibits antiferromagnetic properties below 17 K, confirmed through magnetic susceptibility measurements.

A series of isostructural compounds, {[Ni2(DBIBA)3]·(BF4)·6H2O}n (1), {[Ni2(DBIBA)3]·(ClO4)·3H2O}n (2), {[Ni2(DBIBA)3]·(NO3)·3H2O}n (3), {[Ni2(DBIBA)3]·Cl·C2H5OH}n (4) {[Co2(DBIBA)3]·(ClO4)·3H2O}n (5), {[Co2(DBIBA)3]·Cl·3C2H5OH}n (7), {[Co2(DBIBA)3]·Cl·3DMF}n (8), {[Co2(DBIBA)3]·Cl·3CH3COCH3·7H2O}n (9), and {[Mn2(DBIBA)3]·Cl·3DMF·3H2O}n (10), have been afforded via anion and solvent exchanges of previously reported coordination polymers {[Ni2(DBIBA)3]·Cl·18H2O}n, {[Co2(DBIBA)3]·Cl·9H2O}n, and {[Mn2(DBIBA)3]·Cl·3H2O}n (DBIBA = 5-di(1H-benzo[d]imidazol-1-yl)benzoate). Anion-exchanged compounds including {[Co2(DBIBA)3]·(NO3)·3H2O}n (6) have also been synthesized under solvothermal conditions by employing metal salts and the corresponding acid hydrolysis of the cyanide functional group of 5-di(1H-benzo[d]imidazol-1-yl) benzonitrile (DBIBN). These structures are obtained with retaining crystallinity, and only insignificant changes are observed in bond lengths and bond angles involving the metal ion. However, n...

The bifurcated ligand 5-di(1H-benzo[d]imidazol-1-yl) benzonitrile (DBIBN) under solvothermal condition, undergoes basic as well as acid hydrolysis to the corresponding carboxylic acid (DBIBA). Four new coordination polymers; {[Cd(DBIBA)(CH3COO)]} n (1), {[Zn(DBIBA)(CH3COO)]⋅H2O} n (2), {[Zn(DBIBA)(OC2H5)]⋅H2O} n (3) and {[Co(DBIBA)(CH3COO)]⋅H2O} n (4) have been synthesized under solvothermal conditions. Compound 1 has a 3D structure with uninodal 4-connected crb/BCT topology with point symbol of {4.65}. In contrast, compounds 2–4 are 2D layered structures having uninodal 3-connected hcb net with a vertex symbol of {63}. The 2D layers are further assembled to an overall 3D supramolecular architecture with strong π–π interactions between layers. Further reinforcement of the 3D assembly occurs due to an array of H-bonding interactions with lattice water molecules present within the layers. All the compounds have been characterized by single X-ray crystallography, IR spectroscopy, TGA, PXRD measurements and elemental analysis. Although the metal-free DBIBN ligand exhibits fluorescence, it is quenched in the coordination polymers.

Sustainable energy source and cleaner environment is the most important requirement for developing countries. In India, total primary energy consumption was ~0.5 BTOE in 2008, which is expected to rise up to ~1.2 BTOE by 2035. In such a scenario, biofuel utilization program seems to be a promising solution because biofuels are relatively cleaner and can be produced from indigenous resources available locally. However availability and continuous supply are the most challenging tasks for the countrywide implementation of biofuels program. In such a scenario, advanced techniques of biofuel production including bio-technology route seem to have significant potential for the energy security in future. This monograph covers practical aspects of biofuel production, utilisation, challenges and limitations and outlines the strengths and constraints of different biofuel production techniques.

Two new isostructural 3D porous coordination polymers {[Ni2(DBIBA)3]·Cl·18H2O}n (1), {[Mn2(DBIBA)3]·Cl·3H2O}n (2) (DBIBA = 5-di(1H-benzo[d]imidazol-1-yl)benzoate) have been synthesized by acidic hydrolysis of cyanide functional group of 5-di(1H-benzo[d]imidazol-1-yl) benzonitrile under solvothermal conditions. Both the compounds have been characterized by X-ray crystallography, IR spectroscopy, thermogravimetry, powder X-ray diffraction, and elemental analysis. They form isoreticular structures with binodal 4,6-connected net having 1D hexagonal channels. These channels are occupied by water molecules. Frameworks are stabilized by hydrogen bonding interactions with anion and π–π interactions in the hexagonal cavity. Desolvated 1 exhibits selective CO2, while 2 shows N2, H2, and CO2 gas adsorption properties without any selectivity. This difference in gas adsorption properties is attributed to different degrees of flexibility of the framework. Magnetic susceptibility measurements at low temperature show wea...

Osteoma is benign neoplasm with slow growth characterized by deposition of compact lamellar cortical or cancellous bone creating a tumour mass. It is still unclear whether osteomas are benign neoplasms or hamartomas. They have typical clinical presentations and are easily diagnosed with the help of radiographs. We present a rare case of non-syndromic multiple osteomas in the craniofacial region which are typically restricted to the midline and presents radiographically as craniofacial fibrous dysplasia causing a diagnostic dilemma.

A simple method for the sequestration of As(III) and Cr(VI) from water has been demonstrated by utilizing a highly flexible porous coordination polymer (PCP) of Ni(II) in its as synthesized form or without solvent removal. This PCP reduces the high toxicity of As(III) and Cr(VI) ions into non-toxic As(0) and Cr/Cr2O3/CrO2 (zero, tri and tetravalent) nanoparticles (NPs) within its pores, and this is characterized by powder x-ray diffraction, x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. The high functionality of this polymer is due to the presence of monodentate carboxylate groups of a benzenetricarboxylate linker, which provide anchoring sites to the metal ions of the metal precursors. Due to the highly oxidising nature of these toxic ions, a redox reaction takes place between the framework metal ions and toxic metal ions, which is explained by an electron paramagnetic resonance study. This is the first report to synthesize non-toxic, as well as useful, NPs of As and Cr from their highly toxic ions within the cavities of a PCP for remediation of the toxic waste stream and contaminated waste water.