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The Yao silkworm is a unique silkworm resource producing yellow flat plate silk that has only been reared by the Baiku Yao ethnic group in Nandan County, Guangxi Province, China for a thousand years. Here, we report the mitochondrial genomes (mitogenomes) of five Yao silkworm strains and 10 local Guangxi strains of the domestic silkworm (Bombyx mori) L. (Lepidoptera: Bombycidae), and use the resulting mitogenomes and the available Bombyx mitogenomes to characterize their genome architecture and trace the evolutionary origin of the Yao silkworm. The five Yao silkworm mitogenomes exhibited genome architectures identical to typical set of 37 mitochondrial genes (13 protein-coding genes, 22 transfer RNAs, and two ribosomal RNAs) and a high level of genome sequence similarity with the domestic silkworm. Mitogenome-based phylogenetic reconstruction provided solid evidence that the Yao silkworm shares a common ancestor with the domestic silkworm. Sliding window analysis uncovered a distinct variation pattern in the mitogenome between the Yao silkworm and the other domestic silkworm strains. The phylogenetic analyses revealed a basal placement of the Yao silkworm among all available domestic silkworm strains, indicating that the Yao silkworm is an ancient population of the domestic silkworm. Our data indicated that the Yao silkworm (B. mori) is a lineage of the domestic silkworm, which for the first time provides insights into the origin of the Yao silkworm., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America.)

Diapause is an important biological characteristic for many insect species to adapt to adverse environmental conditions and maintain the continuity of the race. Compared with the traditional hydrochloric acid or/and cold storage treatment methods, the artificial corona incubation technology of silkworm ( Bombyx mori ) eggs has many advantages including, the absence of pollution, easy operation and safety. However, this technology has not yet been applied in sericulture. In this study, we developed a novel artificial corona instrument to successfully disrupt the diapause of newly laid and refrigerated eggs from various Chinese and Japanese lineage silkworm strains. Subsequently, we invented a very early corona treatment (VECT) strategy to prevent the diapause of newly laid silkworm eggs within 4 h of oviposition. The hatching rates of the larvae were more than 95% in all diapause silkworm strains, which was comparable to the effect of the traditional HCl treatment strategy. In addition, we developed a combination strategy of VECT and pre-blastoderm microinjection and successfully created transgenic silkworms in various diapause strains. The results of the current study can aid in improving the corona artificial incubation technology and promote its application in sericulture., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhang, Huang, Wang, Li, Bi, Zhao, Xiang and Long.)

Here, we describe the first complete mitochondrial genome of Yao silkworm, a unique silkworm resource native at Guangxi, China. This circular molecule is 15,656 bp long and contains the typical set of 37 genes (13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes) and one non-coding A + T-rich region of 494 bp long. The genome organization and gene arrangement are identical to those observed in all available Bombyx mori strains. The phylogenetic tree inferred from Bayesian inference provides a molecular evidence that Yao silkworm belongs to the domestic silkworm ( B. mori ), rather than a novel silkworm species., Competing Interests: The authors declare no competing financial interest. The authors alone are responsible for the content and writing of the paper., (© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Background: Inflammatory bowel disease (IBD) is characterized by disturbance of pro-inflammatory cytokines and anti-inflammatory cytokines. Previous studies have demonstrated the effect of anti-inflammatory cytokines, such as interleukin-10 (IL-10) or IL-4 on IBD, but their data were controversial. This study further investigated the effect of IL-4 (IL-4), IL-10 and their combination on treatment of trinitrobenzenesulfonic acid (TNBS)-induced murine colitis., Methods: pcDNA3.0 carrying murine IL-4 or IL-10 cDNA was encapsulated with LipofectAMINE 2000 and intraperitoneally injected into mice with TNBS-induced colitis. The levels of intestinal IL-4 and IL-10 mRNA were confirmed by quantitative-RT-PCR. Inflamed tissues were assessed by histology and expression of interferon (IFN)-γ, tumor necrosis factor (TNF)-α and IL-6., Results: The data confirmed that IL-4 or IL-10 over-expression was successfully induced in murine colon tissues after intraperitoneal injection. Injections of IL-4 or IL-10 significantly inhibited TNBS-induced colon tissue damage, disease activity index (DAI) and body weight loss compared to the control mice. Furthermore, expression of IFN-γ, TNF-α and IL-6 was markedly blocked by injections of IL-4 or IL-10 plasmid. However, there was less therapeutic effect in mice injected with the combination of IL-4 and IL-10., Conclusions: These data suggest that intraperitoneal injection of IL-4 or IL-10 plasmid was a potential strategy in control of TNBS-induced murine colitis, but their combination had less effect.

Thymine, being one of the four nucleobases in the nucleic acid of DNA, has received an increasing interest due to its potential importance in genetics and possible applications in medical science. In the present study, adsorption of thymine on laser-ablated silver island films was comparatively analyzed by means of surface-enhanced Raman scattering (SERS) and surface-enhanced infrared absorption (SEIRA). Two new bands at 1305 and 1573 cm(-1) appeared in the SERS spectrum of thymine on silver island films and represented that the molecule configuration of thymine hydrolyzed ion compound changed its structure from a keto form to an enol one. The greater enhancements of in-plane ring breath vibration bands and of 1649 cm(-1) band associated with C(4)==O stretching vibration clearly suggested that the thymine molecules were adsorbed on the silver surface via O(8). The interaction of N(3) with silver surface could be inferred by the emergence of a stronger peak at 773 cm(-1), which was assigned to the ring breath caused by the stretching vibration of the C(6)--N(3)--C(2). The blue shift of ring breath vibration from 749 to 773 cm(-1) indicated that thymine ring should have some weak interaction with silver surface, i.e., there was a certain angle between the thymine ring and the silver surface. To sum up, the SERS spectrum indicated that thymine adsorbed on the silver surface as enolate through the O(8) and N(3) atoms. The molecular plane assumed a tilted orientation with respect to the silver surface. Laser-ablated silver island films also exhibited a good surface enhancement to infrared absorption for thymine. Enhancement factor was estimated to be about 200 under our experimental condition. There was no shift of C(2)==O stretching vibration in SEIRA spectrum, revealing that O(7) was not involved in the adsorption process. Consistent with our SERS spectrum, the greater enhancement of the thymine ring deformation vibration (1730 cm(-1)) in SEIRA agreed a tilted orientation of thymine on silver surface.

In this paper, we attempt to construct a simple and sensitive detection method for hydrogen peroxide based on reversible colour change and luminescence switching modulated by the electrochemical stimulation and redox reaction of H(2)O(2) with electroreduced polyoxometalate. This method successfully combines the electrochromic and luminescent properties of the polyoxometalate to develop a novel detection method for H(2)O(2) with good reversibility, which displays high sensitivity, a wide linear range and a low detection limit to H(2)O(2).

We selected a Eu(3+)-containing tungstogermanate [(CH(3))(4)N](2.5)H(7.5)[Eu(GeW(11)O(39))(H(2)O)(2)](2)·4.5H(2)O (EuGeW) as a molecular dyad combining fluorescence and electroactivity components within the same framework and studied its electroswitchable fluorescence in solution and in the thin-film, which can be reversibly switched by electrochemical stimulation.

A novel surfactant-encapsulated organic-inorganic hybrid compound (DODA)(24)Li[Cu(20)Cl(OH)(24)(P(8)W(48)O(184))] x 18 H(2)O (DODA-Cu20) has been prepared from the wheel-shaped tungstophosphate salt K(12)Li(13)[Cu(20)Cl(OH)(24)(H(2)O)(12)(P(8)W(48)O(184))] x 22 H(2)O (Cu20) and dimethyldioctadecylammonium bromide (DODA), and it has been characterized by elemental analysis (EA), thermogravimetric analysis (TGA), (1)H NMR, Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) measurements. Monolayer and multilayer films of DODA-Cu20 were fabricated on different substrates by the Langmuir-Blodgett (LB) technique using H(2)O as the subphase. Another type of organic-inorganic hybrid film, DODA/Cu20, was also deposited on the same substrates as used for the film containing DODA-Cu20 under the same conditions by the LB technique using a Cu20 aqueous solution as the subphase and DODA as the cationic amphiphile for comparison. Both thus-prepared organic-inorganic hybrid films were characterized by UV-vis spectroscopy, XRD, transmission and polarized FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The results indicate that stable monolayers at the air-water interface for DODA-Cu20 and at the air-Cu20 solution interface for DODA can be formed and that two LB films containing DODA-Cu20 and DODA/Cu20 constructed by two different methods both exhibit well-ordered lamellar structures. It is proposed that Cu20 exhibits different packing modes in the two LB films depending on the deposition strategy used.

The reaction of [Ru(arene)Cl(2)](2) (arene = benzene, p-cymene) with [X(2)W(22)O(74)(OH)(2)](12-) (X = Sb(III), Bi(III)) in buffer medium resulted in four organo-ruthenium supported heteropolytungstates, [Sb(2)W(20)O(70)(RuC(6)H(6))(2)](10-) (1), [Bi(2)W(20)O(70)(RuC(6)H(6))(2)](10-) (2), [Sb(2)W(20)O(70)(RuC(10)H(14))(2)](10-) (3), and [Bi(2)W(20)O(70)(RuC(10)H(14))(2)](10-) (4), which have been characterized in solution by multinuclear ((183)W, (13)C, (1)H) NMR, UV-vis spectroscopy, electrochemistry, and in the solid state by single-crystal X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and elemental analysis. Polyanions 1, 2, and 4 crystallize in the triclinic system, space group P1 with the following unit cell parameters: K(5)Na(5)[Sb(2)W(20)O(70)(RuC(6)H(6))(2)] x 22 H(2)O (KNa-1), a = 12.1625(2) A, b = 13.1677(2) A, c = 16.0141(3) A, alpha = 78.9201(7) degrees, beta = 74.4442(8) degrees, gamma = 78.9019(8) degrees, and Z = 1; Cs(2)Na(8)[Bi(2)W(20)O(70)(RuC(6)H(6))(2)] x 30 H(2)O (CsNa-2), a = 11.6353(7) A, b = 13.3638(7) A, c = 16.7067(8) A, alpha = 79.568(2) degrees, beta = 71.103(2) degrees, gamma = 80.331(2) degrees, and Z = 1; Na(10)[Bi(2)W(20)O(70)(RuC(10)H(14))(2)].35H(2)O (Na-4), a = 15.7376(12) A, b = 15.9806(13) A, c = 24.2909(19) A, alpha = 92.109(4) degrees, beta = 101.354(4) degrees, gamma = 97.365(3) degrees, and Z = 2. Polyanions 1-4 consist of two (L)Ru(2+) (L = benzene or p-cymene) units linked to a [X(2)W(20)O(70)](14-) (X = Sb(III), Bi(III)) fragment via Ru-O(W) bonds resulting in an assembly with idealized C(2h) symmetry. Polyanions 1-4 are stable in solution as indicated by the expected (183)W, (13)C, and (1)H NMR spectra. The electrochemistry of 1-4 is described by considering the reduction and the oxidation processes. The nature of the arene in Ru(arene) has practically no influence on the formal potentials of the W-centers, which are more sensitive to the Sb or Bi hetero atoms. The results suggest that the respective Sb- and Bi derivatives have very different pK(a) values, with the reduced form of 1 being the most basic, thus permitting the observation of two well-developed voltammetric waves at pH 6. In contrast, the identity of the arene influences the oxidation processes, thus permitting to distinguish them. A strong electrocatalytic water oxidation peak is observed that is more positive than the one corresponding to the Ru(arene) oxidation process. Also a stepwise oxidation of the Ru(benzene) group could be observed at pH 3. The catalytic efficiency, on the other hand, of 1-4 toward the oxidation of n-hexadecane and p-xylene illustrated the effect of ruthenium substitution on the polyanion catalytic performance.

The reaction between [XW(9)O(34)](9-) (X = As, P) and [RuC(6)H(6)Cl(2)](2) in aqueous buffer solution (pH 6.0) leads to the isolation of two pseudo-sandwich-type heteropolytungstates KNa(6)[(RuC(6)H(6))AsW(9)O(34)] x 17 H(2)O (As-1) and Na(7)[(RuC(6)H(6))PW(9)O(34)] x 14 H(2)O (P-2). Single-crystal X-ray diffraction analyses reveal that the two compounds have the following features: (1) in two polyanions [(RuC(6)H(6))XW(9)O(34)](7-) (X = As, 1; P, 2), the (RuC(6)H(6)) unit is linked via three Ru-O(W) bridges to the side of the trilacunary polyanion, while the lacunary site is still free; (2) the units 1 and 2 are connected exclusively by a central Na cation cluster to form the pseudo-sandwich-type heteropolytungstates; and (3) the pseudo-sandwich-type heteropolytungstates are further connected by Na or K cations to construct the 2D and 3D structures. Furthermore, the electrochemical behaviours of As-1 and P-2 in aqueous solution (1.0 M LiCl + HCl, pH 3.0) have been investigated. Two compounds exhibit the expected reduction processes of the W atoms in a negative potential range and the oxidation of the Ru center in a positive potential range. The results of the electrocatalytic experiments reveal that the compound P-2 has electrocatalytic activity towards the reduction of nitrate.

The tetrairon(III)-substituted polytungstates [Fe(4)(H(2)O)(10)(beta-XW(9)O(33))(2)](n-) (n = 6, X = As(III), Sb(III); n = 4, X = Se(IV), Te(IV)) were immobilized on (3-aminopropyl)triethoxysilane-modified SBA-15 and showed an excellent catalytic performance for solvent-free aerobic oxidation of long-chain n-alkanes using air as the oxidant under ambient conditions through a classical free-radical chain autoxidation mechanism.

Background: Congenital heart disease (CHD) is the most common congenital disorder at birth. Yagel and colleagues's method of heart examination has been proved valuable in finding CHD prenatally in single pregnancies. The aim of this study was to analyze the frequency of CHD in twin pregnancies and the sensitivity of the method., Methods: A total of 1103 pregnant women with twins were enrolled in this study, including 127 cases with high-risk for CHD. Five transverse ultrasound measurements were used for fetal heart examination, including the upper abdomen view, four-chamber view, five-chamber view, pulmonary artery bifurcation view, and three-vessel view. In the fetuses who were diagnosed with CHD and whose parents requested termination of the pregnancy, autopsy of the fetal heart was performed after an abortion, and a blood sample was collected from the heart for chromosome evaluation. In the other fetuses, a close follow-up was conducted by echocardiography within one year after birth., Results: Antenatally, CHD was found in 12 twins, of which 4 were from the high-risk group (3.15%), and 8 from the low-risk group (0.82%). In 2 pairs of the twins, the two fetuses had a same kind of CHD (one pair had tetralogy of Fallot (TOF), another pair had rhabdomyoma). Another pair had different types of anomaly (one fetus had TOF, and the other duodenal atresia with a normal heart). Termination of pregnancy was performed in these three pairs and the autopsy of the fetal heart confirmed the ultrasound findings. In the other 9 pairs, CHD was detected in one fetus, and a normal heart in the others. In the cases who received chromosome evaluation, 2 had abnormal chromosomes. During the follow-up after birth, heart examinations confirmed the prenatal diagnosis in 7 of the 9. The diagnosis of CHD was missed antenatally in 2 pairs of twins. In both the cases, one fetus was normal, and the other was confirmed as having CHD after birth (small ventricle septum defect in one, and persistent open ductus arteriosus in the other). Thus, the total frequency of CHD was 16 (7.3/1000), which was similar to that in single pregnancies. The sensitivity of fetal echocardiography was 87.5% and the specificity was 100%., Conclusions: The frequency of CHD is the same in twin as in single pregnancies. Systemic ultrasound scanning with five transverse views is effective in diagnosing fetal CHD in twin pregnancies.

Objective: To investigate the value and clinical significance of congenital heart diseases (CHD) detection in twins., Methods: A total of 1103 twins were included in this study (127 twins were at high risk for CHD). The fetal hearts were scanned by ultrasound using Yagel's heart examination method. Autopsies were done when the pregnancy was terminated. And blood samples from fetal hearts or umbilical veins were used to evaluate fetal chromosomes. A close follow-up was conducted for normal heart cases and another heart examination was done within three months after birth., Results: (1) 12 twins (1.09%, 12/1103) had CHD. Among them, 4 cases were from the high risk for CHD group (33.3%, 4/12), and 8 cases (66.7%, 8/12) were from the low risk pregnancy group. (2) Two twins suffered from the same CHD (one pair were both TOF, and the other pair were both rhabdomyoma). One pair of twins had different abnormalities (one baby was TOF, and the other was duodenal atresia with a normal heart). All three pairs of twins chose termination and autopsies were conducted. Unanimous conclusions between prenatal ultrasound and autopsy were obtained. Nine twins were CHD in one baby and a normal heart in the other baby. Seven of them had the same conclusion after delivery. (3) Two twins with CHD were found with fetal abnormal chromosome. (4) 1091 cases were not found having any abnormality, however, one fetus from one twin pair was diagnosed with ventricular septal defect (VSD) with abnormal chromosome after birth, and one fetus from another twin pair had patency of ductus arteriosus after birth. (5) The sensitivity of Yagel's heart examination was 82.4% and specificity was 100% in twins., Conclusion: Yagel's heart examination is an effective and time-saving method to scan fetal hearts in twins.

The benzene-Ru(II)-supported dilacunary decatungstosilicate [{Ru(C6H6)(H2O)}{Ru(C6H6)}(gamma-SiW10O36)]4- and the isostructural decatungstogermanate [{Ru(C6H6)(H2O)}{Ru(C6H6)}(gamma-GeW10O36)]4- have been synthesized and characterized by multinuclear solution NMR, IR, elemental analysis, and electrochemistry. Single-crystal X-ray analysis was carried out on K4[{Ru(C6H6)(H2O)}{Ru(C6H6)}(gamma-SiW10O36)].9H2O (K-1), which crystallizes in the orthorhombic system, space group Pmn2(1), with a = 13.6702(3) A, b = 16.2419(4) A, c = 12.1397(2) A, and Z = 2, and on K4[{Ru(C6H6)(H2O)}{Ru(C6H6)}(gamma-GeW10O36)].7H2O (K-2), which also crystallizes in the orthorhombic system, space group Pmn2(1), with a = 13.6684(12) A, b = 16.297(2) A, c = 12.1607(13) A, and Z = 2. Polyanions 1 and 2 consist of a Ru(C6H6)(H2O) group and a Ru(C6H6) group linked to a dilacunary (gamma-XW10O36) Keggin fragment resulting in an assembly with idealized Cs symmetry. The Ru(C6H6)(H2O) group is bound at the lacunary polyanion site via two Ru-O(W) bonds, whereas the Ru(C6H6) group is bound on the side via three Ru-O(W) bonds. Polyanions 1 and 2 were synthesized in aqueous acidic medium at pH 2.5 by the reaction of [Ru(C6H6)Cl2]2 with [gamma-SiW10O36]8- and [gamma-GeW10O36]8-, respectively. The formal potentials are roughly the same for the first W waves of 1 and 2. However, important differences appear for the second W waves. These observations indicate different acid-base properties for the reduced forms of 1 and 2. Three oxidation processes were detected: the oxidation of the Ru center is followed first by irreversible electrocatalytic processes of the Ru-benzene moiety and then of the electrolyte. Comparison of this behavior with that of the precursor reagent, [Ru(C6H6)Cl2]2, was useful to understand the main oxidation processes. A ligand substitution reaction was observed upon addition of dimethyl sulfoxide (dmso) to 1, 2, or [Ru(C6H6)Cl2]2. This reaction facilitates substantially the oxidation of the Ru center. The dmso was oxidized with large electrocatalytic currents more efficiently in the presence of 1 and 2 than with [Ru(C6H6)Cl2]2.

The dimeric, pentacopper(II)-substituted tungstosilicate [Cu(5)(OH)(4)(H(2)O)(2)(A-alpha-SiW(9)O(33))(2)](10)(-) (1) has been characterized by single-crystal X-ray diffraction, elemental analysis, IR, electrochemistry, magnetic measurements, electron paramagnetic resonance (EPR), and mass spectrometry (MS). Magnetization and high-field EPR measurements reveal that the pentameric copper core {Cu(5)(OH)(4)(H(2)O)(2)}(6+) of 1 exhibits strong antiferromagnetic interactions (J(a) = -51 +/- 6 cm(-)(1), J(b) = -104 +/- 1 cm(-)(1), and J(c) = -55 +/- 3 cm(-)(1)) resulting in a spin S(T) = (1)/(2) ground state. EPR data show that the unpaired electron spin density is localized on the spin-frustrated apical Cu(2+) ion with g(zz) = 2.4073 +/- 0.0005, g(yy) = 2.0672 +/- 0.0005, g(xx) = 2.0240 +/- 0.0005, and A(zz) = -340 +/- 20 MHz (-0.0113 cm(-)(1)). 1 can therefore be considered as a model system for a five-spin, electronically coupled, spin-frustrated system. Polyanion 1, which is stable over a wide pH domain (pH 1-7), was characterized by cyclic voltammetry (CV) in a pH 5 medium. Its CV was constituted by an initial two-step reduction of the Cu(2+) centers to Cu(0) through Cu(+), followed at more negative potential by the redox processes of the W centers. Controlled potential coulometry of 1 allows for the reduction of the five Cu(2+) centers, as seen by consumption of 10.05 +/- 0.05 electrons per molecule. Polyanion 1 triggers efficiently the electrocatalytic reduction of nitrate and nitrite, and it also catalyzes the reduction of N(2)O. To our knowledge, this is the first example of N(2)O catalytic reduction by a polyoxoanion. Fourier transform ion cyclotron resonance MS was used to unambiguously assign the molecular weight of the solution-phase species 1 and the oxidation states of the Cu atoms in the central {Cu(5)(OH)(4)(H(2)O)(2)}(6+) core. Infrared (IR) multiphoton dissociation MS/MS of 1 showed evidence of a condensation process similar to bronze formation at low irradiation intensity. Higher IR intensity resulted in the formation of stable fragments consistent with those previously observed in the solution chemistry of polyoxoanions.

The benzene-Ru(II)-supported trilacunary heteropolytungstates [(RuC6H6)2XW9O34]6- (X = Si, 1; Ge, 2) have been synthesized and characterized by multinuclear solution NMR (183W, 13C, 1H, 29Si), UV-vis and IR spectroscopy, electrochemistry, and elemental analysis. Single-crystal X-ray analysis was carried out on Rb2Na4[(RuC6H6)2SiW9O34].21H2O (RbNa-1), which crystallizes in the triclinic system, space group P, with a = 11.9415(2) A, b = 13.3123(2) A, c = 19.4927(4) A, alpha = 96.6460(10) degrees , beta = 95.1570(10) degrees , gamma = 98.2560(10) degrees , and Z = 2 and on Cs2Na4[(RuC6H6)2GeW9O34].19.5H2O (CsNa-2), which crystallizes also in the triclinic system, space group P, with a = 11.930(4) A, b = 13.353(4) A, c = 19.586(6) A, alpha = 95.982(5) degrees , beta = 95.414(6) degrees , gamma = 98.142(5) degrees , and Z = 2. The novel polyanion structure consists of two (RuC6H6) units linked to a trilacunary (XW9O34) Keggin fragment via Ru-O(W) and Ru-O(X) bonds resulting in an assembly with Cs symmetry. Polyanions 1 and 2 were synthesized by reaction of [RuC6H6Cl2]2 with [A-alpha-XW9O34]10- in aqueous buffer medium (pH 6.0). Both 1 and 2 are stable in solution as indicated by the expected 5-line pattern (2:1:2:2:2) in the 183W NMR and the expected (3C, 1H, and 29Si spectra. Descriptions of the respective electrochemical behaviors of the W centers and the Ru centers in 1 and 2 are given in media where these processes are clearly defined. In a pH = 3 acetate medium, the cyclic voltammetry of the W centers shows the known fingerprint of the trilacunary alpha-[XW9O34]n- (X = Ge, Si) moieties. The presence of the (RuC6H6) substituents imparts a good stability to these fragments in solution. Stepwise oxidation of the Ru centers was suspected in pH = 5 acetate medium, but only the first step was well-separated from a large current composite wave. The stepwise oxidation was finally observed clearly in a DMF-water (90/10 v/v) mixture and shows two well-behaved Ru oxidation processes. A short comparison is made with DMSO-bearing Ru polyoxometalates.

The ruthenium(II)-supported heteropolyanions [HXW7O28Ru(dmso)3]6-(X=P, 1; As, 2) are composed of a Ru(dmso)3 group attached to an unprecedented heptatungstate fragment via two Ru-O-W bonds and one Ru-O-X bond, which represents a fundamentally novel mode of Ru-coordination to a polyoxoanion framework. Multinuclear 183W, 31P, 13C, and 1H NMR studies indicate high stability of 1 and 2 in solution.

The iron(III)-substituted tungstogermanate [Fe6(OH)3(A-alpha-GeWO34(OH)3)2]11- (1) has been synthesized and characterized by IR, elemental analysis, SQUID magnetometry, electron paramagnetic resonance (EPR), and electrochemistry. Single-crystal X-ray analysis was carried out on Cs4Na7[Fe6(OH)3(A-alpha-GeW9O34(OH)3)2] x 30H2O, which crystallizes in the monoclinic system, space group C2/m, with a = 36.981(4) A, b = 16.5759(15) A, c = 16.0678(15) A, beta = 95.311(3) degrees, and Z = 4. Polyanion 1 consists of two (A-alpha-GeW9O34) Keggin moieties linked via six Fe3+ ions, leading to a double-sandwich structure. The equivalent iron centers represent a trigonal prismatic Fe6 fragment, resulting in virtual D3h symmetry for 1. Electrochemistry studies revealed that 1 is stable in solution from pH 3 to at least pH 7. In pH = 3 media the reduction of the six Fe3+ centers was featured by a single voltammetric wave for most supporting electrolytes used. In that case, whatever the scan rate from 1000 mV x s(-1) down to 2 mV x s(-1), no splitting of the single Fe-wave of 1 was observed. The acetate medium induced a partial splitting of the wave, and this separation is enhanced with increasing pH. Remarkable efficiency of 1 in the electrocatalytic reduction of nitrite, nitric oxide, and nitrate is demonstrated. Magnetic susceptibility (chi) measurements indicate a diamagnetic (S(T) = 0) ground state, with an average J = -12 cm(-1) and g = 2.00. EPR studies confirm that the ground state is indeed diamagnetic, since the EPR signal intensity steadily decreases without any line broadening as the temperature is lowered and becomes unobservable below about 50 K. The signal is a single broad peak at all frequencies (90-370 GHz), ascribed to the thermally accessible excited states. Its g(iso) is 1.992 51, as expected for a high-spin Fe3+-containing species, and supports the chi data analysis.

The palladium(II)-substituted tungstosilicate [Cs(2)K(H(2)O)(7)Pd(2)WO(H(2)O)(A-alpha-SiW(9)O(34))(2)](9)(-) (1) has been synthesized and characterized by IR, elemental analysis, and electrochemistry. Single-crystal X-ray analysis was carried out on Cs(3)K(2)Na(4)[Cs(2)K(H(2)O)(7)Pd(2)WO(H(2)O)(A-alpha-SiW(9)O(34))(2)].5H(2)O (1a), which crystallizes in the monoclinic system, space group P2(1)/n, with a = 16.655(3) A, b = 19.729(4) A, c = 25.995(5) A, beta = 95.46(3) degrees , and Z = 4. Polyanion 1represents the first structurally characterized palladium(II)-substituted tungstosilicate. The title polyanion consists of two (A-alpha-SiW(9)O(34)) Keggin moieties linked via a [WO(H(2)O)](4+) group and two equivalent, square-planar Pd(2+) ions leading to a sandwich-type structure with C(2)(v) symmetry. The central belt of 1 contains also one potassium and two cesium ions. Polyanion 1 was synthesized by reaction of Pd(CH(3)COO)(2) with K(10)[A-alpha-SiW(9)O(34)] in aqueous acidic medium (pH 4.8). A cyclic voltammetry study of polyanion 1 in a pH 5 medium shows a Pd(0) deposition process on the glassy carbon electrode surface. The corresponding wave and that of tungsten redox processes could be separated clearly during the first few runs before their merging into a broad composite wave. The film thickness increases with the number of potential cycles or the duration of potentiostatic electrolysis. As judged from hydrogen sorption/desorption pattern, the quality of the film deposited from polyanion 1 is better than that of a film deposited directly from Pd(2+) solutions.

The dimeric, pentacopper(II) substituted tungstosilicate [Cu(5)(OH)(4)(H(2)O)(2)(A-alpha-SiW(9)O(33))(2)](10-) (1) has been synthesized in good yield using a one-pot procedure by reaction of Cu(2+) ions with the trilacunary precursor salt K(10)[A-alpha-SiW(9)O(34)]. The title polyanion represents the first polyoxotungstate substituted by 5 copper centers and the central copper-hydroxo-aqua fragment is completely unprecedented. In the course of the reaction, two [A-alpha-SiW(9)O(34)](10-) Keggin half-units have fused in an asymmetrical fashion resulting in the lacunary polyoxotungstate [Si(2)W(18)O(66)](16-). The vacancy in this species is stabilized by a magnetic cluster of five octahedrally coordinated Cu(2+) ions resulting in polyanion 1 with C(2v) symmetry.

The novel Ru(II)-supported heteropolytungstates [Ru(dmso)(3)(H(2)O)XW(11)O(39)](6-)(X = Ge, Si) have been synthesized and characterized by single-crystal X-ray diffraction, multinuclear NMR ((183)W, (13)C, (1)H, (29)Si) and IR spectroscopy, elemental analysis and electrochemistry. The novel polyanion structure consists of a Ru(dmso)(3)(H(2)O) unit linked to a monolacunary [XW(11)O(39)](8-) Keggin fragment via two Ru-O-W bonds resulting in an assembly with C(1) symmetry. Polyanions 1 and 2 were synthesized by reaction of cis-Ru(dmso)(4)Cl(2) with [A-alpha-XW(9)O(34)](10-) in aqueous, acidic medium (pH 4.8). Tungsten-183 NMR of 1 leads to a spectrum with 11 peaks of equal intensity, indicating that the solid-state structure is preserved in solution. Electrochemistry studies revealed that 1 and 2 are stable in solution at least from pH 0 to 7, even in the presence of dioxygen. Their cyclic voltammetry patterns show mainly two two-electron reversible W-waves, those of the Si derivative 2 being located at slightly more negative potentials than those of the Ge derivative 1. The observed stability of 1 and 2 might be attributed to a stabilization of the Ru-center both by the strongly bound dmso ligands and the Keggin moiety. This stabilization drives the redox waves of Ru outside the accessible potential range. However, conditions were found to reveal, at least partially, the redox behavior of Ru in 1 and 2.

The palladium-substituted tungstoantimonate(III) [Cs(2)Na(H(2)O)(10)Pd(3)(alpha-SbW(9)O(33))(2)](9-) (1) has been synthesized and characterized by IR, elemental analysis, and electrochemistry. Single-crystal X-ray analysis was carried out on Cs(3)KNa(5)[Cs(2)Na(H(2)O)(10)Pd(3)(SbW(9)O(33))(2)].16.5H(2)O, which crystallizes in the monoclinic system, space group P2(1)/m, with a = 13.3963(13) A, b = 19.5970(19) A, c = 18.1723(17) A, beta = 100.416(2) degrees, and Z = 2. Polyanion 1 represents the first structurally characterized palladium(II)-substituted polyoxometalate. The title polyoxoanion consists of two (alpha-Sb(III)W(9)O(33)) Keggin moieties linked via three Pd(2+) ions leading to a sandwich-type structure. The palladium centers are equivalent, and they are coordinated in a square-planar fashion. The central belt of 1 contains also one sodium and two cesium ions which reduces the symmetry of the polyanion to C(2)(v)(). Polyanion 1 was synthesized in good yield by reaction of Pd(CH(3)COO)(2) with Na(9)[SbW(9)O(33)] in aqueous acidic medium (pH 4.8). A cyclic voltammetry study of polyanion 1 in a pH 5 medium gives essentially the same characteristics as those observed for the deposition of Pd(0) on the glassy carbon electrode surface from Pd(2+) solutions. The film thickness increases with the number of potential cycles or the duration of potentiostatic electrolysis. The particularly sharp hydrogen sorption/desorption pattern indicates the excellent quality of the Pd(0) deposit from polyanion 1.

Both coordination and hydrogen bonds contribute to networking in the supramolecular title compound, [Co(C(6)H(6)NO(3)S)(C(12)H(8)N(2))(H(2)O)(3)]Cl, which contains a discrete [Co(C(6)H(6)NO(3)S)(C(12)H(8)N(2))(H(2)O)(3)](+) complex cation, formed by one 4-aminobenzenesulfonate ligand, one 1,10-phenanthroline ligand and three coordinated water molecules, together with one uncoordinated chloride anion. These discrete cations and chloride anions are connected by hydrogen-bonding interactions into a two-dimensional supramolecular motif. Further hydrogen-bonding interactions consolidate the structural architecture and extend the two-dimensional supramolecular structure into a three-dimensional network.

Six new heteropoly compounds in the [M4(H2O)2(As2W15O56)2]16- series (M = CuII, MnII, CoII, NiII, ZnII, CdII), previously unknown, were synthesized and characterized by means of IR, UV-vis, CV, 183W NMR, TG-DSC, and elemental analyses. The synthetic method used in preparing this type of heteropoly compounds was different from that in preparing the corresponding tungstophosphates in that the starting materials were transition metal chlorides in 1.5 times the stoichiometric amount and the required pH value is lower than 2. The crystal structure of Na16[Cu4(H2O)2(As2W15O56)2].47H2O was solved in triclinic, P1 symmetry, with a = 12.721(3) A, b = 24.516(5) A, c = 26.450(5) A, alpha = 89.90(3) degrees, beta = 77.32(3) degrees, gamma = 89.96(3)degrees, V = 8048(3) A3, Z = 2, and R = 0.0966. This anion is isostructural with the previously reported [Cu4(H2O)2(P2W15O56)2]16-, having a rhombic tetrameric cluster Cu4O16 sandwiched by two trivacant Dawson-Wells anions [As2W15O56]12-. The range of the bond lengths of the equatorial Cu-O bonds is 1.83-2.05 A, while that of the axial Cu-O bonds is 2.30-2.39 A. The distortion of the Cu4O16 cluster is smaller in the As species than in the P species. Two copper atoms in the Cu4O16 cluster are coordinated by water molecules. The replacement reactions of the coordinated water molecules of this series of heteropoly compounds in aqueous solutions and in selected organic solvents are also reported here for the first time. The results show that [Fe(CN)6]4-, [Fe(CN)6]3-, H2NCH2CH2NH2, etc., can replace the coordinated water to form its characteristic color in aqueous solutions, while in organic solvents the coordinated water molecules are lost, leaving unshared coordination positions that can be occupied by some organic ligands such as pyridine, lactic acid, and acetone to restore the octahedral coordination of M2+. The crystallographic morphologies of this series of heteropolyanions after phase transfer are dependent on different transition metal ions present in the central M4O16 clusters although the anions are isostructural with each other.