The current radicalism and declining legitimacy of our entire system have placed social work in special jeopardy. Clients, students, and young practitioners have challenged both the relevance and commitment of social ...
The current radicalism and declining legitimacy of our entire system have placed social work in special jeopardy. Clients, students, and young practitioners have challenged both the relevance and commitment of social workers. The author describes six emerging social action roles that provide an opportunity for the ioint development by clients and professionals of new participatory institutions.
Muscle actin filaments labeled with rhodamine-phalloidin were observed to move on the surface coated with a crude extract of pollen tubes of Lilium longiflorum with an average velocity of 1.99 +/- 0.55-mu-m/sec. The m...
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Muscle actin filaments labeled with rhodamine-phalloidin were observed to move on the surface coated with a crude extract of pollen tubes of Lilium longiflorum with an average velocity of 1.99 +/- 0.55-mu-m/sec. The movement required both Mg2+ and ATP. These results indicate that the extract of pollen tubes contains a myosin-like translocator.
Determining appropriate road drainage grate installation intervals requires an equation for estimating the flow intercepted by each grate inlet and its interception efficiency. In this study, 720 experiments were perf...
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Determining appropriate road drainage grate installation intervals requires an equation for estimating the flow intercepted by each grate inlet and its interception efficiency. In this study, 720 experiments were performed using a hydraulic model to estimate the flow intercepted by a grate inlet on a road. The flow calculation considered the number of lanes (2-4), longitudinal slope of the road (2-10%), transverse slope of the gutter (2-10%), and design capacity (up to 30 years of rainfall). The experimental results revealed that the flow intercepted by a grate inlet increased with increasing transverse slope of the gutter or the inlet length, thereby increasing its interception efficiency. Intercepted flow estimation equation was derived by regression analysis, and the derived equation was found to be more accurate than an existing empirical equation. The derived equation can thus be used to determine the installation of drainage grate inlets more effectively.
The bombardment of a surface by 1–25 keV primary ions causes the upper atomic layers to be “sputtered” or stripped off. Most of the material leaves as neutral atoms or molecules, but a small fraction is ejected as ...
The bombardment of a surface by 1–25 keV primary ions causes the upper atomic layers to be “sputtered” or stripped off. Most of the material leaves as neutral atoms or molecules, but a small fraction is ejected as positive or negative ions. These secondary ions can then be characterized by a mass spectrometer to provide an analysis of that portion of the material sampled by the primary ion beam. At any one instant, the excitation volume is bounded by the primary ion beam periphery (1–300 μm) and extends to a depth of 5–50 Å depending on experimental conditions. By mass spectrometrically monitoring one or several masses, the analyst can obtain isotopic and concentration in-depth profiles of the sample constituents. Alternatively he can obtain a complete mass spectrum as the primary beam erodes the sample. Control and localization of the primary ion beam erosion permits chemical analysis with lateral x , y resolutions of approximately 1 μm, the examination of fractional surface monolayers, an in-depth analysis with better than 100 Å resolution, and the acquisition of secondary ion images. The mass spectrometer provides elemental coverage from hydrogen to uranium, isotopic characterization and detection limits of 10 -15 −10 -19 g , depending on the element under consideration. This paper will discuss the production of secondary ions, the various types of instrumentation used, and applications of the ion probe technique.
A waveguide occupies a domain in an (n + 1)-dimensional Euclidean space which has several cylindrical outlets to infinity. Three classes of waveguides are considered: those of quantum theory, of electromagnetic theory...
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A waveguide occupies a domain in an (n + 1)-dimensional Euclidean space which has several cylindrical outlets to infinity. Three classes of waveguides are considered: those of quantum theory, of electromagnetic theory, and of elasticity theory, described respectively by the Helmholtz operator, the Maxwell system, and the system of equations for an elastic medium. It is assumed that the coefficients of all problems stabilize exponentially at infinity, to functions that are independent of the axial variable in the corresponding cylindrical outlet. Each row of the scattering matrix is given approximately by minimizing a quadratic functional. This functional is constructed by use of an elliptic boundary value problem in a bounded domain obtained by cutting the cylindrical outlets of the waveguide at some distance R. The existence and uniqueness of a solution is proved for each of the three types of waveguides. The minimizers converge exponentially fast as functions of R, as R -> infinity, to rows of the scattering matrix.
A novel Zr-substituted polyoxometalate（POM） H2K3[Na6（H2O）9][Zr3Na3O3（H2O）3-（GeW9O（34））2]·12H2O（1） has been made under hydrothermal conditions. 1 was characterized by infrared spectrum, thermogravimetr...
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A novel Zr-substituted polyoxometalate（POM） H2K3[Na6（H2O）9][Zr3Na3O3（H2O）3-（GeW9O（34））2]·12H2O（1） has been made under hydrothermal conditions. 1 was characterized by infrared spectrum, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Crystal data are： H（50）O（95）Na9K3Ge2Zr3W（1）8, hexagonal space group P63/mmc, a = 15.2251（6）, b = 15.2251（6）, c = 25.035（2） , V = 5025.7（6） 3, Z = 2, Dc = 3.716 mg/m3, μ = 21.648 mm（-1）, F（000） = 4726, the final R = 0.0259 and w R = 0.0647 for 1487 observed reflections with I 2σ（I）. Single-crystal X-ray structure analysis reveals that 1 exhibits a 3-dimensional framework structure based on Zr3Na3-substituted polyanions [Zr3Na3O3（H2O）3（GeW9O（34））2]（11-） and [Na6（H2O）9]（6＋） clusters building blocks. UV-Vis spectrum indicates that 1 is a wide-gap semiconductor. In addition, the proton-conducting property of 1 was also investigated.
Detailed analysis of a bored pile lateral load test is required to generate the family of nonlinear lateral load-displacement curves known as "p-y" curves. Current methods of calculating these curves from te...
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Detailed analysis of a bored pile lateral load test is required to generate the family of nonlinear lateral load-displacement curves known as "p-y" curves. Current methods of calculating these curves from test pile data may not make full use of all data (inclinometer, strain gage, head deflection) available. The method outlined below incorporates all available data in formulating a mathematical model of the pile behavior from which p-y curves may be derived.
This study investigated changes in dissolved organic matter (DOM) properties within urban sanitary sewers influenced by groundwater infiltration and excessive rainfall-derived inflow and infiltration (RDII). It employ...
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This study investigated changes in dissolved organic matter (DOM) properties within urban sanitary sewers influenced by groundwater infiltration and excessive rainfall-derived inflow and infiltration (RDII). It employed optical indices and fluorescence excitation-emission matrix-parallel factor analysis (PARAFAC) coupled with self-organizing map (SOM) to compare DOM characteristics during wet weather flows (WWFs) and dry-weather flows (DWFs). Sampling sites impacted by RDII were identified based on flowrate. Optical indices and PARAFAC components (C1-C4) -C4) were used to differentiate DOM properties between DWFs and WWFs. In WWFs, E2/E3 2 /E 3 and S 350-400 increased, while spectral ratio (SR) R ) decreased, indicating a shift towards smaller organic matters. Reduced fluorescence and humidification indices suggested the input of fresher/terrestrial organic matters. C3 and C4 exhibited significant distinctions, showing increased C3 and decreased C4 levels. The PARAFAC-SOM modeling further illustrated that water samples in the urban sewer system could be categorized based on the dominance of DOM properties. Principal component analysis revealed separation between DWF and WWF samples in principal component 1 (PC1), associated with molecular size. PC2 was linked to microbial activity in WWFs. Notably, DWF samples from the NY-11 site shifted to the positive side of the PC1 axis, while their corresponding WWF samples moved to the negative side.
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