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In this study, a high-activity Zn–Co double metal cyanide complex was synthesized and used to catalyze the ternary polymerization of carbon dioxide, propylene oxide, and itaconic anhydride to produce a new class of polypropylene carbonates characterized by excellent performance and low ether content. The number average molecular weight of the terpolymer was as high as 2.14 × 105 g·mol−1, and the polydispersity index was as high as 1.58. In the case of PPCIAn3, the 5% weight loss temperature increased by 70°C, the total weight loss temperature increased by 100°C, the tensile strength increased by 6.6 MPa, and the elongation at break decreased to 14.5% with respect to traditional polypropylene carbonate. The apparent efficiency of the catalyst was as high as 45.79 gpolymer/gcatalyst, indicating its high catalytic activity. 1H-NMR spectrometry, gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, and in situ Fourier-transform infrared spectroscopy were used to characterize the polymerization process and the structural properties of the obtained terpolymers.

Time-of-flight (ToF) transient current method is an important technique to study the transport characteristics of semiconductors. Here, both the direct current (DC) and pulsed bias ToF transient current method are employed to investigate the transport properties and electric field distribution inside the MAPbI3 single crystal detector. Owing to the almost homogeneous electric field built inside the detector during pulsed bias ToF measurement, the free hole mobility can be directly calculated to be about 22 cm2⋅V−1⋅s−1, and the hole lifetime is around 6.5 μs–17.5 μs. Hence, the mobility-lifetime product can be derived to be 1.4 × 10−4 cm2⋅V−1–3.9 × 10−4 cm2⋅V−1. The transit time measured under the DC bias deviates with increasing voltage compared with that under the pulsed bias, which arises mainly from the inhomogeneous electric field distribution inside the perovskite. The positive space charge density can then be deduced to increase from 3.1 × 1010 cm−3 to 6.89 × 1010 cm−3 in a bias range of 50 V–150 V. The ToF measurement can provide us with a facile way to accurately measure the transport properties of the perovskite single crystals, and is also helpful in obtaining a rough picture of the internal electric field distribution.

Three complexes [Fe(L)2](ClO4)2 (1)、[Ni(L)2](ClO4)2 (2) and [Co(L)2](ClO4)2 (3) were synthesized by the reaction of N,N’-(4-methylpyridin-2-yl)pyrazine-2,6-diamine (L) with Fe(ClO4)2·6H2O, (Ni(ClO4)2·6H2O or Co(ClO4)2·6H2O) at room temperature, respectively. They were characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. The catalytic behavior of the complexes for the synthesis of propylene carbonate from propylene oxide and carbon dioxide were studied. The results show that all of them showed excellent catalytic activities with TOF as high as 2104 h-1, 2824 h-1 and 2605 h-1, respectively. Complex 2 that exhibit higher catalytic activity was taken to explore the influence of time, pressure and temperature to optimize the reaction condition in detail.

Based on the HMPA ligand, a new air- and moisture-stable pentagonal-bipyramidal DyIII single-ion magnet [Dy(HMPA)2(H2O)5]2·Br6·2HMPA·2H2O (1) was prepared and characterized. Single-crystal X-ray tests showed the two crystallographically independent DyIII ions located in a pentagonal-bipyramidal coordination sphere with strong axial HMPA ligands and weak equatorial water molecules relating to strong unaxial anisotropy. Direct-current and alternating-current magnetic susceptibilities were measured and showed that 1 exhibited slow relaxation of magnetization up to 36 K (1000 Hz) with an energy barrier of 556 K and blocking temperature of 7 K (defined by the peak temperature of zero-field cooling data). The application of a dc field and magnetic dilution were also carried out to explore the existing quantum tunelling of the magnetization process.

By using tripyridyldiamine ligand, N , N’ -di(pyrazin-2-yl)pyridine-2,6-diamine (H 2 dpzpda), linear pentanuclear nickel(II) [Ni 5 (µ 5 -dpzpda) 4 Cl 2 ] (1) and tetranuclear copper(II) [Cu 4 (Hdpzpda) 2 (CH 3 COO) 6 ] (2) complexes were first synthesized and structurally characterized. This pentanickel linear metal chain is helically wrapped by four syn-syn-syn-syn type dpzpda 2- ligands. There are two types of Ni Ni distances existing in the complex. The terminal Ni Ni distances bonded to the axial ligand are longer (2.3877(8) A) affected by the axial ligands. The inner Ni Ni distances are very short and remain constant (2.3071(6) A). Two terminal Ni(II) ions bonded to the axial ligands are in a square-pyramidal (NiN 4 Cl) environment and exhibit long Ni N bonds (2.097(4) A), which are consistent with a high-spin Ni(II) configuration. The inner three Ni(II) ions display short Ni N (1.8915(8)–1.903(4) A) bond distances, which are consistent with a square planar (NiN 4 ), the diamagnetic arrangement of a low-spin Ni(II) configuration. Temperature-dependent magnetic research revealed an antiferromagnetic interaction between the two terminal atoms through a superexchange pathway along metal cores with a parameter of about −51.0 cm –1 . Observation of the first oxidation peak in the cyclic voltammograms of 1 at +1.206 V revealed that this complex is the most resistant to oxidation among all known pentanuclear nickel strings with unmodulated and modulated oligo-α-pyridylamido ligands. The structure of 2 consists of four copper atoms linearly placed with a copper(II) acetate dimer in the centre. In complex 2 ligand H 2 dpzpda coordinates to the Cu(II) atoms as a tetradentate ligand in an all anti conformation. Copper complex 2 is built to a 1-D supramolecular chain structure through intermolecular hydrogen bond and strong π-π interaction (3.19 A) between the pyridine and pyrazine rings. From the magnetic susceptibility data, 2 shows strong antiferromagnetic coupling, which was satisfactorily fitted using Hamiltonian H = J 1 ( S 1 S 2 + S 3 S 4 ) + J 2 S 2 S 3 . The best fitting result were obtained with the parameters J 1 = 10.64 cm −1 , J 2 = −175.36 cm −1 , g = 2.11.

Based on a phosphine oxide ligand, HMPA (hexamethylphosphoric triamide), two mononuclear HoIII-pentagonal bipyramidal complexes were synthesized with the formulas [Ho(HMPA)2(H2O)5]2Cl6·2HMPA·2H2O (1) and [Ho(HMPA)2(H2O)5]Br3·2HMPA (2). Single-crystal X-ray diffraction results show that all HoIII ions in both the two complexes are hepta-coordinated and are located in pentagonal bipyramidal {HoO7} coordination polyhedrons constructed by two axial HMPA ligands and five equatorial water molecules. However, due to the employment of different halide ions as counterions, the second coordination sphere surrounding each [Ho(HMPA)2(H2O)5]3+ moiety is different in the two complexes: in 1, three Cl− ions, one water molecule and one HMPA ligand; in 2, three Br− ions and two HMPA ligands. Ac magnetic susceptibilities under zero dc field show that both the two complexes are single-ion magnets with effective energy barriers of 290 K and 320 K for 1 and 2, respectively. Compared with 1, the enhancement in the energy barrier of 2 is believed to be induced mainly by the change in the second coordination sphere rather than the minor differences in the {HoO7} polyhedrons.

Bladder cancer is the most common malignant tumor of the urinary system. The intention of the present research is to explore the prognostic value and biological function of solute carrier family 12 member 8 (SLC12A8) in bladder cancer. The analysis based on the TCGA and ONCOMINE database revealed that the expression of SLC12A8 in bladder cancer was notably increased compared with the normal group. SLC12A8 expression was notably correlated with the age, pathological stage, T-stage, and lymph node metastasis of bladder cancer patients. Moreover, the patients’ overall survival was notably shorter in the high SLC12A8 group. Compared with the control, SLC12A8 upregulation enhanced the proliferative, invasive, and migratory capacities of bladder cancer cells and promoted the expression of epithelial–mesenchymal transition (EMT) protein markers including β-catenin, vimentin, snail, and slug, while reduced the expression of E-cadherin. In the case of downregulated SLC12A8 expression, the proliferative, invasive, and migratory capacities of bladder cancer cells and the expression of EMT protein markers presented the opposite trend. This study demonstrated that SLC12A8 was highly correlated with oncogenesis and progression of bladder cancer, indicating that SLC12A8 may be a meaningful biomarker for initial diagnosis and early treatment of bladder cancer.

By using tetranaphthyridyl-triamine ligand, N2-(2-(1,8-naphthyridin-7-ylamino)-1,8-naphthyridin-7-yl)-N7-(1,8-naphthyridin-2-yl)-1,8-naphthyridine-2,7-diamine (H3tentra), double-stranded dinuclear helical compounds [M2(H3tentra)2(ClO4)4] [M = NiII (1), CoII (2), FeII (3), ZnII (4)] were synthesized and structurally characterized. The single X-ray crystal structure of iron(II) complex showed that both of H3tentra ligands wrap around the metal–metal axis giving rise to a double-stranded dinuclear helical compound with Fe–Fe separation of ca. 5.326 A. Each ligand uses two nitrogen atoms from two different napthyridine rings, to coordinate one metal centre (Fe or Fe(A)) and therefore, the geometry about the metal ions was described as distorted tetrahedral, with both ligands acting as bisbidentate N4 donors. This distortion is shown by the angles between nitrogen and iron atoms, which range from 80.45(15) to 143.32(14)°. Distorted tetrahedral environment was also proposed for the other complexes on the basis of the magnetic measurements and X-ray results. Strong π–π interactions were observed for all synthesized double stranded helicates of H3tentra ligand. The measured χMT values at 300 K for complexes 2 and 3 found larger than the expected values for two high-spin Co(II) with S = 3/2 and for Fe(II) ions with S = 2 and g = 2, which attributed to the unquenched orbital coupling.

A new Co(II) complex, {[Co(MPA)(4,4′-bpy)(H 2 O)]·2H 2 O} n ( 1 ) (H 2 MPA = 4-methylphthalic acid, 4,4′-bpy = 4,4′-bipyridine), has been prepared under solvothermal condition and fully characterized. The X-ray crystallography test demonstrates that 1 exhibits two-dimensional (2D) layer structure in which the helical Co(II) chains linked by syn-anti carboxylate bridges are connected by 4,4′-bpy ligands. Weak ferromagnetism was observed on direct-current (dc) susceptibility due to the collective effects of the helical chain structure and antiferromagnetic couplings between Co(II) ions transmitted by μ 2 - 1,3-carboxylate groups. Interestingly, slow magnetic relaxation was observed in 1 at liquid helium temperatures without an external dc field.

A series of Salen cobalt complexes have been successfully synthesized and they show high catalytic activity for the copolymerization of propylene oxide (PO) and carbon dioxide (CO2), yielding poly(propylene carbonate) (PPC). After optimizing the reaction conditions such as temperature, pressure and reaction time, the catalytic system achieved excellent conversion (99.47%) and showed high catalytic activity with an initial TOF up to 483.18 h−1. The content of carbonate chain of the PPC and head-to-tail connection are 88.92% and 86.79% respectively. PPC starts to decompose at 230°C and completely decomposed at 260°C. The Mn of the PPC is 109.898 kg/mol, and the PDI is 1.65295.

Through a pyrazine and naphthyridine-containing diamino ligand, N2,N7-di(pyrazin-2-yl)-1,8-naphthyridine-2,7-diamine (H2dpznda), defective extended metal atom chain complexes with one chromium(II) metal absent in centre, [Cr5(μ5-dpznda)4Cl2] (1) and [Cr5(μ5-dpznda)4(NCS)2] (2) were obtained. An electrochemistry research showed that the pentachromium(II) complexes were quite resistant to reduction although accessible to oxidation, with two reversible redox couples at E1/2 = +0.59 and +0.30 V.

Two novel linear hexanuclear nickel complexes [Ni 6 ( μ 6 -dpznda) 4 Cl 2 ](PF 6 ) 2 (1) and [Ni 6 ( μ 6 -dpznda) 4 (NCS) 2 ](PF 6 ) 2 (2) (H 2 dpznda = N 2 , N 7 -di(pyrazin-2-yl)-1,8-naphthyridine-2,7-diamine) were synthesized and structurally characterized. Both the two complexes consist of a linear metal chain and four supporting ligands which are helically wrapped around the metal core. The single crystal X-ray structural analysis showed that the complex 1 belonged to rhombohedral system, space group R -3 with a = b = 34.2051(8), c = 20.7751(5) A, V = 21050.2(9) A 3 and Z = 9. Direct-current magnetic susceptibility measurements showed weak antiferromagnetic interactions with coupling parameters of g = 2.04 and J = −8.27 cm −1 for 1 and g = 2.02 and J = −12.62 cm −1 for 2 , respectively ( Ĥ = –JŜ 1 Ŝ 2 , S 1 = S 2 = 1). The decrease of magnetic moments at low temperature was partly attributed to ZFS. The electrochemical study on complex 1 shows rich features and facility to reduction in its cyclic voltammogram by displaying four reversible redox couples at E 1/2 = +0.01, −0.29, −0.64 and −0.73 V ( vs. Ag/AgCl).

Herein, the excited-state dynamics of an extended metal atom chain complex, Cr3(dpa)4Cl2 (dpa = dipyridylamide), in tetrahydrofuran solution were investigated using femtosecond transient absorption spectroscopy. Upon excitation at a wavelength of 330 nm, two distinct excited-state absorption species with varied dynamics were identified and assigned to the symmetric (s-) and unsymmetric (u-) Cr3(dpa)4Cl2. The major species is s-Cr3(dpa)4Cl2 that undergoes rapid conversion at less than 100 fs from the ligand-centred π–π* state, which is the initially accessed state, to the metal-centred d–d state and then vibrational cooling accompanying the structural relaxation at a time constant ∼2.2 ps. Most of the s-form is recovered to the ground state at ∼200 ps. For u-Cr3(dpa)4Cl2, a similar rapid conversion to d–d states is observed, and the geometric/vibrational relaxation is ∼0.8 ps. The second recovery of the ground state with approximately equal amplitude is observed at a time constant of ∼5 ns. This might be because many d–d states exist and about half of them inefficiently couple with the ground state surface.

The paper presents a study and comparative analysis of microfluids and nanofluids based on aqueous glycerol solutions, by study of the thermal conductivity, rheology, interfacial tension and solution stability. Cu, Ni and Al nanoparticles were used for preparation of the nanofluids. A newly synthesized monocrystalline pentanickel (II) metal string complex [Ni 5 (μ 5 -pppmda) 4 Cl 2 ] was used to form the microparticles which were compared with dispersed nickel microparticles.

A new pyrimidine-modulated ligand, N2-(pyridin-2-yl)-N6-(pyrimidin-2-yl)pyridine-2,6-diamine (H2pppmda) (1), its mononuclear copper(II) complex [Cu(H2pppmda)(CH3OH)](ClO4)2 (2) and pentanickel metal string complex [Ni5(μ5-pppmda)4Cl2] (3) have been synthesized and structurally characterized. X-ray analysis showed that the free ligand exhibits the syn–anti–syn–syn conformation and intermolecular hydrogen bonds link the ligand molecules to a 1-D network along the c axis. H2pppmda coordinates to the metal atom with all-anti mode in the copper mononuclear complex 2 and the coordination geometry of the Cu(II) ion is an elongated octahedron. The [Ni5(μ5-pppmda)4Cl2] complex involves a Ni5 linear chain unit where all the Ni–Ni–Ni angles are nearly 179° and which is terminated by the two axial ligands. The pentanuclear linear metal chain is helically wrapped by four syn–syn–syn–syn type pppmda2− ligands. There are two types of Ni–Ni distance in this complex. Terminal Ni–Ni distances bonded with the axial ligand are longer (2.3669(8) A); the inner Ni–Ni distances are short at 2.2987(6) A. The terminal Ni(II) ions bonded with the axial ligands are square-pyramidal (NiN4Cl) with long Ni–Nav bonds (2.096 A), consistent with a high-spin Ni(II) configuration. The inner three Ni(II) ions have short Ni–Nav bond distances (1.902(4)–1.888(4) A), consistent with a square planar (NiN4), diamagnetic arrangement of a low-spin Ni(II) configuration. This compound exhibits magnetic behavior similar to [Ni5(μ5-tpda)4Cl2], indicating an antiferromagnetic interaction of the two terminal high-spin Ni(II) ions. Electrochemical studies showed that the pentanickel(II) complex can undergo one reversible oxidation at +0.76 V. The introduction of an electron-withdrawing pyrimidine ring to the spacer ligand retarded the oxidation of the pentanickel metal string and stabilized the complex.

Based on the HMPA ligand, a new air- and moisture-stable pentagonal-bipyramidal DyIII single-ion magnet [Dy(HMPA)2(H2O)5]2·Br6·2HMPA·2H2O (1) was prepared and characterized. Single-crystal X-ray tests showed the two crystallographically independent DyIII ions located in a pentagonal-bipyramidal coordination sphere with strong axial HMPA ligands and weak equatorial water molecules relating to strong unaxial anisotropy. Direct-current and alternating-current magnetic susceptibilities were measured and showed that 1 exhibited slow relaxation of magnetization up to 36 K (1000 Hz) with an energy barrier of 556 K and blocking temperature of 7 K (defined by the peak temperature of zero-field cooling data). The application of a dc field and magnetic dilution were also carried out to explore the existing quantum tunelling of the magnetization process.

A series of Ti/Li/Al ternary layered double hydroxides (TiLiAl-LDHs) with different Ti:Li:Al molar ratios were prepared by a coprecipitation method for photocatalytic CO2 reduction. It was demonstrated that the contents of anions between the layers of Ti/Li/Al-LDHs greatly determined the photocatalytic activity for CO2 reduction. With Ti:Li:Al molar ratios optimized to be 1:3:2, the largest contents of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\bf{CO}}}_{{\bf{3}}}^{{\bf{2}}}$$\end{document}CO32− anion and hydroxyl group were obtained for the Ti1Li3Al2-LDHs sample, which exhibited the highest photocatalytic activity for CO2 reduction, with CH4 production rate achieving 1.33 mmol h−1 g−1. Moreover, the theoretical calculations show that Ti1Li3Al2-LDHs is a p-type semiconductor with the narrowest band gap among all the obtained TiLiAl-LDHs. After calcined at high temperatures such as 700 °C, and the obtained TiLiAl-700 sample showed much increased photocatalytic activity for CO2 reduction, with CH4 production rate reaching about 1.59 mmol h−1 g−1. This calcination induced photocatalytic enhancement should be related to the cystal structure transformation from hydrotalcite to mixed oxides containing high reactive oxygen species for more efficient CO2 reduction.

Based on the ligand 2,2′-dipyridylamine (Hdpa) and di（2-pyrazyl）amine（Hdpza）, neutral molecular complexes [Co(Hdpa)2(NCS)2] (1) and [Co(Hdpza)2(NCS)2] (2) were synthesized. The DFT calculation of complex 1 was carried out to analyze the electron density distribution. Magnetic results indicate that a gradual decrease in χMT over the entire temperature range indicates strong zero-field splitting for the high-spin Co(II) ion in 1. The complex was used for the cycloaddition reaction of CO2 and propylene oxide, and compared with the reported complex 2 [Co(Hdpza)(NCS)2], the catalytic activity was 1 > 2. The Complex 1 exhibited excellent catalytic performance for converting CO2 into cyclic carbonates under mild conditions. For propylene oxide (PO) and CO2 synthesis of propylene carbonate (PC), the catalytic system showed a remarkable TOF as high as 5040 h−1.

Through a pyrimidine and naphthyridine-containing triamine ligand, N2-(pyrimidin-2-yl)-N7-(2-(pyrimidin-2-ylamino)-1,8-naphthyridin-7-yl)-1,8-naphthyridine-2,7-diamine (H3N9-2pm), defective metal string complex [Ni8.33(N9-2pm)4(NCS)2](PF6)2 (1) was successfully synthesized and structurally characterized. The complex consists of a linear metal chain and four deprotonated supporting ligands which are helically wrapped around the metal score. X-Ray crystallographic studies revealed that the complex (1) crystallizes in space group P21/c of the monoclinic system. The small J value (J = −2.90 cm−1) suggests quite a weak magnetic interaction throughout the molecule of complex (1). The weak magnetic interaction in the defective complex indicates that the spin exchange in metal string occurs through the metal core rather than the bridging ligands. The electrochemical study on complex 1 shows abundant redox properties and facility to the reduction in its cyclic voltammogram by displaying three reversible redox couples at E1/2 = - 0.35, - 0.69 and – 0.88 V.

We aimed to develop new effective catalysts for the synthesis of propylene carbonate from propylene oxide and carbon dioxide. A kind of Mx+LClx coordination complex was fabricated based on the chelating tridentate ligand 2,6-bis[1-(phenylimino)ethyl] pyridine (L). The obtained products were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. It was found that the catalytic activity of the complexes with different metal ions, the same ligand differed and co-catalyst, where the order of greatest to least catalytic activity was 2 &gt, 3 &gt, 1. The catalytic system composed of complex 2 and DMAP proved to have the better catalytic performance. The yields for complex 2 systems was 86.7% under the reaction conditions of 100 &deg, C, 2.5 MPa, and 4 h. The TOF was 1026 h&minus, 1 under the reaction conditions of 200 &deg, C, 2.5 MPa, and 1 h. We also explored the influence of time, pressure, temperature, and reaction substrate concentration on the catalytic reactions. A hypothetical catalytic reaction mechanism is proposed based on density functional theory (DFT) calculations and the catalytic reaction results.

Based on the ligand H2dpPzda (1), a novel cobalt complex [Co(H2dpPzda)(NCS)2]&middot, CH3OH(2) has been synthesized and characterized. The Complex 2 exhibited excellent catalytic performance for converting CO2 into cyclic carbonates under mild conditions. For propylene oxide (PO) and CO2 synthesis of propylene carbonate (PC), the catalytic system showed a remarkable TOF as high as 29,200 h&minus, 1. The catalytic system also showed broad substrate scope of epoxide. Additionally, the catalyst could be recycled to maintain the integrity of the structure and remained equal to the level of its catalytic activity even after seven catalytic rounds. Additionally, a possible catalytic mechanism was proposed due to the high catalytic activity which might be owing to the synergism of Lewis acidic metal centers and N group.

To compare three different pathways for transurethral seminal vesiculoscopy (SVS) and investigate the reliability and efficiency of transrectal ultrasonography (TRUS)-guided SVS (TRUS-SVS).We retrospectively analyzed 90 cases of seminal vesiculoscopy conducted directly through the ejaculatory duct or prostatic utricle or under the guide of TRUS. We compared the success rate and complications among the three approaches.Operations were successfully performed in 87 (96.67%) of the 90 cases, 30 through the ejaculatory duct, 37 via the prostatic utricle, and 20 under the guide of TRUS, the operation time ranging from 25 to 75 minutes. Sperm was detected from the seminal vesicle fluid in (92.06%) of the azoospermia patients (58/63) during the surgery and in 77.78% of them (49/63) in semen analysis at 1 week postoperatively. Fifteen hematospermia and 12 spermatocystitis patients were cured. Postoperative follow-up found 20 cases of water-like semen and 3 cases of orchiepididymitis, but no such complications as retrograde ejaculation, incontinence, or rectourethral fistula.Transejaculatory duct and transprostatic utricle pathways are two common approaches to SVS, while TRUS-SVS may achieve a higher success rate and avoid injury of both the prostate and the rectum.目的: 总结实施精囊镜手术采用的3种不同进镜途径，探讨经直肠实时超声引导下精囊镜手术的可靠性和有效性。方法: 回顾性分析自2013年8月至2015年12月实施的精囊镜手术共90例，进镜途径为直接经射精管口、直接经前列腺小囊及经直肠实时超声引导下经前列腺小囊3种方式，进镜后对精囊疾病进行治疗，分别随访其治疗效果，比较3种进镜方式的成功率及并发症。结果： 90例患者手术时间为25~75 min，平均时间42.3 min,手术的总成功率为96.67%（87/90）。直接经射精管口（包括异位开口）途径进入精囊30例，６０例在正常解剖位置未找到射精管开口，采用经前列腺小囊途径进入精囊３７例，上述途径均失败后，采用经直肠实时超声引导下进入精囊20例，3例患者精囊镜手术失败。92.06%（58/63）无精子症患者术中精囊液查见精子，77.78%（49/63）术后1周精液常规见精子。15例血精及12例精囊炎患者术后随访均治愈。术后随访20例患者出现水样精液，睾丸附睾炎3例，无逆行射精、尿失禁及直肠损伤等并发症。结论： 经射精管口途径和经前列腺小囊途径为实施精囊镜手术的常规手术方法；而经直肠实时超声引导下经前列腺小囊途径能显著提高精囊镜检查成功率，避免术中对前列腺和直肠的损伤。.

Two defective nickel-extended metal-atom chain (EMAC) complexes were synthesized from a pyrazine- and naphthyridine-containing ligand and structurally characterized. The chains consist of dinickel and trinickel units with one absent metal center, in spite of which the complexes are very stable. The magnetic interaction between the two terminal, high-spin nickel atoms is very weak with a spin exchange of J = –0.62(3) cm–1. An electrochemical study on one of the defective nickel EMAC complexes showed high resistance to both oxidation and reduction, with one reduction at E1/2 = –0.76 V and no observable oxidation events in the range from –0.9 V to +1.20 V.

A series of rare earth metal complexes RE(TPP)(acac) (RE=NdIII, YbIII, EuIII, ErIII, PrIII and LuIII, TPP=5,10,15,20-tetraphenylporphyrin) were synthesized and characterized via UV-Vis, IR and elemental analyses. Their catalytic activities on the synthesis of cyclic carbonates from carbon dioxide and propylene oxide under different reaction conditions (temperature, pressure and reaction time) were investigated. Catalytic reaction tests demonstrated that the complex Lu(TPP)(acac) could significantly enhance the catalytic reactivity under mild conditions without any co-solvent.

Herein, the excited-state dynamics of an extended metal atom chain complex, Cr

The title compound,catena-poly[[[diaqua(methanol-κO)copper(II)]-μ-N-(4-methylpyrimidin-2-yl-κN1)pyrazin-2-amine-κ2N1:N4] [[aqua(aqua/methanol-κO)(perchlorato-κO)copper(II)]-μ-N-(4-methylpyrimidin-2-yl-κN1)pyrazin-2-amine-κ2N1:N4] tris(perchlorate) methanol monosolvate 1.419-hydrate], {[Cu(C9H9N5)(CH3OH)(H2O)2][Cu(C9H9N5)(ClO4)(CH3OH)0.581(H2O)1.419](ClO4)3·CH3OH·1.419H2O}n, is a one-dimensional straight-chain polymer ofN-(4-methylpyrimidin-2-yl)pyrazin-2-amine (L) with Cu(ClO4)2. The complex consists of two crystallographically independent one-dimensional chains in which the CuIIatoms exhibit two different octahedral coordination geometries. TheLligand coordinates to two CuIIcentres in a tridentate manner, with the pyrazine ring acting as a bridge linking the CuIIcoordination units and building an infinite one-dimensional chain. Extensive hydrogen bonding among perchlorate anions, water molecules andLligands results in three-dimensional networks.

Two pentacobalt(II) EMACs were synthesized. A pyrazine-modulated tripyridyldiamine resulted in an EMAC with fully delocalized Co-Co bonds along molecules. From a pyrazine- and naphthyridine-containing ligand, a defective cobalt linear EMAC with an 8-coordinated cobalt(II) in the center was obtained for the first time. An electrochemistry study on the defective pentacobalt chain compound showed redox peaks at E1/2 = -1.00, +0.76, and +0.98 V (versus EAg/AgCl), indicating that it is quite stable and very resistant to both oxidation and reduction. Research on magnetism revealed that the fully delocalized Co EMAC is a spin mixture, and the defective cobalt EMAC showed a high-spin mononuclear cobalt(II) behaviour with a magnetic moment of 2.63 μB per molecule at room temperature. Measurement on molecular electric conductance by STM bj showed a single-molecular resistance of 15.4 (± 3.1) MΩ for defective and 12.3 (± 2.6) MΩ for delocalized pentacobalt complexes.

An efficient rare earth metal complex-catalyzed cycloaddition reaction of CO2 with propylene oxide using Hdpza (di(2-pyrazyl)amine) as a N-donor ligand has been accomplished in good to excellent yields with high selectivity. The effects of different rare earth metal salts, ligands and reaction conditions were examined. Catalytic reaction tests demonstrated that the incorporation of ErCl3 and Hdpza can significantly enhance the catalytic reactivity of the TBAB (nBu4NBr, tetra-n-butyl ammonium bromide) towards cycloaddition reaction of CO2 and propylene oxide that produce cyclic carbonates under mild conditions without any co-solvent.

A 2-D grid copper(II) complex [Cu(μ3-H2dpzpda)(N3)]n(ClO4)n (2) has been synthesized and structurally characterized. The copper atom in the complex is six-coordinated in an octahedral geometry. The azide anions coordinated with copper in a 1-end form, and the perchlorate anions are not coordinated to copper centers. The structure shows an orthogonal overlap of orbitals through the bridging pyrazine. Extensive hydrogen bonds were observed in 2D networks. Magnetic studies indicate the presence of very weak antiferromagneic coupling between copper(II) ions.

The safety of the electricity network management system has become the important issue of concern by people today. SNMPv3 increased the security management mechanism on the basis of v1 and v2c, can resist the massage tampering, data intercepted, and other network security attacks effectively, ensured the reliability of network management better. This paper studies the modular frame structure of SNMPv3, introduces a new message structure and messages interaction process, shows the process of message handling based on USM(user-based security model). Finally, the USM is implemented in the actual electricity network management.

An efficient one-pot synthesis of hereto unknown indenoquinoline-spirooxindole derivatives by a three-component reaction of isatins, indan-1,3-dione, and 3-aminocyclohex-2-enone under the catalysis of acetic acid was developed. The procedure had the advantages of simplicity and efficiency.

New pentachromoium metal string complexes [Cr5(μ5-L)4X2] (X = Cl−, L = dppzda2− (1), dpzpda2− (2); X = NCS−, L = dppzda2− (3), dpzpda2− (4)) were designed and synthesized through pyrazine-modulation of tripyridyldiamine ligand. X-Ray crystallographic studies revealed a linear metal chain structure consisting of two quadruple Cr–Cr bonds and a separated high spin Cr(II) at an end in crystallized form. A quintet ground state was observed for all pentachromium(II) molecules by magnetic study with g values of 2.04–2.18. While the electronic structure remained unchanged after the modification of ligands, electrochemistry showed a significant change in the molecular orbital energy levels of metal string molecules. Observation of the first oxidation peak of 1 at +0.57 V and of 2 at +0.73 V revealed that these complexes are quite resistant to oxidation. Single molecular conductance measurements showed that the complex exhibited good electronic conductance.

A novel complex [Ru(phen)3][Cu(opba)]‧6H2O has been prepared and characterized structurally. The crystal structure showed that the complex consisted of dication [Ru(phen)3]2+and complex dianion [Cu(opba)]2–. The IR, Uv-vis, EPR spectra were studied, and EPR spectra showed hyperfine structure from copper isotopes63Cu and65Cu, and superhyperfine(shf) from14N coupling, giving parameters g// = 2.207，g = 2.026，A//Cu= 196 G，ACu= 43 G，A//N= 13 G，AN= 17 G. The bond parameters were evaluated based on the EPR spectra, indicating substantial π-bonding character in the Cu–N and Cu–O bonds in the complex [Cu(opba)]2–. The spin density on nitrogen and oxygen atoms is 0.081 and 0.195, respectively.

Therapeutic numbers of antigen-specific cytotoxic T lymphocytes (CTLs) are key effectors in successful adoptive immunotherapy. However, efficient and reproducible methods to meet the qualification remain poor. To address this issue, we designed the artificial antigen-presenting cell (aAPC) system based on poly(lactic-co-glycolic acid) (PLGA). A modified emulsion method was used for the preparation of PLGA particles encapsulating interleukin-2 (IL-2). Biotinylated molecular ligands for recognition and co-stimulation of T cells were attached to the particle surface through the binding of avidin-biotin. These formed the aAPC system. The function of aAPCs in the proliferation of specific CTLs against human Flu antigen was detected by enzyme-linked immunospot assay (ELISPOT) and MTT staining methods. Finally, we successfully prepared this suitable aAPC system. The results show that IL-2 is released from aAPCs in a sustained manner over 30 days. This dramatically improves the stimulatory capacity of this system as compared to the effect of exogenous addition of cytokine. In addition, our aAPCs promote the proliferation of Flu antigen-specific CTLs more effectively than the autologous cellular APCs. Here, this aAPC platform is proved to be suitable for expansion of human antigen-specific T cells.

A ruthenium(III) complex containing ethylenediaminetetraacetate (edta), [{Ru(Hedta)}2(Pyz)] · 8H2O (1) (Pyz = pyrazine), has been synthesized by the reaction between K[Ru(Hedta)Cl] · 1.5H2O and pyrazine. The structure of the complex was determined by single X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 with a = 7.293(9) A, b = 10.575(14) A, c = 12.742(16) A, α = 104.044(19)°, β = 91.893(19)°, γ = 93.35(2)°, Z = 1. The product was also characterized by IR, UV-Vis, EPR spectrum and magnetic techniques.