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Aim: This study explored the effect of public health nurses’ current community care nursing competency on the psychological and organizational empowerment of public health services in Taiwan. Design: A cross-sectional nationwide survey design was used. Methods: A self-developed structured questionnaire was administered to public health nurses. They were recruited using a purposive sampling technique, and they participated in community healthcare workshops. Results: The mean score of Community Care Nursing Competence (CCNC) was 3.92 ± 0.83. The mean score in Community Empowerment (CE) was 3.66 ± 0.90. The study revealed that age and communication competence were crucial factors in public health nurses working in the community. With age and through the accumulation of practical experience, public health nurses’ communication competence may also improve, which can further enhance their psychological and organizational empowerment in the nursing workplace.

The influence of thermal shock behavior between 960 °C and room temperature on microstructure and tensile properties of IN718 alloy after three heat treatments was investigated in this paper. The experiments show that protective and dense oxide films with the composition of Cr2O3, Ti0.95Nb0.95O4 and (Cr, Fe)2O3 are formed on the surface of alloys. The average oxide films increased with the thermal shock cycle. The thermal shock behavior changed the distribution and quantities of δ phases, which have significantly reduced the strength and increased the elongation of IN718 alloy. The decrease of strength was mainly determined by the dissolution of strengthening phase and grain coarsening. High standard treatment alloy shows the best thermal shock resistance since the strength decreased smallest after thermal shock.

Radar Maneuvering Targets Tracking (RMTT) in clutter is a quite challenging issue due to the errors in the models and the varying dynamics of the processes. Modern radar tracking system calls for the adaptive signal and data processing algorithm urgently to adapt the uncertainty of the environment. The mechanism of human cognition can help persons cope with the similar difficulties in visual tracking. Inspired by human cognition mechanism, a comprehensive method for RMTT is proposed. In the method, the model transition probability in Interacting Multiple Model (IMM) and the validation gate can be adjusted dynamically with target maneuver; the waveform in radar transmitter can vary with the perception of the environment. Experimental results in cluttered scenes show that the proposed algorithm is more accurate for perceiving the environment and targets, and the waveform selection algorithm is better than that with fixed waveform. Keywords: Human visual attention, Memory, Radar Maneuvering Targets Tracking, Validation gate, Waveform selection

An oxa-[4+2] cyclization of quinone methides with alkynyl benzyl alcohols has been realized in the presence of a metal catalyst, and the reaction afforded spiroacetal products in overall high yields (up to 99%) and good diastereoselectivities (up to >95:5 dr). By carrying out the reaction under gold catalysis and utilizing alkynyl benzyl alcohols as electron-rich reaction partners, this approach provides a useful strategy for settling the challenges in oxa-[4+2] cyclization of para-quinone methide derivatives. This reaction serves as a good example for metal-catalyzed oxa-[4+2] cyclizations of quinone methides. In addition, it also offers a useful method for the construction of spiroacetal skeletons.

Cement was used in oil industry to fix well. After hydration of cement, a porous material with overbased pore solution will be formed. Passivation analysis will be conducted on the passivation of the outer wall of downhole P110 casing steel under overbased conditions. Due to the difficulty of obtaining cement pore solution, two kinds of simulated concrete pore solutions (SP solution, CF solution) were used to carry out experiments. The different properties of passive film in two different solutions were obtained, which provided reliable data to support for the research of passive film properties of casing steel. Therefore, the electrochemical properties were characterized by electrochemical impedance spectroscopy (EIS), polarization curves method and Mott-Schottky curves method during the formation of the passive film. Moreover, X-ray photoelectron spectroscopy (XPS) was measured to qualitatively analyze the composition of the passive film on the casing surface, and scanning electron microscope (SEM) was used to observe surface morphology of the P110 casing steel. The result showed that the passive film was enhanced with time increasing and the time for complete passivation of P110 steel in two simulated concrete pore solutions was different, requiring longer passivation in CF solution. The passive film in the CF solution had a larger film resistance and the film layer was more stable. The semiconductor characteristics of the passive film were n-type and the donor density of the passive film in CF solution was lower than that of the SP solution. The passive film formed in two simulated concrete pore solutions was all Fe oxides, but not completely the same. Also the steady-state passive film formed in the two solutions had a different microscopic morphology.

A catalytic asymmetric α-arylation of aldehydes using 2-indolylmethanols as arylation reagents has been established. This reaction was enabled by a cooperative catalytic system consisting of a gold complex, a Bronsted acid, and a chiral amine, which have a synergistic effect in the reaction process. By using this strategy, a series of α-arylation products of aldehydes were generated in overall acceptable yields and good enantioselectivities (up to 69%, 91:9 er). The control experiments demonstrated that the addition of PPh3AuCl as a gold complex was helpful to improve the yield, and trifluoroacetic acid as a Bronsted acid played a crucial role in the reaction by promoting the generation of carbocation and chiral enamine intermediates, which are two key intermediates of the asymmetric α-arylation reaction. In addition, the enantioselectivity of the reaction was mainly controlled by the chiral amine catalyst via forming a chiral enamine intermediate. This reaction has not only provided a useful protocol for...

A new tunable Cu(I)-catalyzed site-selective dehydrogenative amination of β,γ-unsaturated hydrazones has been established using readily accessible dioxygen as a green oxidant. The presence of Cu2O/O2 regiospecifically accessed densely functionalized pyrazol-4-ones with one quaternary carbon-amino functionality, in which O2 acted as both a reaction component and an oxidant, whereas the employment of CuI/O2 as a catalytic oxidation system resulted in 1,6-dihydropyradazines with good yields.

A sustainable and efficient visible-light-induced Ir(III)-catalyzed annulation of 1,7-diynes with ICF2CO2Et is reported under mild neutral-redox conditions, furnishing a wide range of difluoromethyl-containing (1E,2E)-tetrahydronaphthalen-1-ols bearing two exocyclic double carbon–carbon bonds as major stereoisomers in good yields with high stereoselectivity. Notably, the high stereoselectivity could be observed in most cases. The photocyclization protocol has attractive characteristics of complete atom economy, good compatibility with different types of substituents, and the efficient control of stereochemistry.

The catalytic asymmetric [3 + 2] cycloaddition of 2-indolylmethanols to p-hydroxystyrenes was established in the presence of a chiral phosphoramide, and this reaction provided chiral cyclopenta[b]indole scaffolds in generally high yields and with good enantioselectivities (up to 98% yield, 99:1 er). The control experiments demonstrated that the dual hydrogen-bonding activation mode of the chiral catalyst toward the two substrates played an important role in the reaction. In addition, the large-scale reaction indicated that this catalytic asymmetric [3 + 2] cycloaddition could be scaled up for the synthesis of chiral cyclopenta[b]indole derivatives.

A new C-center radical-triggered bicyclization cascade of N-tethered 1,7-enynes for forming 28 examples of biologically interesting spirocyclohexadienone-containing cyclopenta[c]quinolin-4-ones with two all-carbon quaternary stereocenters has been established under mild conditions. The in situ generated diazonium salts from 4-methoxyanilines and t-BuONO are served as 4-methoxyphenyl precursors without additional oxidant, enabling 6-exo-dig cyclization/5-exo-trig ipso-cyclization to construct three new C-C bonds through metal-free dearomatization. The reaction also features broad substrate scope, annulation efficiency, and high functional group tolerance.

A new Ag-catalyzed oxidative bicyclization of N-tethered 1,7-enynes with alkylcarboxylic acids for forming 41 examples of polycyclic 3,4-dihydroquinolin-2(1H)-ones has been established using readily accessible K2S2O8 as an oxidant. The reaction pathway involves a silver-catalyzed decarboxylation/in situ-generated C-center radical-triggered α,β-conjugated addition/6-exo-dig cyclization/H-abstraction/5-endo-trig cyclization/SET sequence, allowing direct site-selective decarboxylative C(sp3)–H functionalization toward the formation of multiple C–C bonds and rapid construction of complex spiroheterocycles.

A novel three-component bicyclization strategy for the metal-free synthesis of densely functionalized indeno[1,2-c]furans with generally good yields has been established from readily accessible o-phthalaldehydes (OPA), isocyanides, and α-diazoketones. The reaction pathway involves aldol-type addition, 1,2-hydride shift, 5-exo-trig cyclization, and 1,4-addition as well as an oxo-5-exo-dig cyclization sequence, resulting in continuous multiple bond-forming events including C-C and C-O bonds to rapidly build up functional oxo-heterocycles.

A new metal-free three-component 1,5-enyne-bicyclization has been established for the stereoselective construction of sulfonylated anti-indeno[1,2-d]pyridazines using I2/TBHP catalytic oxidative system, in which arylsulfonyl hydrazides function as both the ring component and sulfonyl radical precursor. This reaction pathway involves a Michael addition, 5-exo-dig carbocyclization, H-abstraction and 6-endo-trig aza-cyclization sequence, resulting in continuous multiple bond-forming events including C–S, C–C, and C–N bonds to readily build up functional aza-heterocycles.

A multi-component bicyclization strategy has been established, allowing a flexible and practical approach to 29 examples of skeletally diverse fused quinazolines from low-cost and readily accessible aldehydes with cycloketones and cyanoamides. The reaction is easy to perform simply by mixing three common reactants and Cs2CO3 in ethylene glycol under microwave irradiation and can be finished within 25 min with water as a sole byproduct. A sequence cascade process consisting of Knoevenagel condensation/[4+2] cyclization/intramolecular aza-Michael addition/aza-nucleophilic reaction-ring opening is involved in this new scaffold generating reaction. During this sequence, four stereogenic centers with one quaternary carbon-amino functionality have been controlled very well; and the stereochemistry has been unequivocally determined by X-ray structural analysis.

In order to realize the application of large-area laser-clad coatings, the overlap of individual laser tracks is required. However, the feature of the overlap zone (C1) is different from non-overlap zone (C2) in multi-track laser-clad coating ascribed to the secondary thermal effect of the laser beam. Microstructural analysis showed that the coarse columnar structure and uniform cellular structure were found in C1 and C2, respectively. Meanwhile, the secondary thermal effect caused C1 a higher content of Fe diffused from the carbon steel substrate than C2. Electrochemical analysis displayed that C2 had a higher polarization resistance, a lower and more stable current density at under passive potential, and a lower donor density than C1. The corrosion morphology and elemental valence states analysis showed that C1 presented more serious inter-phase corrosion than C2 because of the higher elemental change between primary and eutectic phases. Meanwhile, C2 owned denser passive film than C1 considering higher contents of metallic oxidation states on the surface.

The thermodynamic assessments of the Au–Gd and Au–Yb binary systems have been carried out by the Calculation of Phase Diagram (CALPHAD) method based on the available experimental data. The Gibbs free energies of the solution phases including liquid, fcc, bcc, and hcp were described by the substitutional solution models with the Redlich–Kister equation. All the intermetallic compounds except the βAuYb phase were treated as stoichiometric phases, and the βAuYb phase was modeled using the sublattice model. The thermodynamic parameters of each phase in the Au–Gd and Au–Yb binary systems were obtained, and an agreement between the calculated results and experimental data was obtained in each binary system.

Sc-based alloys have been used as aero-structures materials, and Sc addition on wrought alloys has positive effects on weldability and welding properties. Phase diagrams play an effective role during the development of new type of alloy with good properties. Therefore, to establish the thermodynamic database of Sc-X binary systems is important and necessary.In the present work, the thermodynamic assessments of Sc-X (Ag, B, Cr, Er, Gd, Mo, Th, W, Y, Zr) binary systems was carried out by using CALPHAD (Calculation of Phase Diagrams) method based on the experimental data including thermodynamic properties and phase equilibria. The Gibbs free energies of the solution phases were described by the sub-regular solution model with the Redlich-Kister equation, and those of the intermetallic compounds were described by the sub-lattice model. A set of self-consistent thermodynamic parameters were derived for describing the Gibbs free energies of each solution phase and intermetallic compound. The calculated phase diagrams and thermodynamic properties are in good agreement with experimental data. The thermodynamic database of the Sc-X (Al, Ag, B, Ca, Co, Cr, Cu, Er, Fe, Ga, Gd, Ge, La, Li, Mg, Mn, Mo, Ni, Pb, Pd, Ru, Sn, Th, W, Y, Zn, Zr) binary systems have been developed, which can provide much important thermodynamic information for multicomponent Al-Sc based alloys.

The thermodynamic database has been developed for Au-RE binary systems. Based on the experimental data including thermodynamic properties and phase equilibrium, the thermodynamic assessments of phase diagrams in the Au-RE (RE: Nd, Dy, Yb, Gd, Tb, Sm, Lu) binary systems were carried out by using the CALPHAD (Calculation of Phase Diagrams) method. The Gibbs free energies of the solution phases were described by substitutional solution model, and all of the intermetallic compounds were described by sublattice models. The calculated phase diagrams are congruent with the available experimental data. Combined with the assessed Au-RE (RE: La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) binary systems, the thermodynamic database of Au-RE binary systems has been developed, and some significant information of thermodynamic properties and phase equilibrium could be calculated, which is important for the further development of Sn-Au-RE high-temperature lead-free solders.

With available melting point and hardness, the Bi-based filler alloy is considered as one choice of high-temperature Pb-free solder. Phase diagram can play an important role in the design of new type of Pb-free solder.In the present work, the thermodynamic assessments of the Au-Nd and the Au-Lu binary systems have been carried out by the Calculation of Phase Diagram (CALPHAD) method based on the available experimental data. The Gibbs free energies of the solution phases were described by subregular solution models with the Redlich-Kister equation, and those of the intermetallic compounds were described by sublattice models. A set of self-consistent and reasonable thermodynamic parameters is obtained for the binary systems, which describes the Gibbs energies of the solution phases and the intermetallic compounds phases. Additionally, combined the reported Bi-Au, Bi-Lu and Bi-Nd binary systems, the thermodynamic database of the Bi-Au-Lu and the Bi-Au-Nd ternary systems have been developed, which will provide important thermodynamic information for the phase equilibria of the multicomponent Bi-based alloy systems.

A new base-promoted bicyclization strategy for the synthesis of functionalized indeno[1,2-b]pyran-2-ones has been established from readily accessible o-phthalaldehydes (OPA) and the preformed 1-arylethylidenemalononitriles. The reaction pathway involves an aldol addition, 5-exo-trig carbocyclization and 6-exo-dig oxo-cyclization sequence, resulting in continuous multiple C–C and C–O bond formation.

Dual cobalt(II)/silver catalysis enables multicomponent bicyclization cascades of 2-ethynylanilines, tert-butyl isocyanide, and arylamines, resulting in subsequent multiple bond-forming events to rapidly build up aryliminated pyrrolo[2,3-b]indoles. The reaction pathway involves bimetal-catalyzed isocyanide insertion/1,3-dipolar cycloaddition/imination substitution sequence.

To explore the relationship between expression of CD96 and CD123 and prognosis of patients with myelodysplastic syndrome(MDS).Eight-nine MDS patients(MDS group) and 20 persons without hematologic disease as controls(Control group) were enrolled. The patients were grouped by the risk. All participants received bone marrow biopsy. Mononuclear cells were extracted, CD34The proportion of CD34The differentiation of CD34

Three-component [3 + 3] heterocyclizations have been established under microwave irradiation, providing a flexible synthetic approach toward bicyclic fused pyridines. 3,5-Dibenzylidenedihydro-2H-pyran-4(3H)-ones were subject with malononitrile and aromatic amines in cosolvent of HOAc and N,N-dimethylformamide, affording 10 examples of pyrano[4,3-b]pyridine derivatives in good to excellent yields. Similarly, seven examples of thiopyrano[4,3-b]pyridine derivatives were obtained using sulfur-tethered heterocyclones as a reaction partner.

The pitting behavior of 304 stainless steel in the simulated condensate with different salt content (4 mg/L, 8 mg/L, 16 mg/L, 32 mg/L, 64 mg/L) and sulfur content (1.2 g/L, 2.5 g/L, 5 g/L) was studied using potentiodynamic polarization curve and static immersion methods. The simulated condensate was simulating the condensed water in the unit of refining heavy oil with high salt and high sulfur. The results showed that with the increase in chloride ions concentration, the pitting potential of 304 stainless steel decreased and the pitting sensitivity increased. The pitting sensitivity of 304 stainless steel also increased with the increase in sulfide ions concentration. In several experimental mediums, when the concentration of chloride ions and sulfide ions were 64 mg/L, 5 g/L respectively, the number and the size of corrosion pits both were the largest, the pitting behavior was the most serious.

The addition of the rare earth elements into the Ag-based filler alloy, which is typical and important, can control and eliminate the negative effect of impurity elements, and furthermore, it improves the spreading property of the Ag-based filler alloy. Phase diagram provides an important direction for materials design of the Ag-based filler alloy. Thus it is necessary to investigate the phase diagrams and construct the thermodynamic database. On the basis of this background, thermodynamic assessments of the Au-Gd, Tb binary systems were carried out by using the CALPHAD (Calculation of Phase Diagrams) method based on the experimental data including thermodynamic properties and phase equilibrium. The Gibbs free energies of the solution phases were described by sub-regular solution models with the Redlich-Kister equation, while all of the intermetallic compounds were described by sub-lattice models. A consistent set of thermodynamic parameters was derived from describing the Gibbs free energies of each solution phase and intermetallic compound. The calculated phase diagram achieved consistency with the available experiments. Then combined with the assessed relevant binary systems, the Ag-Au-Gd, Tb ternary systems have been predicted. The thermodynamic database of these ternary systems has been developed to present the significant information for the design of Ag-based filler alloys.

Base-promoted transannulation of heterocyclic enamines and 2,3-epoxypropan-1-ones has been successfully achieved, providing a new access to structurally diverse fused pyridines and pyrroles with excellent regio- and stereoselectivity. Treatment with N-aryl 4-aminofuran-2(5H)-ones and 2,3-epoxypropan-1-ones under microwave heating resulted in functional furo[3,2-b]pyridines in good yields. The N-aryl 4-aminopyrrol-2(5H)-ones bearing an electron-withdrawing group engaged in the reaction afforded pyrrolo[3,2-b]pyridines, whereas their counterparts with an electron-neutral or an electron-donating group underwent a different reaction pathway to form pyrrolo[3,2-b]pyrroles through C-C bond cleavage.

A catalytic bicyclization reaction of 1,5-enynes anchored by α,β-conjugates with arylsulfonyl radicals generated in situ from sulfonyl hydrazides has been established using TBAI (20 mol%) and Cu(OAc)2 (5 mol%) as co-catalysts under convenient conditions. In addition, the use of benzoyl peroxide (BPO) as the oxidant and pivalic acid (PivOH) as an additive was proven to be necessary for this reaction. The reactions occurred through 5-exo-dig/6-endo-trig bicyclizations and homolytic aromatic substitution (HAS) cascade mechanisms to give benzo[b]fluorens regioselectively. A similar catalytic process was developed for the synthesis of γ-ketosulfones. These reactions feature readily accessible starting materials and simple one-pot operation.

By using the calculation of phase diagrams (CALPHAD) method, the thermodynamic assessments of the Sc-M (M: Cr, Gd, Mo, W and Zr) binary systems were carried out based on the available experimental data including thermodynamic properties and phase equilibria. Gibbs free energies of the liquid, hcp and bcc phases in the Sc-M (M: Cr, Gd, Mo, W and Zr) binary systems were modeled by the substitutional solution model. An agreement between the present calculated results and experimental data was obtained.

New multicomponent domino reactions of arylglyoxals with pyrazol-5-amines have been established, providing selective access to unprecedented pyrazolo-fused 1,7-naphthyridines, 1,3-diazocanes, and pyrroles (up to 52 examples). The unreported dipyrazolo-fused 1,7-naphthyridines were regioselectively synthesized through a special double [3 + 2 + 1] heteroannulation accompanied by direct C–C formation between two electrophilic sites of arylglyoxals. The unusual [3 + 3 + 1 + 1] cyclization resulted in 20 examples of novel dipyrazolo-fused 1,3-diazocanes, whereas pyrrolo[2,3-c]pyrazoles were obtained in good yields by varying arylglyoxals 1 and pyrazol-5-amines 2 in the ratio 1:2. Mechanisms of formation of these three new types of heterocycles are also proposed.

Concise and efficient base-promoted domino formal (3+3) cycloaddition has been established for the formation of tetracyclic indolo[2,3-b]quinoline derivatives under microwave heating. The present methodology shows attractive properties, such as the maximum efficiency of a process, short reaction periods, and operational simplicity, and it can avoid time-consuming and costly syntheses, tedious work-up and isolation of intermediate. This chemistry provides a facile and promising synthetic strategy to construction of tetracyclic indolo[2,3-b]quinoline skeleton.

A novel four-component strategy for the selective synthesis of fused azepino[5,4,3-cd]indoles and pyrazolo [3,4-b]pyridines has been established. The bond-forming efficiency, accessibility of starting materials and substrate scope provide invaluable access to tetra-, and bis-heterocyclic scaffolds.

A new base-promoted bicyclization strategy for the synthesis of functionalized indeno[1,2-b]pyran-2-ones has been established from readily accessible o-phthalaldehydes (OPA) and the preformed 1-arylethylidenemalononitriles. The reaction pathway involves an aldol addition, 5-exo-trig carbocyclization and 6-exo-dig oxo-cyclization sequence, resulting in continuous multiple C–C and C–O bond formation.

Three-component [3 + 3] heterocyclizations have been established under microwave irradiation, providing a flexible synthetic approach toward bicyclic fused pyridines. 3,5-Dibenzylidenedihydro-2H-pyran-4(3H)-ones were subject with malononitrile and aromatic amines in cosolvent of HOAc and N,N-dimethylformamide, affording 10 examples of pyrano[4,3-b]pyridine derivatives in good to excellent yields. Similarly, seven examples of thiopyrano[4,3-b]pyridine derivatives were obtained using sulfur-tethered heterocyclones as a reaction partner.

A novel synergistic rhodium/copper catalysis has been established, enabling de-diazotized cycloadditions of 1,5-enynes and α-diazocarbonyls toward the selective formation of densely functionalized benzo[b]fluorenes and 2-naphthalenylmethanones. α-Aryldiazoesters result in the formation of triple C–C bonds through bimetallic catalysis whereas a range of functionalized naphthalenes with a 1,5-dicarbonyl unit were accomplished using α-diazocarbonyls without any substituent at the α-position, indicating that substituents at the α-position of the α-diazocarbonyl unit could control the selectivity of the reaction.

Structures with long span and high flexibility are very sensitive to the wind forces, so it is necessary to study on the wind effects on such structures. In this paper, based on section model wind tunnel high-frequency force balance tests, two horizontal base bending moments and shear forces of the typical supporting columns as well trestle bridge deck of the closed coal trestle under different wind directions were measured. The shape coefficients and their variations with the wind directions of the typical supporting columns as well trestle bridge deck were calculated then analyzed by the mean values of base forces. The experimental values of the shape coefficients were compared with those in the Chinese Load Code, the results shown that both were in good agreement, which verified the reliability of the test, which also illustrated that wind-resistant design of the coal trestle in accordance with the Code was reasonable. Based on analysis of the variances of base forces between overall model with and without surrounding buildings, influences of surroundings buildings were studied. Interference factors were proposed which provided the basis for the base forces checking and wind-resistant design of the long-span closed coal trestle structures.

The thermodynamic assessments of the Au-Tb and Au-Lu binary systems were carried out by means of the CALPHAD method based on the experimental data including the thermodynamic properties and phase equilibria. The Gibbs free energies of the liquid, bcc, fcc and hcp phases were described by the substitutional solution model, while all of the intermetallic compounds (Au6Tb, Au51Tb14, Au3Tb, Au2Tb, Au10Tb7, Au4Tb3, αAuTb, βAuTb, AuTb2, Au4Lu, Au3Lu, Au2Lu, AuLu and AuLu2 phases) in these two binary systems were treated as the sublattice model. Consequently, a set of self-consistent thermodynamic parameters of each phase in the Au-Tb and Au-Lu binary systems has been obtained, and the calculated results are in good agreement with the available experimental data.

The selective formation of pyrazole-substituted fused pyrroles through HOAc-mediated multicomponent reactions of enaminones with arylglyoxal monohydrates and generated in situ pyrazole-3-carboxylates was developed. It constructed a variety of bis-heterocyclic pairs under mild conditions in a domino process. Reaction driving tandem cyclization/allylic esterification/allylic substitution was achieved through the formation of in situ generation of allyl esters and pyrazole-3-carboxylates from readily available starting materials. Up to two new five-membered heterocyclic rings and five new sigma bonds including a C(sp3)–C(sp2) bond were formed in a single reaction without isolated intermediates.