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The tetrel-bonded complexes formed between the selected boron-substituted carbenes and TH3F (T = C, Si, Ge, Sn, Pb) have been explored by using the high-level quantum chemical method. The binding sites of TH3F in the complexes are generally consistent with the positions of VS,min points of the carbenes, and the -Eint values of the complexes exhibit a general increasing tendency with the increase of the -VS,min values of the carbenes for a given TH3F. The complexes can be divided into the type-I and type-II groups. The type-I complexes are characterized by the 3c(B-C-B)→BD*(T-F) and BD(B-C)→BD*(T-F) orbital interactions, and the type-II complexes are characterized by the LP(C)→BD*(T-F) orbital interactions. The type-II complexes have more negative Eint values than the type-I complexes. The -Eint values of the type-I complexes exhibit a roughly increasing tendency with the increase of the T atomic number, and the -Eint values go in the order SnH3F > PbH3F > GeH3F > SiH3F > CH3F for most type-I complexes, which is consistent with the order of VS,max values of TH3F. Unlike type-I complexes, the -Eint values of the type-II complexes exhibit a zigzag tendency with the increase of the T atomic number, and the -Eint values go in the order SiH3F > SnH3F > GeH3F > PbH3F > CH3F for type-II complexes. The AIM and SAPT analysis has been employed to explore the nature of the intermolecular interactions in these complexes. [ABSTRACT FROM AUTHOR]

The intermolecular complexes formed between imidazol-2-ylidene and its heavy-atom analogues C2H4N2X: (X = C, Si, Ge, Sn, Pb) and YH3F (Y = Si, Ge, Sn, Pb) have been optimized at the MP2/aug-cc-pVTZ level. C2H4N2X: have two electron-rich moieties, one of which is the lone pair on the X atom and the other is the 6π-electron system. Three types of binding modes (type-A, type-B and type-C) can be distinguished for C2H4N2X: according to the locations of YH3F. The type-A and type-B complexes can be located for C2H4N2C:···YH3F system, and the Eint values of the type-A complexes are much larger than those of the type-B complexes. The type-A, type-B and type-C complexes can be located for the other four systems, and the Eint values of these complexes go in the order type-B > type-C > type-A. The binding strength of the type-A complexes becomes weaker, and that of the type-B and type-C complexes becomes stronger with the increase of the X atomic number for C2H4N2X:···YH3F system, which can be clarified by the MEP maps of C2H4N2X:. The NBO, AIM and SAPT analysis was employed to explore the nature of the interactions in these complexes. [ABSTRACT FROM AUTHOR]

The dual binding behavior of the metallylenes TH2 (T = Si, Ge, Sn, Pb) with some selected Lewis acids (T'H3F, T' = Si, Ge, Sn, Pb) and bases (N2, HCN, CO, and C6H6) has been investigated by using the high-level quantum chemical method. Two types (type-A and type-B) of tetrel-bonded complexes can be formed for TH2 due to their ambiphilic character. TH2 act as Lewis bases in type-A complexes, and they act as Lewis acids in type-B ones. CO exhibits two binding modes in the type-B complexes, one of which is TH2···CO and the other is TH2···OC. The TH2···OC complexes possess a weaker binding strength than the other type-B complexes. The TH2···OC complexes are referred to as the type-B2 complexes, and the other type-B complexes are referred to as the type-B1 complexes. The type-A complexes exhibit a relatively weak binding strength with Eint (interaction energy) values ranging from –7.11 to –15.55 kJ/mol, and the type-B complexes have a broad range of Eint values ranging from −9.45 to −98.44 kJ/mol. The Eint values of the type-A and type-B1 complexes go in the order SiH2 > GeH2 > SnH2 > PbH2. The AIM (atoms in molecules) analysis suggests that the tetrel bonds in type-A complexes are purely closed-shell interactions, and those in most type-B1 complexes have a partially covalent character. The EDA (Energy decomposition analysis) results indicate that the contribution values of the three energy terms go in the order electrostatic > dispersion > induction for the type-A and type-B2 complexes, and this order is electrostatic > induction > dispersion for the type-B1 complexes. [ABSTRACT FROM AUTHOR]

Methods: The intermolecular interactions between the heavy-atom analogues of acetylene T2H2 (T = Si, Ge, Sn, Pb) and HCN have been investigated by theoretical calculations at the CCSD(T)/aug-cc-pVTZ//MP2/aug-cc-pVDZ level. Results: The global energy minimum of T2H2 is the butterfly structure A, and another energy minimum is the planar structure B. Both structures A and B exhibit the dual behavior when binding with HCN. The various hydrogen bond (HB), dihydrogen bond (DB) and tetrel bond (TB) complexes can be found according to the MEP maps of T2H2. One TB and three HB complexes formed between structure A and HCN can be located for Si2H2 and Ge2H2. One TB, two HB and one DB complexes formed between structure A and HCN can be located for Sn2H2 and Pb2H2. Four TB and one HB complexes formed between structure B and HCN can be located for all the T2H2. The geometries and binding strengths of the complexes are compared and analyzed. Conclusions: The interactions in these complexes are generally weak, and the interaction energies of these complexes range from −0.53 to −8.23 kcal/mol. The interaction energies of the TB complexes are larger than those of the corresponding HB and DB complexes for structure A···HCN systems. The relative binding strength of the four TB complexes exhibits different order for different structure B···HCN systems, which is consistent with the MEP maps of the isolated monomers. [ABSTRACT FROM AUTHOR]

The intermolecular interactions between the heavy alkenes H2Si = TH2 (T = C, Si, Ge, Sn, Pb) and C2H2 have been calculated at the CCSD(T)/aug-cc-pVTZ//MP2/aug-cc-pVDZ level, and the nature of these complexes has been investigated by natural bond orbital. The four types (type-A, type-B, type-C and type-D) of complexes can be located for H2Si = TH2···C2H2 system. The complexes involving H2Si = TH2···C2F2 and H2Si = TH2···C2(CN)2 have also been examined to explore the substituent effects. Some complexes which are stable for H2Si = TH2···C2H2 system become unstable for H2Si = TH2···C2F2 or H2Si = TH2···C2(CN)2 system, while other complexes which are unstable for H2Si = TH2···C2H2 system become stable for H2Si = TH2···C2F2 or H2Si = TH2···C2(CN)2 system. [ABSTRACT FROM AUTHOR]

Background: The purpose of this meta-analysis is to compare the safety and efficacy of en bloc transurethral resection of bladder tumor (EBRT) versus conventional transurethral resection of bladder tumor (CTURBT). Methods: We performed a meta-analysis of relevant articles through November 2019 using PubMed, Embase, and Cochrane Central Register to compare the safety and efficacy of EBRT versus CTURBT. The main endpoint included the operation time (OT), hospitalization time (HT), catheterization time (AT), perioperative period complications, bladder detrusor muscle found in the specimen, the residual tumor on the base, the ratio of the same site recurrence, and 12/24/36-month recurrence rate. Cochrane Collaboration's Revman software, version 5.3, was used for statistical analysis. Results: A total of 19 studies with 2651 patients were included, 1369 underwent EBRT and 1282 underwent CTURBT. Patients treated with EBRT had a significantly lower AT, HT, obturator nerve reflex, bladder perforation, bladder irritation, postoperative complications, and 24-month recurrence rate than those who underwent CTURBT. While no significant difference was found in terms of OT, the ratio of bladder detrusor muscle found in the specimen, the residual tumor on the base, 12-month recurrence rate, 36-month recurrence rate, and the ratio of the same site recurrence. In mitomycin subgroup, EBRT was superior to CTURBT in terms of 12/24-month recurrence rate. Similarly, in the prospective subgroup and retrospective subgroup, EBRT had a lower 24-month recurrence rate than CTURBT. However, no significant difference was found in the low, intermediate, and high-risk group in the light of 12–36-month recurrence rate. Conclusions: Based on the included 19 articles, EBRT had a significantly lower AT, HT, intraoperative and postoperative complications, and 24-month recurrence rate than those treated with CTURBT. Well-designed randomized controlled trials were needed to reevaluate these outcomes. Trial registration: This meta-analysis was reported in agreement with the PRISMA statement and was registered on PROSPERO 2019 CRD42019121673. [ABSTRACT FROM AUTHOR]

The binary and ternary complexes composed of GeH3F, AsH2F and ring compounds (benzene, borazine and cyclopentadienyl anion) have been studied by theoretical calculations to understand the interplay between the tetrel bond and pnicogen bond interactions. The bonding strength of intermolecular interactions in these complexes is analyzed by means of atoms in molecules (AIM), natural bond orbital (NBO) and noncovalent interaction (NCI) index methods. The binary tetrel-bonded and pnicogen-bonded complexes can be classified as an n-type or π-type complex according to the orbital interactions involved in the complexes. Three binding modes can be distinguished according to the interplay between interactions for the ternary complexes. The binding mode A is characterized by the interplay between π-type tetrel bond and n-type pnicogen bond; binding mode B is characterized by the interplay between π-type pnicogen bond and n-type tetrel bond, and binding mode C is characterized by the interplay between π-type tetrel bond and π-type pnicogen bond. The binding modes A and B exhibit the synergistic interplay effect, while the antagonistic effect is reflected in mode C. The synergistic effect in binding modes A and B is stronger than antagonistic effect in mode C, and the synergistic effect in binding mode B is stronger than that in mode A. [ABSTRACT FROM AUTHOR]

Preeclampsia (PE) is a hypertension-associated disease, and resveratrol (RES) is a polyphenol recognized to present beneficial effects in cardiovascular disease including hypertension. Recently, attentions have come to the therapeutic effect of RES in PE, but the underlying molecular mechanisms remain largely unknown. This study sought to delineate the mechanistic basis regarding bioinformatically identified miR-363-3p/PEDF/VEGF axis for RES treatment in PE. PE-like symptoms were induced in vivo in Sprague-Dawley rats by intraperitoneal injection with Ng-nitro-L-arginine methyl ester (L-NAME), and hypoxia was induced in vitro in trophoblasts by CoCl 2. Accordingly, RES was found to enhance viability, migration, angiogenesis, and to repress the apoptosis of hypoxic trophoblasts in vitro. Furthermore, in vivo experiments noted that RES alleviated placental injury and promoted angiogenesis in rats with PE-like symptoms in vivo by increasing VEGF via promoting miR-363-3p-mediated PEDF suppression. Collectively, RES ameliorates PE by upregulating VEGF through miR-363-3p-mediated PEDF downregulation, the mechanism of which may be of promising significance to augment RES efficacy in PE treatment. • RES enhances growth dynamics of hypoxic trophoblasts. • miR-363-3p inhibits PEDF in placental tissues of PE-like rats and hypoxic trophoblasts. • RES downregulates PEDF by elevating miR-363-3p. • RES relieves PE by elevating VEGF through miR-363-3p-mediated PEDF inhibition. • This study provides mechanistic understanding of RES for PE treatment. [ABSTRACT FROM AUTHOR]

Efficient treatment of complex rare earth (RE) smelting wastewater has drawn great attention due to its potential environmental toxicity and the high demand of RE in modern technologies. However, it is still a challenge to achieve the simultaneous recovering RE and separating oil from wastewater. This study makes the first attempt to fabricate a versatile membrane, namely H-UiO-66-PF2, by loading 2-hydroxyphosphono acetic acid functionalized UiO-66 on polyester fabric through one-pot reaction strategy, and reports for the first time the simultaneous separation of oil/water mixtures and recovery of Gd(III). The H-UiO-66-PF2 exhibits standout oil/water separation performance with water flux up to 126,300 L·m−2·h−1 and separation efficiency above 99.8 %. Besides, the maximum adsorption capacity of H-UiO-66-PF2 for Gd(III) is reached 156.5 mg/g, adsorption equilibrium time is within 60 min. Moreover, the H-UiO-66-PF2 possesses high stability and recyclability, even after 20 cycles, separation efficiency and flux are 98.9 % and 105,200 L·m−2·h−1, respectively. Most notably, in addition to the separation of oil/water emulsion, complete Gd(III) capture is achieved from wastewater through filtration process. Therefore, this work provides a new design strategy to fabricate the composite membrane with great prospects for sophisticated smelting wastewater cleanup. [Display omitted] • A multifunctional membrane based on UiO-66 and polyester fabric is developed. • The membrane has a water flux of >126,300 L·m−2·h−1 with >99.8 % oil rejection. • The adsorption capacity of the membrane for Gd(III) is as high as 156.5 mg/g. • The membrane can simultaneously capture Gd(III) and separate oil-in-water emulsion. [ABSTRACT FROM AUTHOR]

Figures of persimmons for the world's top ten persimmon producing countries are about 4000,000 tons in 2011 and are increasing every year according to FAO statistics. However, there is not any report on pectin production by microbial with persimmon peel as the source. Optimization of fermentation conditions of pectin production from Aspergillus terreus in submerged culture and partial characterization of pectin were carried out in the work. An optimum fermentation condition for pectin production was obtained through a central composite rotatable design in response surface methodology as follows: fermentation time, 30.09 h, temperature, 25.00 °C and the initial pH in the fermentation medium, 6.90, respectively and the pectin yield reached the maximal value 0.449 g/g. Persimmon peel pectin had highly methoxylated (62.51%), high galacturonic acid content (82.28%) than citrus pectin, and was classified as the highly methoxylated pectin, the results indicated that persimmon peel had potential good resources for pectin production. The investigation can make it available to utilize persimmon peel to produce high methoxyl pectin for food industry, pharmacy and cosmetic manufacture. [ABSTRACT FROM AUTHOR]

The ternary complexes X · 1 · YF ( 1 = triazine, X = Cl, Br and I, Y = H, Cl, Br, I, PH and AsH) have been investigated by MP2 calculations to understand the noncovalently electron-withdrawing effects on anion-arene interactions. The results indicate that in binary complexes ( 1 · X), both weak σ-type and anion-π complexes can be formed for Cl and Br, but only anion-π complex can be formed for I. Moreover, the hydrogen-bonding complex is the global minimum for all three halides in binary complexes. However, in ternary complexes, anion-π complex become unstable and only σ complex can retain in many cases for Cl and Br. Anion-π complex keeps stable only when YF = HF. In contrast with binary complexes, σ complex become the global minimum for Cl and Br in ternary complexes. These changes in binding mode and strength are consistent with the results of covalently electron-withdrawing effects. However, in contrast with the covalently electron-withdrawing substituents, Cl and Br can attack the aromatic carbon atom to form a strong σ complex when the noncovalently electron-withdrawing effect is induced by halogen bonding. The binding behavior for I is different from that for Cl and Br in two aspects. First, the anion-π complex for I can also keep stable when the noncovalent interaction is halogen bonding. Second, the anion-π complex for I is the global minimum when it can retain as a stable structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • The rice husk-based ion-imprinted polymer (RH-CIIP) was used for simultaneously detection and recovery of Cu2+ was developed. • The RH-CIIP exhibits excellent adsorption capacity (87.8 mg/g) and selectivity for Cu2+. • The limit of detection of RH-CIIP was calculated as low as 5.62 μg/L. With the deepening of the concept of recycling economy and green chemistry, selective detection and capture of Cu2+ from lake water by biosorbent are of great significance. Herein, the Cu2+ ion-imprinted polymers (RH-CIIP) with organosilane containing hydroxyl and Schiff base groups (OHSBG) as ion-receptor, fluorescent chromophores and cross-linking agent, and Cu2+ as template ion, were fabricated via surface ion imprinting technology by employing mesoporous silica MCM-41 (RH@MCM-41) as supporter. The RH-CIIP could be exploited as a fluorescent sensor for Cu2+ with high selective compared with Cu2+ non-imprinted polymers (RH-CNIP). Additionally, the LOD was calculated to be 5.62 μg/L, which is far below WHO standard for Cu2+ in drinking water of 2 mg/L, and more lower than the reported methods. Moreover, the RH-CIIP can also be utilized as an adsorbent for the effective elimination of Cu2+ from lake water with the adsorption capacity of 87.8 mg/g. Besides, the kinetic features of adsorption were well defined by the pseudo-second-order model and the sorption isotherm was in agreement with the Langmuir model. Meanwhile, the interaction of RH-CIIP and Cu2+ was investigated using theoretical calculations and XPS. Finally, RH-CIIP was able to remove almost 99 % Cu2+ in lake water samples that satisfied the drink water standard. [ABSTRACT FROM AUTHOR]

The development of highly efficient adsorptive material for the selective capture of Pd(II), and re-utilization of spent Pd(II)-loaded adsorbent as an efficient catalyst for organic synthesis are of great significance, but challenging. Particularly, the heterogeneous palladium-catalyzed Suzuki reaction in aqueous media is much more challenging than that of homogeneous. Herein, several novel Pd(II) ion-imprinted polymers (PIIPs) based on dendritic fibrous silica particles are constructed by surface ion imprinting technology (SIIT), using Schiff base and pyridine groups functionalized organosilicon as functional monomer. The PIIP-3 prepared by 3 g of functional monomer exhibits the best adsorption performance, and shows ultrafast (10 min) and selective capture of Pd(II) with high uptake capacity (382.5 mg/g). Moreover, the waste Pd(II) loaded PIIP-3 (PIIP-3-Pd) can serve as a catalyst towards the Suzuki reaction in water, affording 94.2 % yield of the desired product. Interestingly, the PIIP-3-Pd can be reused 12 times without an appreciable decrease in catalytic activity, which is probably due to the imprinted cavity and specific recognition site of PIIP-3 can match and recapture Pd active species in a complex catalytic environment. Thus, this work demonstrates huge potentials of SIIT to enhance the selectivity of adsorption process and increase the lifetime of catalysts. [Display omitted] • A new ion-imprinted polymer was developed using DFSPs as the carrier. • The PIIP-3 exhibited ultrafast, excellent and selective adsorption for Pd(II). • The waste PIIP-3-Pd could be used as a reusable and heterogeneous catalyst. [ABSTRACT FROM AUTHOR]

Three heterotopic ligands L1, L2, and L3have been prepared by the reaction of 4,4′-bis(bromomethyl)-2,2′-bipyridine with 4,5-diazafluoren-9-oxime, 9-(2-hydroxy)phenylimino-4,5-diazafluorene, and 9-(4-hydroxy)phenylimino-4,5-diazafluorene, respectively, in DMF. The three ligands consist of two 4,5-diazafluorene units and one 2,2′-bipyridine unit. Ru(II) complexes [{Ru(bpy)2}3(μ3-L1−3)](PF6)6(bpy = 2,2′-bipyridine) were prepared by refluxing Ru(bpy)2Cl2·2H2O and the ligands in 2-methoxyethanol. The three Ru(II) complexes display metal-to-ligand charge-transfer absorption at 445–450 nm and one Ru(II)-centered oxidation at 1.32 V in CH3CN solution at room temperature. Upon excitation into the metal-to-ligand charge-transfer band, the emission intensities of [{Ru(bpy)2}3(μ3-L2)]6+and [{Ru(bpy)2}3(μ3-L3)]6+are almost equal to that of [{Ru(bpy)2}3(μ3-L1)]6+in CH3CN solution at room temperature, but weaker than that of [{Ru(bpy)2}3(μ3-L1)]6+in EtOH–MeOH (4 : 1, v/v) glassy matrix at 77 K. [ABSTRACT FROM PUBLISHER]

With the deepening of the concept of recycling economy and green chemistry, selective capture of Cu(II) from wastewater by biosorbent and reuse of the spent Cu(II)-loaded adsorbent are of great significance. Herein, we synthesized composite of rice husk (RH) with mesoporous silica MCM-41 (RH@MCM-41) modified by organosilane containing amino and schiff groups as functional monomer and cross-linking agent. The silica modified RH@MCM-41 was employed as supporter to fabricate copper ion-imprinted polymers as absorbents (named as RM-CIIPs) via surface ion imprinting technique. Adsorption isotherms, kinetics, selectivity and mechanism of RM-CIIPs to remove Cu(II) were investigated with respect to different adsorption condition. Furthermore, we explored the catalytic activity of spent Cu(II)-loaded adsorbent in Glaser coupling reaction. Batch adsorption studies revealed that RM-CIIP-3 prepared with functional monomer shows the best adsorption capacity (91.4 mg/g) for Cu(II), and adsorption equilibrium could be reached within 30 min. RM-CIIP-3 exhibited an excellent selectivity for capturing Cu(II) and reusability in six adsorption/desorption cycles. More importantly, the spent Cu(II)-loaded adsorbent could be used as bio-heterogeneous catalyst and afford the desired product (1,4-diphenylbutadiyne) in 99.1% yield. Our research indicates an eco-friendly systematic strategy to utilize the waste material as an adsorbent for removing heavy metals and catalyst for industry. [Display omitted] • The rice husk-based ion imprinted polymer adsorbent was developed. • The RM-CIIP-3 exhibits excellent adsorption capacity and selectivity for Cu(II). • The OCASBG was employed as functional monomer and cross-linking agent. • RM-CIIP-3-Cu was first time used as a bio-heterogeneous catalyst in Glaser coupling. [ABSTRACT FROM AUTHOR]

With the deepening of the concept of recycling economy and green chemistry, selective capture of Cu(II) from wastewater by biosorbent and reuse of the spent Cu(II)-loaded adsorbent are of great significance. Herein, we synthesized composite of rice husk (RH) with mesoporous silica MCM-41 (RH@MCM-41) modified by organosilane containing amino and schiff groups as functional monomer and cross-linking agent. The silica modified RH@MCM-41 was employed as supporter to fabricate copper ion-imprinted polymers as absorbents (named as RM-CIIPs) via surface ion imprinting technique. Adsorption isotherms, kinetics, selectivity and mechanism of RM-CIIPs to remove Cu(II) were investigated with respect to different adsorption condition. Furthermore, we explored the catalytic activity of spent Cu(II)-loaded adsorbent in Glaser coupling reaction. Batch adsorption studies revealed that RM-CIIP-3 prepared with functional monomer shows the best adsorption capacity (91.4 mg/g) for Cu(II), and adsorption equilibrium could be reached within 30 min. RM-CIIP-3 exhibited an excellent selectivity for capturing Cu(II) and reusability in six adsorption/desorption cycles. More importantly, the spent Cu(II)-loaded adsorbent could be used as bio-heterogeneous catalyst and afford the desired product (1,4-diphenylbutadiyne) in 99.1% yield. Our research indicates an eco-friendly systematic strategy to utilize the waste material as an adsorbent for removing heavy metals and catalyst for industry. [Display omitted] • The rice husk-based ion imprinted polymer adsorbent was developed. • The RM-CIIP-3 exhibits excellent adsorption capacity and selectivity for Cu(II). • The OCASBG was employed as functional monomer and cross-linking agent. • RM-CIIP-3-Cu was first time used as a bio-heterogeneous catalyst in Glaser coupling. [ABSTRACT FROM AUTHOR]

Abstract: The reactions of NbS+ (3∑−, 1Γ) with COS have been studied using density functional theory at the B3LYP level: the O/S exchange reaction (NbS+ +COS→NbO+ +CS2), the S-transfer reaction (NbS+ +COS→ +CO) and the O-transfer reaction (NbS+ +COS→ONbS+ +CS). The different mechanisms on the triplet and singlet surfaces have been identified. It is found that the S-transfer reaction has two parallel reaction paths (path A and path B) with respective to two isomeric products (-1 and -2), which may account, respectively, for the endothermic and the exothermic features of the product cross-section observed in the experiment. The spin-forbidden reaction NbS+ (3∑−)+COS→ (1-A′)+CO was found to be energetically much more favorable than the spin-allowed reaction NbS+ (3∑−)+COS→ (3-A′)+CO. According to the identified reaction mechanisms, a triplet–singlet surface crossing is suggested. The larger activation barriers (23.7 and 59.5kcal/mol) and the small probability of the formation of the preceding intermediate 3IM1 result in a much lower efficiency of the O/S exchange reaction and the O-transfer reaction of the 3∑− ground state of NbS+ with COS. For the O-transfer reaction, a triplet–singlet surface crossing may also exist. [Copyright &y& Elsevier]

This paper proposes a method to identify the blood of 4 poultry species (chicken, duck, goose and pigeon) based on Raman spectroscopy and its baseline. Samples were prepared by pretreatment methods of freezing, thawing, and dilution. The Raman spectra of dynamic blood and static blood were measured, respectively, and the spectral differences between the two research schemes were analyzed. The four species of poultry blood were identified based on the Raman spectroscopy and its baseline. The results show that the method can realize the identification of four species of poultry blood. In addition, the potential of Raman spectroscopy as a technique for determining carotenoids in blood has been clearly confirmed, which opens up the possibility to quickly determine whether poultry eats feed containing carotenoids without sample preparation. [Display omitted] • Identifying the blood of 4 species of poultry based on Raman spectroscopy and baseline. • Detecting the characteristic Raman spectra of carotenoids in chicken blood. • Proposing a new method to analyze feed additives in blood based on Raman spectroscopy. • Comparing the spectral characteristics of static blood and dynamic blood. [ABSTRACT FROM AUTHOR]

Abstract: Three bridging ligands 5,5′-bis[(4,5-diazafluoren-9-ylimino)methyl]-2,2′-bipyridine (L1), 5,5′-bis[2-(4,5-diazafluoren-9-ylimino)phenoxymethyl]-2,2′-bipyridine (L2), 5,5′-bis[4-(4,5-diazafluoren-9-ylimino)phenoxymethyl]-2,2′-bipyridine (L3), and corresponding Ru(II) complexes [(bpy)6Ru3(L1–3)](PF6)6 (bpy=2,2′-bipyridine) have been synthesized. The three ligands have two kinds of nonequivalent chelating sites: one involving the 2,2′-bipyridine moiety, and the other involving the 4,5-diazafluorene moiety. The emission intensities of complexes [(bpy)6Ru3(L2)]6+ and [(bpy)6Ru3(L3)]6+ are almost equal to that of complex [(bpy)6Ru3(L1)]6+ in CH3CN solution at room temperature, but weaker than that of complex [(bpy)6Ru3(L1)]6+ in EtOH–MeOH (4:1, v/v) glassy matrix at 77K. Cyclic voltammetry and differential pulse voltammetry studies of the three complexes show one Ru(II)-centered oxidation at around 1.33V for the RuII/III couple. [Copyright &y& Elsevier]

Abstract: Uniform and monodispersed TiO2 hollow spheres with nanoporous titania shell are prepared successfully by using carboxyl-functionalized polystyrene spheres as templates. The results show that TiO2 hollow spheres pose a stable reversible capacity of 230 mAhg−1 at 33.5 mAg−1 and 120 mAhg−1 at 1675 mAg−1, which are higher than that of bulk TiO2 with coarse grain. The discharge process of TiO2 hollow spheres are suggested containing three consecutive stages: the formation of tetragonal Li x TiO2 solid solution, coexistence of two-phase mixture of Li0.05TiO2 and Li0.5TiO2 at 1.75 V and additional lithium storage in the surface. The superior high rate and high capacity performance of prepared TiO2 hollow spheres are due to its highly reversible additional surface capacities and accommodation of phase transformation within nanostructure. [Copyright &y& Elsevier]

Abstract: The reaction mechanism of the Mn+ (7 S and 5 S states) with COS has been studied by means of density functional method (B3LYP). The overall energetics has been refined at the CCSD (T) level. The calculated results indicate that both the C–S and C–O bond activations proceed via an insertion–elimination mechanism. The C–S bond activation is found to be much more favorable than the C–O bond activation. Intersystem crossing between the septuplet and quintet surfaces may occur along both the C–O and C–S bond activation branches. The calculated barriers of spin-forbidden reaction Mn+ (7 S)+COS→MnS+ (5 Π)+CO and spin-allowed reaction Mn+ (7 S)+COS→MnS+ (7 Π)+CO are 17.6 and 43.8kcal/mol, respectively, which are in good agreement with the values assigned in the experiment. [Copyright &y& Elsevier]

A novel ruthenium(II) polypyridyl complex bearing 1,8-naphthyridine was successfully designed and synthesized. This complex was fully characterized by EI-HRMS, NMR, and elemental analyses. The recognition properties of the complex for various metal ions were investigated. The results suggested that the complex displayed high selectivity and sensitivity for Cu2+ and Fe3+ ions with good anti-interference in the CH3CN/H2O (1:1, v/v) solution. The fluorescent chemosensor showed obvious fluorescence quenching when the Cu2+ and Fe3+ ions were added. The detection limits of Cu2+ and Fe3+ were 39.9 nmol/L and 6.68 nmol/L, respectively. This study suggested that this Ru(II) polypyridyl complex can be used as a high selectivity and sensitivity fluorescent chemosensor for Cu2+ and Fe3+ ions. [ABSTRACT FROM AUTHOR]