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Four different tetrazole–carboxylate ligands, monotetrazole–carboxylate Hatza (Hatza = 5-aminotetrazole-1-acetic acid), Hpytza (Hpytza = 5-(4-pyridyl)tetrazole-2-acetic acid), ditetrazole–carboxylate H2datza (H2datza = N,N-di(tetrazol-5-yl)amine-N2,N2′-diacetic acid) and tristetrazole–carboxylate, H3tzpha (H3tzpha = 1,3,5-tris(tetrazol-5-yl)benzene-N2,N2′,N2′′-trisacetic acid) have been chosen to be reacted with zinc salts, resulting in the formation of four novel compounds, [Zn(atza)2(H2O)4] (1), [Zn(pytza)2] (2), [Zn(datza)(H2O)2]·3H2O (3) and [Zn3(tzpha)2(H2O)12]·MeOH·EtOH·4H2O (4), whose structures are controlled by not only the number and different coordination modes of the tetrazole–carboxylate but also the complementary hydrogen bonds. These compounds have been characterized by elemental analysis, IR and single crystal X-ray diffraction. Compound 1 displays a simple zero dimensional mononuclear structure, 2 shows a classic 3D 8-connect (36, 416, 56) tsi network topology, 3 features a 1D ladder-like chain while 4 is a 1D beaded chain. Furthermore, the luminescence properties investigated at room temperature in the solid state show excellent ligand-centered luminescence.

Reactions of four different tetrazole-containing carboxylic acids and 4,4′bipyridine with ZnCl 2 ·6H 2 O, produced four new coordination compounds, [Zn(pytza) 2 (4,4′-bipy)(H 2 O) 2 ]·2H 2 O ( 1 ), (pytza = 5-(3-pyridyl)tetrazole-2-acetato), [Zn(tzpya) 2 (4,4′-bipy)(H 2 O) 2 ]·8H 2 O ( 2 ) (tzpya = 4-(5-tetrazolyl)pyridine-1-acetato), [Zn(4,4′-bipy)(H 2 O) 4 ]·2(pztza)·2H 2 O ( 3 ) (pztza = 5-(2-pyrazinyl)tetrazole-2-acetato). [Zn(atza) 2 (4,4′-bipy) 0.5 ·H 2 O] ( 4 ) (atza = 5-aminotetrazole-1-acetato). These compounds were structurally characterized by elemental analysis, IR spectroscopy, UV–Vis spectroscopy, thermogravimetric analysis and single crystal X-ray diffraction. The X-ray diffraction reveals that compounds 1 – 3 display 1D polymeric chains while 4 shows a 2D layer structure. Compounds 1 – 4 are self-assembled to form 3D networks by hydrogen bonding interactions. Furthermore, the luminescent properties were also investigated at room temperature in the solid state.

Magnetic resonance imaging (MRI) is a sensitive diagnostic method in improving the diagnostic capacity for hepatic cirrhosis and determining the accurate characterization of hepatic cirrhosis. But hepatic MRI has some shortcomings in detection and classification hepatic cirrhosis in clinical, especially using non-enhanced MRI for diagnosing early hepatic cirrhosis. And computer-aided diagnostic (CAD) system, including quantitative description of lesion and automatically classification, can provide radiologists or physicians an alternative second opinion to efficiently apply the abundant information of the hepatic MRI. However, it is expected to character comprehensively the lesion and guarantee high classification rate of CAD system. In this paper, a new CAD system for hepatic cirrhosis detection and classification from normal hepatic tissue non-enhanced MRI is presented. According to prior approach, six texture features with different properties based on gray level difference method are extracted from regions of interest (ROI). Then duplicative-feature support vector machine (DFSVM) is proposed for feature selection and classification: Firstly, the search process of DFSVM imitates diagnosis of doctors: doctor will take a more feature for consideration until the final diagnoses regardless of whether the feature is used in advance. So our algorithm is consistent with the process of clinical diagnosis. Secondly, the impact of the most valuable features will be well strengthened and then the high prediction performance can be got. Experimental results also illustrate the satisfying classification rate. Performance of extracted features and normalization are studied. And it is also compared with typical classifier ANN.

The cracking bending strength for steel-polypropylene hybrid fiber reinforced concrete (HFRC) had been studied based on experimental test. the inicial cracking strength achieve significant improvement compare to plain concrete, and the highest increase is 16.7%. There is a synergistic effect exist when steel fiber is 1.0% in volume or polypropylene fiber is 0.1% in volume, and the synergistic effect raise to vertex (1.043) when both of those two requirements are fulfilled.

Three different volume ratio steel fiber and polypropylene fiber were mixed into concrete matrix to study the hybrid effect of fibers. Cube HFRC specimens were tested under uniaxial and triaxial load. Hybrid effects on compressive strength of the results were analyzed and compared. It was founded that there were positive and negative effects in HFRC under compression. Positive hybrid effects of HFRC could be found when volume ratios of fiber (no less than 1.0% for steel fiber and 0.1% for polypropylene fiber) were added into HFRC.

In allusion to the status quo of deficient in evaluation theory and methods on the social risk of dam-break, this paper established 24 index systems for the evaluation of dam-break social risk composed by the dam-break hazard intensity, accident probability, hazard-affected body inherent vulnerability and disaster relief capacity. The quantitative calculation formula has also been put forward for evaluation indexes. In line with the Delphi method, a judgment matrix on the social risk caused by dam-break has been constructed, and has obtained the weight of each index by virtue of analytic hierarchy process. The results show the internal friction angle, the downstream main ditch longitudinal gradient, the current dam height and the monitoring & forecasting capacity are the key indicators that affect the social risks of dam-break. The results of this study help to further enhance and improve the technical level of risk evaluation for the tailings pond.

The method, using slope buckling safety factor to measure the degree of dam-break hazard, results in the unscientific conclusions of identical dam-break risk with respect to the desolate & uninhabited gobi desert and densely populated & highly economic-developed city. On the basis of vulnerability theory, a dam-break hazard vulnerability assessment index system, which comprehensively considering the inherent risks of dam-break and the intrinsic vulnerability of hazard-affected bodies, was established. The production of dam-break hazard-causing factor intensity, including the current dam height, reservoir capacity & downstream main ditch longitudinal, and accident probability by the Monte Carlo method is the inherent risk level of dam-break. The result by the multiplying physical exposure and the intrinsic vulnerability, including household fitness index & the emergency self-help index, as well as the disaster relief capacity is the hazard-affected body vulnerability. Results are contributable to further consummate the vulnerability risk assessment technology and the reliability of dam-break hazard.

The dynamic risk of underground cavities after gas outburst in coal uncovering construction of hydropower station was emphatically analyzed. The tunnel construction conditions in Xiangjiaba hydropower station were taken as an example. Based on the computational fluid dynamics theory and gas outburst theory, this paper used the ANSYS CFX CFD code to model the gas diffusion after gas outburst. The space-time characteristics of underground cavities dynamic risk were analyzed. The results show that the danger area ranges of gas explosion and asphyxia reach respectively the maximum value at about 140s and 50s. The influence range and duration of the former are significantly higher than the latter. The direction of hazardous area movement is mainly consistent with the air flow direction. ANSYS CFX simulation can visually display dynamic risk of underground cavities, and has a good prospect in gas hazard prevention in hydraulic and hydroelectric engineering.

Orthogonal tests are designed for hybrid fiber reinforced concrete. Bending toughness of hybrid fiber reinforced concrete, with the substrate intensity C30, the quantity of the volume for the steel fiber dosage 0~1.5% and polypropylene fiber dosage 0~0.3%, are studied. The results show that the hybrid fibers significantly improve the toughness of the concrete matrix. When the dosage reaches to a certain number, the affection of fiber toughness is decreased. Based on the test results the best dosage of hybrid fibers which is the steel fiber 1% mixed with 0.1% polypropylene fiber is recommended.

For the sensing applications based on the self-mixing interference technology of fiber laser, the self-mixing interference in the linear cavity fiber laser is theoretically analyzed through a four-mirror cavity model. The output power and frequency equation are deduced, and the behaviors of the laser under different optical feedback strengths are analyzed and simulated as well. The intensity of the laser is modulated by the length of the external cavity, and one fringe of the signal corresponds to the displacement of half wavelength of the target. Experimental setup is developed to validate the theoretical analysis. The obtained results provide both the theoretical and experimental basis for further studying self-mixing interferemetric sensing applications of fiber lasers.