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A new 2D coordination polymer, namely{[Cd2(BDC)2(bmb)2]·H2O}n (1) (H2BDC = 1,4-benzenedicarboxylic acid and bmb = 1,4-bis(2-methyl-1H-imidazol-1-yl)butane), has been prepared and full characterized. Coordination polymer 1 has 2D layer, which was further extended into 3D supramolecular motif through the π–π packing interactions. Coordination polymer 1 illustrated effectively photocatalytic performance to the disintegration of dyes Rhodamine B (Rh B), methyl orange (MO) and methylene blue (MB). Coordination polymer 1 can remove the dye MB with 90.37% after 100 min under simulated UV light and its catalytic feature conforms to the first order kinetics model. In addition, the possible mechanism of the catalytic degradation toward MB was suggested through the trapping experiments and LC–MS methods.

The intelligent blending of intriguing functionalities in ligands and incorporation of spectroscopically silent metal cations can produce metal-organic frameworks (MOFs) with multifarious applications viz. selective and specific sensing of nitroaromatic compounds (NACs) an important constituent of explosives as well as photocatalytic properties. A new 3D Zn(II)-based metal-organic framework, [Zn4(μ2-OH)2(BDC)3(bip)2] (1) have been synthesized using a mixed ligand strategy using benzene-1,3-dicarboxylic acid (H2BDC) and 1,4-bis(2-methyl-imidazole-yl)-propane (bip) and zinc nitrate via hydrothermal reaction. The framework of 1 adopts a 5-connected 3D network with the Schlafli symbol {33.4.52.62.72}. The luminescent sensing investigation indicated that 1 can behave as a luminescent sensor for highly sensitive detection of nitroaromatics (NACs) especially against 2,4,6-trinitrophenol (TNP). The possible depletion in the photoluminescence intensity of 1 in presence of NACs have been addressed using theoretical calculations which indicated that charge transfer as well as the weak interaction between NACs and MOF may be responsible for the decline in the photoluminescence intensity. The MOF have been used as the photocatalyst for the decomposition of methyl violet (MV). Also, the mechanism for the photocatalysis have been addressed using density of states (DOS) calculations.

Two new d10-configuration based Zn(II) coordination polymers with formula [Zn2(L)2(2,2′-bipy)2]n (1) and [Zn2(L)2(4,4′-bipy)]n (2) (H2L = 4,4′-{[1,2-phenylenebis-(methylene)]bis(oxy)}dibenzoic acid, 2,2′-bipy= 2,2′-bipyridine and 4,4′-bipy= 4,4′-bipyridine) have been synthesized and characterized. Both the compounds had been used as possible luminescent sensors for detecting nitroaromatic compounds (NACs) and as photocatalysts to photodegrade methyl violet (MV) under UV irradiation. The sensing experiments indicated that 2 displayed selective sensing for m-nitrophenol (MNP) with lower limit of detection (LOD) of 1.14 ppm while photocatalytic experiments indicated that 1 displayed better photocatalytic performance than 2 in photodegrading MV.

The linker 1,4-bis(2-methyl-imidazole-yl)-butane (bib) was used to construct two coordination polymers, specifically [Cd(bib)(ipa)]n (1) and [Zn(bib)(tpa)]n (2), in the presence of isophthalic acid (H2ipa) and terephthalic acid (H2tpa), respectively, under solvothermal conditions. Topological analyses reveal that the crystal of complex 1 consists of a 3D threefold interpenetrating network with Schlafli symbol {65.8}, while complex 2 possesses a 2D wavelike layer structure with Schlafli symbol {66}. The photocatalytic properties of both complexes for the degradation of methyl violet have been explored, revealing that complex 2 is a better photocatalyst than 1. A mechanism for the photocatalytic properties of the complexes is proposed, based on the results of density of states (DOS) and partial DOS calculations.

A biocompatible metal-organic framework (MOF) [Zn2(TPL)(FA)(OH)(H2O)] (1) (TPL = theophylline and H2FA = fumaric acid) had been chosen which offers an ideal model for the development of fluorescencent chemosensor using simple synthetic protocol. The MOF 1 have been tested as a fluorescent chemosensor against nitro-aromatics (NACs) and it displayed high selectivity for 4-NT over other NACs as evident by the emission spectroscopy. The alleviation in fluorescence intensity of 1 in presence of different NACs have been explained with the help of theoretical calculations which suggested that there is occurrence of both electron and energy transfer processes, in addition to electrostatic interaction between 1 and NACs which may be responsible for the unprecedented selective alleviation in the fluorescence intensity. Also, 1 had been deployed as a photocatalyst for the degradation of methyl violet (MV) and Rhodamine B (Rh B) in aqueous solution under UV irradiation. The photocatalytic results indicated the 1 exhibit 85% photocatalytic efficiency against Rh B in 100 min, while its efficiency against MV was only 50% under the identical experimental conditions. The possible mechanism for the photocatalytic activity has been proposed using density of states (DOS) calculations.

The articulate combination of intriguing functional groups and luminescence properties can deliver metal-organic frameworks (MOFs) with multifarious applications viz. selective and specific sensing of nitroaromatic compounds (NACs), an important constituent of explosives, as well as sensing of toxic metal ions. In this regard, a new d10 configuration based Zn(ii) metal-organic framework (MOF) {(NH2(CH3)2)[Zn4(ddn)2(COO)(H2O)4]·solvent}n (1) has been synthesized using a π-conjugated and rigid multicarboxylate ligand 3,5-di(3,5-dicarboxylphenyl)nitrobenzene (H4ddn). 1 displays a 3D (3,4,6)-c connected net which is based on two types of binuclear [Zn2(μ2-COO)2(μ1-COO)2] and [Zn2(μ2-COO)4] clusters. Sensing studies of 1 to detect nitro-aromatic compounds reveal highly specific detection of 2,4-dinitophenol (DNP) with remarkable quenching (KSV = 8.93 × 103 M-1) and a low limit of detection (LOD: 1.12 ppm). The luminescence quenching mechanism in the case of 1 in the presence of NACs has been ascribed to the concurrent presence of the charge transfer as well as the weak interaction between the MOF and NACs. The activated framework of 1 also displayed highly selective detection of ferric ions with KSV = 1.13 × 104 M-1 with a low limit of detection (LOD: 1.24 ppm).

The photocatalytic properties of d 10 -based metal-organic frameworks (MOFs) have been developed as a potential technology in the photo-degradation of organic dyes. Herein, a biocompatible metal-organic framework (MOF) {[Zn 2( fer) 2 ]∙0.5H 2 O} n ( 1 ) (fer = ferulic acid) has been selected which shows photocatalytic activity for the degradation of methyl violet (MV) and Rhodamine B (Rh B) in aqueous solution under UV irradiation. The photocatalytic results indicated the 1 exhibit 88% photocatalytic efficiency against Rh B in 100 min, while its against MV was only 54% under the identical experimental conditions. Moreover, a possible mechanism for the photocatalytic activity has proposed by density of states (DOS) calculations.

A porous Zn(II) metal–organic framework (MOF) [Zn(H2L)(4,4′-bipy)0.5]n (1) has been selected and its luminescence sensing for cations and anions as well as the photocatalytic property against methyl violet have been explored. Luminescence studies indicated that 1 could be an efficient multifunctional fluorescent material for highly sensitive detection of metal cation Cu2+ and anions CrO42−. The luminescence intensity of 1 was found to decrease proportionately with increase in the concentration of Cu2+ and CrO42−. Furthermore, the photocatalytic property of 1 for degradation of the methyl violet (MV) have been explored and a possible photocatalytic mechanism have been proposed using density of states (DOS) and partial DOS (pDOS) calculations.

Two metal–organic frameworks, [Co2(L)(H2O)2(4,4′-bipy)]·3CH3CN (1) and [Mn2(L)(1,10-phen)(H2O)]·H2O (2) (H4L = 5-[bis(4-carboxybenzyl)-amino]isophthalic acid; 4,4′-bipy = 4,4′-bipyridine, 1,10-phen = 1,10-phenanthroline), with two different N-donor ligands have been synthesized. The structures of both MOFs were determined using single-crystal X-ray diffraction technique. MOF 1 shows 3D uncommon (4,6,6)-c net with (4.53.62)2(57.66.82)(42.54.66.72.8) topology while in the case of 2, only L4− ligands link Mn(II) ions into a 2D layer structure with chelating 1,10-phen ligand. The results demonstrate that variation in the N-donor ligands plays a pivotal role in deciding the framework of the two MOFs. Both MOFs have been exploited as photocatalyst materials for the degradation of MV. The photocatalysis results indicate that the two MOFs are stable and are prospective candidates for degradation of methyl violet under UV light irradiation. Additionally, 2 displayed superior photocatalytic activity in comparison to 1. The probable photocatalytic activity mechanism for both 1 and 2 against MV has been proposed using density of states (DOS) calculations.

A new Cd(II) based metal–organic framework (MOF), having formula {(CH3)2NH2)6[Cd5(L)4]·H2O·3DMF}n (1), has been synthesized based on a rigid tetracarboxylate ligand of terphenyl-3,3′′,5,5′′-tetracarboxylic acid (H4L). 1 shows a complicated 3D tetranodal 3,3,4,8-c network with uncoordinated –COO− groups. The highly selective luminescent sensing of 2,4-dinitrophenol (2,4-DNP), 2,4,6-trinitrophenol (TNP) and ferric ions was studied for 1 through the alleviation in its fluorescence intensity. The detection limit of 2,4-DNP was found to be 0.84 ppm, which is 20 times higher than that of 1,3,5-trimethylbenzene, demonstrating greater and selective quenching ability. The possible mechanism associated with the decrease in fluorescence intensity of 1 in the presence of nitroaromatics (NACs) has been addressed by theoretical calculations. Furthermore, 1 displays excellent capacity to adsorb methylene blue (MB) with high selectivity, and it maintains an almost identical adsorption performance after being recycled five times.

A new metal–organic framework, formulated as {[Zn2(L)(DMF)3]·2DMF·2H2O} (1), has been synthesized using a symmetrical rigid carboxylate ligand terphenyl-3,3′′,5,5′′-tetracarboxylic acid (H4L). Single-crystal X-ray diffraction analysis shows that 1 possesses a 3D uninodal 4-c lonsdaleite (lon) topology based on binuclear Zn clusters. 1 behaves as a fluorescent chemosensor for highly selective and sensitive detection of Fe3+/Fe2+ ions, 2,4-dinitrophenol (2,4-DNP), p-nitrophenol (PNP) and 2,4,6-trinitrophenol (TNP). Furthermore, the photocatalytic properties of 1 for degradation of methyl violet (MV) and Rhodamine B (RhB) have been explored. The possible emission quenching of 1 in the presence of aromatic compounds has been addressed by theoretical calculations and the photocatalytic activity of 1 against organic dyes has been addressed using density of states (DOS) calculations.

An unexploited pentacarboxylate ligand, 2,5-bis(3′,5′-dicarboxylphenyl)-benzoic acid (H5L), was designed and used for the preparation of metal organic material using Zn2+ as a node. The new compound, {(Me2NH2)[Zn2(L)(H2O)]·0.5DMF}n (1) (DMF = dimethylformamide), has been synthesized and structurally characterized. The topology of the 5-connected anionic framework may be described as (44)(66) (Schlafli symbol) based on {M2(CO2)5} molecular building blocks (MBBs) and L ligands in 1. It has been demonstrated that 1 can act as a fluorescent sensor for highly sensitive detection of nitroaromatics and Fe3+, with a detection limit of 0.54 ppm for 2,4,6-trinitrophenol (TNP) and 0.81 ppm for Fe3+. The possible emission quenching mechanism in the presence of nitroaromatics has been addressed by theoretical calculations.

The hydrothermal reaction of Gd(III) salt with a new rigid dicarboxylate ligand, N,N′‑dioxide‑3,3′‑benzocinnoline dicarboxylic acid (H2L) give rise to a new metal-organic framework (MOF) {[Gd(L)1.5(H2O)2]·2H2O}n (1). The MOF 1 shows 3D microporous framework with 1D parallelogram like channels which are constructed by single rod-shaped {Gd(CO2)2}n chains. The thermal stability, UV/Vis diffuse-reflection spectra, magnetic properties of 1 in the temperature range 2–300 K have been explored. Also its photocatalytic property against the photo-degradation of aromatic dye Rhodamine B (Rh B) has been studied and the plausible photocatalytic mechanism has been addressed using density of states (DOS) calculations.

The reaction of 5-fluorine-3-(3,5-dicarboxylphenxoy)benzoic acid (H3L) with cobalt(II) salt in presence of 1,1'-(1,4-butanediyl)bis (imidazole) (bib) linker yielded two new metal–organic frameworks (MOFs) with compositions [Co4(μ3-OH)2(H2O)2(L)2 (bib)1.5(CH3CN)·3H2O·CH3CN] (1) and [Co8(μ3-OH)4(L)4 (bib)4·8CH3CN] (2). The single crystal X-ray diffraction revealed that 1 exhibited an unusual 3D 3,8-connected framework with 3,8T25 topology based on [Co4(μ3-OH)2] tetranuclear cobalt clusters as secondary building units (SBU) with a (43) (412·54·64·88) Schlafli symbol. In 2, by substituting the CH3CN with neutral N-ligand, a 3D 3,8-connected MOF with 3,10T9 topology and a point symbol of {418.624.83}.{43}2 has been obtained. This represents a highly connected uninodal network topology presently known for flexible carboxylate-based MOF systems. Both the MOFs have been used as photocatalysts for photodegradation of a model organic dye methyl violet (MV). The photocatalytic experiments demonstrated that both 1 and 2 displayed efficient photocatalytic performances to degrade MV under UV irradiation. The plausible mechanism through which both the MOFs displayed photocatalytic properties have been proposed by using band gap calculations.

Two unusual isostructural nanocage-based 3D Ln-MOFs, 1-Ln (Ln = Tb and Eu), were constructed using a new diisophthalate ligand with active Lewis basic triazole sites. 1-Eu exhibits highly efficient luminescent sensing for Fe3+ cations and Cr2O72- anions, and selective CO2 capture over CH4.

A new metal–organic framework having formula {[Cd3(H2O)(L)2][Cd(im)3(H2O)2]·3 H2O} (H4L = 5-bis(4-carbonylbenzyl)aminoisophthalic acid and im = imidazole) (1) has been synthesized. X-ray investigation reveals that 1 is rare 4,4,8-connected (46)(45 · 6)(411 · 615 · 82) topology. The present work indicates that 1 could be a prospective candidate for developing novel luminescence sensors for the selective sensing of nitrobenzene which can be used as a precursor for explosives. Furthermore, the luminescent property of 1 in different solvents analytes as well as nitrobenzene have been investigated and the observed quenching in fluorescence have been corroborated by theoretical calculations.

A new ZnII metal-organic framework, [Zn6 (L)3 (DMA)4 ]⋅5 DMA (H4 L=[1,1':3',1''-terphenyl]-3,3'',5,5''-tetracarboxylic acid, DMA=dimethylacetamide), has been synthesized and characterized. The structure contains a three-dimensional 3,4,4,6-connected net with (4.62 )2 (66 )(66 )(42 .610 .83 ) topology and displays selective detection of nitrobenzene, CrO42- and Fe3+ ions. The present work thus indicates that this metal-organic framework could be a prospective candidate for developing novel luminescence sensors for the selective sensing of nitrobenzene, which can be used as a precursor for explosives. Furthermore, the photoluminescent properties of this material in different solvents and with various analytes were investigated and corroborated by theoretical calculations. The results were in good agreement with the experimental solvent-dependent luminescence behavior.

A new metal–organic framework having the formula (NH2(CH3)2)[Zn2(OAc)(L)]·0.5DMF (H4L = 2,5-di(3′,5′-dicarboxylphenyl)pyridine) (GDMU-3) has been synthesized and characterized. The net of GDMU-3 is uninodal and is closely related to the lvt net, which has the same Schlafli symbol of 42·84. GDMU-3 displays selective properties for the detection of nitrobenzene and Fe3+ ions. Remarkably, GDMU-3 exhibits an excellent capability to adsorb methylene blue with high selectivity. The present work indicates that GDMU-3 could be a potential candidate for developing novel luminescence sensors for the selective sensing of nitrobenzene which can be deployed for explosives, Fe3+ and organic dyes.

An unusual Cu(II) coordination polymer [Cu(Him)2(L)] (1) having a 4,4′-{[1,2-phenylene bis-(methylene)]bis(oxy)}dibenzoic acid ligand and an imidazole ligand possessing a 1D zig-zag chain was constructed and its magnetic behaviour was investigated, which indicated a magnetic phase transition below 25 K as well as long-range magnetic ordering.

A new compound of (NH2(CH3)2[Zn3(L)2·3.5DMF]) (1) (H4L = 1,1′,4′,1″,4″,1‴-quaterphenyl-3,5,3‴,5‴-tetracarboxylic acid 1,3,5-benzenetrisbenzoate) was synthesized and characterized. The coordination polymer shows an unusual 4,8-connected 3D net with (46)2(412·612·84) topology. The incorporation of the drug 5-fluorouracil (5-FU) into the desolvated 1 was around 22.5 wt.% per gram of dehydrated 1. 5-Fu is released in a highly controlled and progressive fashion with 92% of the drug released after 120 h. The result from this work provides a new avenue for MOF to be used as potential drug delivery.

Using CFD to simulate the flow field of impinging jet mixer in polyurea spraying gun,discussing the process of the spraying and jointing of the mixer after studying the profile of velocity and pressure.Spraying and jointing are available for the nozzle by changing the inlet pressure, the export velocity is slow under low pressure, so the outburst changes into a stream of flow and the jointing function is realized;while the export velocity is fast when the pressure is high,so the flow spray out to realize the spraying function.The distribution of the pressure and velocity within the mixer is extremely uneven,this is helpful for part A and part B mixing in the mixer.

AIM: To characterize the correlation between severity of hepatopulmonary syndrome (HPS) and degree of hepatic dysfunction, and to explore how intestinal endotoxemia (IETM) affects the development of HPS in cirrhotic rats. METHODS: Male Wister rats were fed with a diet containing maize flour, lard, cholesterol, and alcohol and injected subcutaneously with CCl4 oil solution every two days for 8 wk to induce typical cirrhosis and development of HPS. The animals were also given a nitric oxide (NO) production inhibitor, Nω-nitro-L-arginine methyl ester (L-NAME) intraperitoneally, and an iNOS inhibitor, aminoguanidine hydrochloride (AG) via gavage daily from the end of the 4th wk to the end of the 6th or 8th wk, or a HO-1 inhibitor, zinc protoporphyrin (ZnPP) intraperitoneally 12 h prior to killing. Blood, liver and lung tissues were sampled. RESULTS: Histological deterioration of the lung paralleled to that of the liver in the cirrhotic rats. The number of pulmonary capillaries was progressively increased from 6.1 ± 1.1 (count/filed) at the 4th wk to 14.5 ± 2.4 (count/filed) at the 8th wk in the cirrhotic rats. Increased pulmonary capillaries were associated with increased blood levels of lipopolysaccharide (LPS) (0.31 ± 0.08 EU/mL vs control 0.09 ± 0.03 EU/mL), alanine transferase (ALT, 219.1 ± 17.4 U/L vs control 5.9 ± 2.2 U/L) and portal vein pressure. Compared with normal control animals, the number of total cells in bronchoalveolar lavage fluid (BALF) of the cirrhotic rats at the 8th wk was not changed, but the number of macrophages and the ratio of macrophages to total cells were increased by nearly 2-fold, protein expression of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) started to increase significantly at the 4th wk, and reached its peak at the 8th wk in the lung of cirrhotic rats. The increase of iNOS expression appeared to be quicker than that of eNOS. NO2-/NO3- was also increased, which was correlated to the increase of iNOS (r = 0.7699, P < 0.0001) and eNOS (r = 0.5829, P < 0.002). mRNA expression of eNOS and iNOS was highly consistent with their protein expression. CONCLUSION: Progression and severity of HPS as indicated by both increased pulmonary capillaries and histological changes are closely associated with LPS levels and progression of hepatic dysfunction as indicated by increased levels of ALT and portal vein pressure. Intestinal endotoxemia plays a central role in the development of HPS in the cirrhotic rat model by inducing NO and/or CO.