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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.

Energy integration relies on matching process hot streams with process cold streams, and utilities are only introduced to balance the deficit in energy consumption. A systematic but simple Pinch Analysis (PA)-based retrofit approach is proposed to lessen the utility consumption of any industrial heat exchanger network (HEN) under new minimum temperature approach (ΔTms) at the cost of minor capital investment. This work is an extended and improved version of our previous work ( Li and Chang, 2010 ). Elaborate visualized tool of T–H diagram for identification of cross-pinch heat load is proposed to fully address the case that phases change in the cross-pinch heat exchanger. Main characters of industrial HENs which are large scale, varied heat capacity flow rate and multiple pinches are fully addressed. Specifically, each cross-pinch exchanger or match is identified and those matches with large cross-pinch loads are disconnected first, and then their heat loads on the hot and cold stream side are split according to pinch temperatures. Next, at either side of or between the pinches, the divided heat loads on each stream are combined and matched according to a systematic Pinch Analysis (PA) based procedure. Retrofit modifications are focused on those cross-pinch matches and utility exchangers, so the retrofit procedure of an industrial HEN is obviously simplified. An industrial case of Crude oil preheat train (COPT) is retrofitted to demonstrate the effectiveness of the proposed approach.

A new three-dimensional microporous metal–organic framework based on Zn(II) clusters with the formula {[Zn7(NDC)5.5(μ4-OH)3]·7DMF}n (1) (H2NDC = 1,4-naphthalenedicarboxylic acid) had been synthesized and characterized. The MOF 1 displays an uncommon bsn topology, which is based on a unique heptanuclear Zn7(OH)3(CO2)11 cluster as a secondary building unit. The MOF had been employed as a photocatalyst for the photodegradation of model organic dyes rhodamine B and methyl violet in light. The results of photocatalytic experiments showed that 1 can successfully be employed as the photocatalyst for the benign decomposition of these dyes. A mechanism for the photcatalysis exhibited by 1 had been proposed using the results of density of states (DOS) and partial DOS calculations. The fluorescence properties of the MOF have been investigated, which revealed that 1 could be exploited as the luminescent sensor to recognize Fe3+ ions with perceptible quenching (Ksv = 6.55 × 104 M–1) and a limit of detection of 1.16 ppm.

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.

Rational designing of carbon-based adsorbent precursors is an important way to enhance adsorption performance. In this work, fascinating Co@C composites have been designed and fabricated using a new cobalt-seamed metal-organic nanocapsule (Co-MONC), which exhibits incredibly high adsorption capacity for chlorpromazine (CPZ) removal from aquatic environments. Benefiting from its interconnected micro- and mesoporous structures, well-dispersed and highly available Co adsorption active sites, the optimal Co@C-900 exhibits ultrahigh CPZ adsorption capacity (1039.53 mg g-1) and excellent recycling ability, outperforming the reported porous materials and commercial activated carbon. Moreover, the adsorption behaviors of CPZ for the composite have been comprehensively investigated and the plausible adsorption mechanism was proposed. Apart from this, the interaction mechanism between exposed Co adsorption active sites and CPZ have been suggested with the aid of density functional theory (DFT) calculations. The presented investigation demonstrated a facile and designable strategy for the fabrication of highly effectively adsorbents for organic contaminant removal.

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.

Since the conventional design strategies for interplant heat integration usually focused upon minimization of the overall utility cost, the optimal solutions may not be implementable due to the additional need to distribute the financial benefits “fairly.” To resolve this profit sharing issue, a Nash-equilibrium constrained optimization strategy has already been developed to sequentially synthesize heat exchanger networks (HENs) that facilitate direct heat transfers across plant boundaries. Although this available approach is thermodynamically viable, the resulting network may be highly coupled and therefore inoperable. To address the operability issues in any multi-plant HEN, the present study aims to modify the aforementioned strategy by considering only indirect interplant heat-exchange options. Two separate sets of mathematical programming models are developed in this work for generating the total-site heat integration schemes with the available utilities and an extra intermediate fluid, respectively. The negotiation powers of the participating plants are also considered for reasonably distributing the utility cost savings and also shouldering the capital cost hikes. Finally, extensive case studies are presented to demonstrate the effectiveness of the proposed procedures and to compare the pros and cons of these two indirect heat-exchange alternatives.

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).

A NbO-type Zn(II) metal–organic framework of {[Zn2(HL)(H2O)2]∙H2O}n (1) has been developed using a pentacarboxylate 2,5-bis(3′,5′-dicarboxylphenyl)-benzoic acid (H5L) ligand and characterized. The single-crystal X-ray diffraction studies indicate that 1 comprises free –COOH groups and Zn(II) centers bridged by four carboxylate groups to form a paddle wheel SBU which is further connected by L5− ligands to build a 3-D porous network with two types of cages. The chemically stable MOF 1 behaves as a highly selective and sensitive fluorescent chemosensor for the detection of Fe3+ ions, 2,4,6-trinitrophenol (TNP), which is known to be an extremely hazardous and strong explosive. Furthermore, the photocatalytic properties of 1 for degradation of methyl violet (MV) and Rhodamine B (RhB) have been explored. The possible emission quenching mechanism in the presence of nitro-aromatics (NACs) has been addressed by theoretical calculations and photocatalytic activity of 1 against organic dyes has been supported using density of states (DOS) calculations.

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 Zn(II) metal–organic framework of [Zn 6 (L) 3 (DMA) 4 ]·5DMA ( 1 ) (H 4 L = [1,1′:3′,1″-terphenyl]-3,3″,5,5″-tetracarboxylic acid), was used as a drug carrier of 5-fluorouracil (5-FU) for drug delivery. Drug release behavior was also investigated under different pH condition. 5-FU is released in a highly controlled and progressive manner with 95.8% of the drug release after 96 h at acidic condition and with 91.6% after 96 h at PBS. Vitro cytotoxicity assays indicated that the 1 possesses no obvious cytotoxicity.

An unusual nanocage-based framework of [Zn 2 (L)(H 2 O) 1.5 ]·5H 2 O ( 1 ) was used as a drug carrier of 5-fluorouracil (5-FU) for drug delivery. The incorporation of drug 5-FU into the 1 was around 48.6 wt% per gram of dehydrated 1 . 5-FU is released in a highly controlled and progressive manner with 98% of the drug release after 101 h at acidic condition and with 62% after 72 h at PBS. 1 did not exhibit any significant cytotoxicity using the vitro cytotoxicity assays. The result from this study suggested a new approach for MOFs to be used as potential drug delivery.

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.

BACKGROUND: Bronchial hyperresponsiveness (BHR) has not been extensively performed in preschool children, possibly because of the difficulty in cooperating with the tests. We sought to determine the usefulness and safety of methacholine bronchial provocation test (MCh-BPT) for BHR assessment in preschool children. METHODS: We recruited 252 preschool children (190 healthy and 62 with wheezing) who underwent MCh-BPT at baseline. MCh-BPT was re-scheduled in case initial attempts failed. Forced expiratory volumes in 0.5 (FEV(0.5)), 0.75 (FEV(0.75)) and one second (FEV(1)) were measured. We recorded the provocative dose causing 15% (PD(15)) or 20% reduction (PD(20)) in FEV(0.5), FEV(0.75) and FEV(1), thus allowing for comparison of the diagnostic value of PD(15) and PD(20). RESULTS: A total of 209 children [156 (82.1%) healthy, 53 (85.5%) with wheezing] successfully completed MCh-BPT. Compared with healthy children, a significantly greater proportion of children with wheezing had measurable PD(15)FEV(0.5), PD(15)FEV(0.75) and PD(15)FEV(1) (P

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.

A new fabrication of [Cu3(μ2-H2O)(PHB)(H2O)]·(DMF)3(H2O)6 (GDMU-2) was synthesized and used as a drug vehicle of 5-Fluorouracil (5-FU) for drug delivery. The incorporation of the drug 5-FU into the GDMU-2 was around 53.7 wt% per gram of dehydrated GDMU-2. Cargo release behavior and material degradation profile were also investigated under different pH. 5-FU is released in a highly controlled and progressive manner with 100% of the drug release after 97 h at acidic condition and with 83% after 132 h at PBS. In vitro cytotoxicity assays indicated that the GDMU-2 possesses no obvious cytotoxicity. The result from this work provides a new avenue for MOF to be used as potential drug delivery.

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 phytochemical-containing metal–organic framework of {[Zn2(fer)2]}n (H2fer = ferulic acid) (1) was used as a matrix for the adsorption and in vitro drug carrier of 5-fluorouracil (5-FU). The 5-FU delivery ability, biodegradation, and cytotoxicity of 1 was also studied. Additionally, the grand canonical ensemble Monte Carlo (GCMC) simulation was performed to investigate the loading of 5-FU to 1 at the molecular level. The results of GCMC simulations validated the experimental trend with respect to drug loading capacity of 1. According to radial distribution function (RDF) and configuration snapshot analysis, the main driving forces for the loading of 5-FU on 1 are hydrogen bonding interactions. Our investigation also revealed that the adsorption energies of 1 are constant when drug loading changes. This may lead to a long-time stable release of anti-cancer agents, and could reduce side-effects for patients.

An improved rate-based model of the typical CO2 capture process by aqueous MonoEthanolAmine (MEA) solution is built within Aspen Plus V8.0 software in this study. The improved model is built on the basis of an example model coming along with Aspen Plus V8.0, and thermodynamic model of ENRTL-RK is adopted. Improvements include the washing section of the absorption column is strictly modelled by a separate column, and the error on mass balance of MEA is greatly reduced. The new model is validated by the recently published pilot-scale experimental results of the absorption of CO2 by MEA solution, in which both absorption and desorption columns are equipped with the structured packing Sulzer Mellapak 250.Y™. It predicts the experimental profiles of the temperature and the concentration of CO2 in the liquid phase with an accuracy of ±4%, and obviously much better than recently reported model with an accuracy of ±8%. Important insights have been obtained on the function of washing sections on the top of both absorber and desorption column, the factors to determine the flowrates of make-up water and recycle water around the washing section of the absorber are first analyzed.

Around 21% of the world’s power production is based on natural gas. Energy production is considered to be the significant sources of carbon dioxide (CO2) emissions. This has a significant effect on the global warming. Improving power plant efficiency and adding a CO2 capture unit into power plants, have been suggested to be a promising countermeasure against global warming. This paper presents a new insight to the application of energy efficient technologies in retrofitting natural gas combined cycle (NGCC) power plants with CO2 capture. High fidelity models of a 420 MW NGCC power plant and a CO2 capture plant with CO2 compression train have been built and integrated for 90% capture level. These models have been then validated by comparisons with practical operating data and literature results. The novelty of the paper is to propose optimal retrofitting strategies to minimize the efficiency penalty caused by integrating carbon capture units into the power plant, including (1) implementing heat transfer intensification techniques to increase energy saving in the heat recovery steam generator (HRSG) of the power plant; (2) extracting suitable steam from the HRSG to supply the heat required by the capture process, thus on external heat is purchased; (3) employing exhaust gas recirculation (EGR) to increase the overall energy efficiency of the integrated process, which can benefit both power plant (e.g. increasing power plant efficiency) and capture process (e.g. reducing heat demands). Compared with the base case without using any integrating and retrofitting strategies, the optimal solution based on the proposed approaches can provide sufficient heat to CO2 capture process, and keep the same power generation. The optimal solution shows that, the flue gas flow-rate is reduced 33% in the inlet of CO2 capture process, heat demand in CO2 capture decreases 4.3%, heat output from the power plant increases from 0 MW to 133 MW, and more than 22% of profit is obtained in the integrated system. This demonstrates the validity and efficiency of the proposed approaches in retrofitting existing NGCC power plants with CO2 capture.

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.

A highly connected metal–organic framework (MOF), namely, [Co5(μ3-OH)2(iapt)4(4,4′-bipy)0.5(H2O)·CH3CN·3H2O] (1) (H2iapt = 5-aminoisophthalic acid and 4,4′-bipy = 4,4′-bipyridine), is reported. 1 shows a complicated pentanodal 4,4,4,4,13-c 3D net with (43)(43)(43)(43)(420·514·623·78·813) topology based on an uncommon Co5 cluster. The magnetic analysis reveals antiferromagnetic interactions in 1, and both the local spin–orbit coupling of octahedral Co(II) ions and the antiferromagnetic interactions are the primary factors in the magnetic behaviour.

To study the role of Notch1 signaling pathway in the myocardial protective effects of resveratrol pro-treatment after hepatic ischemia/reperfusion injury.Thirty-six healthy male SD rats were randomly divided into 3 groups:sham control (SC) group, hepatic ischemic/reperfusion (HIR) group, and pro-treatment resveratrol (Res) group,12 rats in each group. After each group with hepatic ischemia 40 min reperfusion 2 h (SC group placing equal time), the left ventricular function including left ventricular pressure (LVP), left ventricular systolic pressure (LVSP) and its derivate (±dp/dt) was measured; the serum activities of creatine kinase isoenzyme (CK-MB) and lactate dehydrogenase (LDH) and tumor necrosis factorα(TNF-α) and interleukin-6(IL-6) were detected. The activity of myocardial su-peroxide dismutase(SOD) and contents of myocardial malonaldehyde (MDA) were determined; Notch intracellular domain (NICD) expressions were detected with Western blot; the mRNA levels of Notch1 and TNF-αwere detected by real-time PCR.Compared with SC group, the left ventricular functions in the HIR group were significantly decreased. With decreasing the expression of NICD and Notchl, the activities of CK-MB, LDH, TNF-αand IL-6 in the serum were evidently increased(The findings indicate that resveratrol has protective effect on myocardial injury during the hepatic ischemia/reperfusion, and its mecha-nisms may be related to anti-inflammation and anti-oxidative stress

To investigate whether the phosphatidyl-inositol-3-kinase/protein kinase B(PI3K/Akt)pathway is involved in anti-arrhythmia of resveratrol on ischemia/reperfusion in rat hearts.Forty male rats of normal ECG were randomly divided into 4 groups (The phosphorylated levels of Akt and myocardial Cx43 were significantly enhanced in Res group as compared with I/R group(Resveratrol could prevent the occurrence of reperfusion arrhythmias by increasing the content and ac-tivity of myocardial Cx43 through the PI3K/Akt signaling pathway.

Two isostructural nanoporous MOFs with [Zn3(μ3-O)(BTC)2(H3O)]n (NTU-Z11) and {[Zn3(μ3-O)(BTC)2(DMF)]·2NH2(CH3)2·4H2O}n (GDMU) (BTC = 1,3,5-benzenetricarboxylate) have been used as drug carriers of 5-fluorouracil (5-FU). The incorporation of 5-FU into the desolvated NTU-Z11 and GDMU was around 0.38 g g−1 and 0.22 g g−1, respectively. NTU-Z11 presents pH-triggered controlled drug release properties in pH 6.0, 7.4 and 9.18 and water media. In addition, we performed GCMC simulations to investigate the loading of 5-FU into NTU-Z11 and GDMU at the molecular level. The results from simulations reproduce the experimental trend with respect to the drug loading capacity of each material. A comparison between the calculated drug loading values and some molecular level properties indicates the existence of a relationship between the void space of the material and the drug loading capacity.

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.

This paper1 introduces the notion of attribute-based concurrent signatures. This primitive can be considered as an interesting extension of concurrent signatures in the attribute-based setting. It allows two parties fairly exchange their signatures only if each of them has convinced the opposite party possesses certain attributes satisfying a given signing policy. Due to this new feature, this primitive can find useful applications in online contract signing, electronic transactions and so on. We formalize this notion and present a construction which is secure in the random oracle model under the Strong Diffie-Hellman assumption and the eXternal Diffie-Hellman assumption.

A systematic but simple pinch-based retrofit procedure is developed to lower the utility consumption levels of any given industrial Heat Exchanger Network (HEN) under new minimum temperature approach at the cost of minor capital investment. This work is an extended and improved version of our previous work (Li and Chang, 2010). New visualized identification method for cross-pinch heat load is proposed to cover the case that phases change in the cross-pinch heat exchanger. Main characters of industrial HENs which are large scale, varied heat capacity flow rate and multiple pinches are fully addressed. Specifically, each cross-pinch exchanger is identified and those exchanges with large loads are removed first, and then, their heat loads on the hot and cold streams are both divided according to pinch temperatures. Next, at either side of or between the pinches, the divided heat loads on each stream are combined to remove small heat loads and matched according to a systematic procedure derived from simple pinch analysis. Note that modifications are focused on those cross-pinch matches and utility exchangers, which greatly simplifies the retrofitting procedure of an industrial HEN. An industrial case of Crude Oil Preheat Train (COPT) is retrofitted to illustrate the effectiveness of the proposed procedure.

As an opposite process of language acquisition, language attrition has been studied over 30 years abroad and established a relatively complete system of theory and particular research access. In this paper, the authors mainly introduce the researches of language attrition domestic and abroad, the typology of language attrition, two theories of language attrition. In the end, the authors analyze the inspirations of language attrition to Chinese College English teaching and acquisition.

Due to specific immune recognition receptors on the surface of T cells, their membranes are promising mimic nanocarriers for delivering drugs to tumor lesions. However, this single targeting strategy potentially compromises therapy efficacy for tumor targeting due to inter‐ and intra‐heterogeneity of tumors. Azide (N3) or bicyclo [6.1.0] nonyne (BCN) modified unnatural sugars can be successfully incorporated into surface glycans of various tumor cells as artificial receptors, which is expected to overcome the insufficiency of single targeting. Based on this artificial tumor targeting strategy, indocyanine green nanoparticles (INPs) coated with N3‐labeled T cell membrane (N3‐TINPs) are constructed, which can specifically target the natural antigen and BCN artificial receptors on tumors through immune recognition and bioorthogonal chemistry, respectively. The results show that the fluorescence intensity in the tumors of mice treated with N3‐TINPs is 1.5 fold compared with that of the mice treated with unlabeled TINPs. The accumulated N3‐TINPs in the tumor significantly increase the photothermal therapeutic effect without adverse effect. Therefore, this T cell membrane mimicking nanoparticles based bioorthogonal chemistry may provide an alternative artificial targeting strategy for further tumor targeting photothermal therapy.

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.

A new Zn

Luminescent metal-organic frameworks (LMOFs) containing fluorescent probes for the detection of pollutants such as organic solvents and heavy metals are becoming increasingly important, with lanthanide-MOF (Ln-MOF) materials receiving greater attention owing to the possibility of achieving fine-tuned luminescent properties. Herein, two unusual isostructural nanocage-based three-dimensional Ln-MOFs, 1-Ln (Ln=Tb, Eu), are constructed, using a new diisophthalate ligand with active Lewis basic triazole sites. Selective gas adsorption, especially the removal of CO

Three new metal organic frameworks (MOFs) with chemical formulae [(CH3)2NH2] [Sm3(L1)2(HCOO)2(DMF)2(H2O)]·2DMF·18H2O (1), [Cu2(L2)(H2O)2]·2.22DMA (2) and [Zn2(L1)(DMA)]·1.75DMA were synthesized and structurally characterized. 1 and 2 show a classical NbO-like topology and have two types of interconnected cages. 3 exhibits an uncommon zzz topology and has two types of interconnected cages. These MOFs can adsorb large amounts of the drug 5-fluorouracil (5-FU) and release it in a progressive way. 5-FU was incorporated into desolvated 1, 2 and 3 with loadings of 0.40, 0.42, and 0.45 g g(-1), respectively. The drug release rates were 72%, 96% and 79% of the drug after 96 hours in 1, 120 hours in 2 and 96 hours in 3, respectively. Grand Canonical Monte Carlo (GCMC) simulations were performed to investigate the molecular interactions during 5-FU adsorption to the three novel materials. The GCMC simulations reproduced the experimental trend with respect to the drug loading capacity of each material. They also provided a structural description of drug packing within the frameworks, helping to explain the load capacity and controlled release characteristics of the materials. 5-FU binding preferences to 1, 2 and 3 reflect the diversity in pore types, chemistry and sizes. The calculated drug load is more related to the molecular properties of accessible volume Vacc than to the pore size.

To investigate the effects of ischemic postconditioning (IPTC) on the changes of matrix metalloproteinases-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) protein and mRNA levels in rat heart subjected to ischemia/reperfusion, and explore the mechanism by which IPTC protects myocardial interstitium following ischemic/reperfusion (I/R).Twenty four healthy male SD rats were randomly divided into 3 groups (n = 8): sham control (SC) group, I/R group and IPTC group. The parameters of left ventricular function including left ventricular systolic pressure (LVSP) and its derivate (±dp/dt) were measured; the amount of myocardial collagen contents was determined by hydroxyproline quantification; the plasma activity of creatine kinase (CK) and lactate dehydrogenase (LDH) was detected; the protien levels of MMP-2 and TIMP-2 was measured by Western blot and the mRNA levels of MMP-2 and TIMP-2 was detected by real-time PCR.The myocardial collagen contents, left ventricular function and the protein and mRNA levels of TIMP-2 were significantly decreased in I/R group compared with those of SC group, wherease the activities of CK and LDH in the plasma and the protein and mRNA levels of MMP-2 were significantly enhanced in I/R group when compared to SC group. Compared with I/R group, the myocardial collagen contents, left ventricular function and the protein and mRNA levels of TIMP-2 were increased in IPTC group, the activities of CK and LDH in the plasma and the protein and mRNA level of MMP-2 were decreased in IPTC group.These findings indicate that IPTC has protective effects on myocardial interstitial after the myocardial ischemia/reperfusion injury, and IPTC may exert its cardioprotectve effect via inhibiting MMP-2 and enhancing TIMP-2 expression in cardiac muscle.