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The present research tested the effectiveness of adding an interpersonal, interactive, experiential training programme to addictions treatment that enhances motivation, cognitive-behavioural coping skills, social support, and group cohesiveness. The research was conducted in a co-educational, long-term residential treatment facility for addictive disorders (alcohol and other substances, sexual addiction, eating disorders, compulsive shopping, and gambling) and concomitant psychiatric diagnoses. The added training is co-created by participants. They choose challenging situations important in their lives that are played out as ‘movies’ in which they play and experience all the parts. Motivation for change, skills to implement positive changes, self-efficacy, empathy, positive support, and group cohesiveness are rooted in their own experiences and the feedback they receive from others, as they behave in empowering and disempowering ways. The training resulted in significant increases in empowering communication, self-esteem and quality of group life in the treatment group and in the family. Many of these results have large effect sizes and are consistent with the findings from prior studies. The results obtained in this study suggest that Say It Straight training can be an effective addition to the treatment of addictions in residential treatment. Future research is needed to determine the long-term effects of this training on relapse.

Effectiveness of Say It Straight communication training as a treatment component was evaluated with 36 mothers in residential chemical dependency treatment. All were indigent, 32 had previous criminal offenses and 14 were on probation or parole at the time of treatment. Self-reported, disempowering behaviors showed highly significant decreases after SIS training (p < 0.001). Empowering behaviors, quality of family and group life showed significant increases (p = 0.001, p = 0.008, p = 0.015, respectively). Self-esteem, assessed with one group of eight mothers, showed a highly significant increase after training (p = 0.009). Statistically significant differences between mothers in treatment an average of 40 days compared to those in treatment 141 days prior to training disappeared after 10-16 hours of training, although the latter group also showed positive changes. Reports regarding training effectiveness were very positive. Results indicate this training is an important addition to treatment and ...

An important issue in field emission vacuum microelectronics is the stability of the field emitters with the residual ambient gas. Particularly important is that the field emitter tips made of refractory metals like molybdenum, niobium and tungsten are susceptible to oxidation. The corresponding metal oxides are insulating and adversely affect the emission current characteristic by increasing the width of the effective tunneling barrier. With this perspective, we studied iridium oxide field emitters to evaluate the characteristics of conductive oxide tips. We studied the field emission characteristics of iridium and thermally prepared iridium oxide field emitters using field emission microscopy and current–voltage measurements. We found that, upon oxidation, the voltage required to achieve the desired emission current desire dropped significantly. In addition, oxidation led to a decrease of emission current fluctuations. The development of stable conductive oxide field emitters should improve the performa...

A simple instrument to determine field emission tip work functions and shape functions from simultaneous current–voltage (I–V) characteristics and field emission energy distributions of field emitter tips and tip arrays is described. This instrument uses a cylindrical energy analyzer with a few correcting elements to simulate a hemispherical analyzer and provides a low cost and more compact alternative to a commercial hemispherical spectrometer. I–V curves and energy distributions may be automatically obtained as a function of time to study field emission tip degradation with usage and/or exposure to gases of interest.

SUMMARY This paper reviews the impact of Virginia Satir's communication work as reflected in the Say It Straight program for prevention of destructive behaviors and promotion of wellness with young people, parents and other adults in many settings such as classrooms, student support groups, juvenile detention, cooperative learning teams, chemical dependency treatment and prison. Results of 13 years of research and training with the Say It Straight program show the applicability of Virginia's work in preventing alcohol/drug related school suspensions, juvenile criminal offenses, precocious sexuality/pregnancy, and in promoting good communication skills, self-esteem, positive relationships, and quality of life.

A communication skills program, 'Say It Straight' (SIS) training, was conducted with 2781 students in the 3rd-12th grades and 227 pare- and other adults ling in high-risk environments. Ninety-six teachers, counselors, nurses, other school personnel and community volunteers who were trained in 44 day workshops, implemented SIS training with students in classrooms and in student support groups. Some also implemented SIS training with parents, other community members and in multi-family groups. All grades showed significant increases in behavioral intentions to implement constructive decisions in difficult situations and feel more at ease doing 50 (P < 0.048 to P < 0.001). Analysis by gender showed highly significant increases for both males and females (P < 0.010 to P < 0.001), except for a small sample of those in the third gnde. Adults reported significant i- in effective communications and quality of life (P < 0.010 to P < 0.01) and significant decreases in blaming or being sarcastic, placating being pas...

The work function of hydrogen-terminated polycrystalline diamond films deposited by electrophoresis on molybdenum was studied using ultraviolet photoelectron spectroscopy with 21.2 eV photons for average grain sizes ranging from 0.32 to 108 μm. The work function has a maximum of about 5.1 eV at 0.32 μm, then decreases with increasing grain size to a minimum of about 3.2 eV at an average grain size of about 4 μm and then increases to a value of about 4.8 eV at a grain size of 108 μm. The results are consistent with a model in which the work function is controlled by the work function of single crystal diamond (111) at the larger grain sizes, graphitic carbon at the smaller grain sizes, and by a negative electron affinity that increases with decreasing grain size due to defects near diamond (111) crystallite edges for the intervening grain sizes. The large change in work function (almost a factor of 2) could be useful to make conductors with different work functions for microelectronic gate structures.

The emission current in a molybdenum field emission array can decrease by 50% in 1000 s at an oxygen pressure of 10−6 Torr. To overcome this disadvantage of molybdenum microtips, the effectiveness of dynamic surface cleaning has been investigated in a single-aperture gated-diode configuration. For dynamic surface cleaning, tip surface oxide buildup is balanced by tip oxide removal due to sputtering by ions created in ionizing collisions with field-emitted electrons. The present results demonstrate stable dynamic cleaning with clean and partially oxidized molybdenum tips for currents ranging from 10−11 to 10−9 A with oxygen exposures of up to 1000 L. For currents above 10−9 A, ion bombardment causes the tip shape to become unstable leading to failure with increasing oxygen exposure.

The present research tested the effectiveness of adding an interpersonal, interactive, experiential training programme to addictions treatment that enhances motivation, cognitive-behavioural coping skills, social support, and group cohesiveness. The research was conducted in a co-educational, long-term residential treatment facility for addictive disorders (alcohol and other substances, sexual addiction, eating disorders, compulsive shopping, and gambling) and concomitant psychiatric diagnoses. The added training is co-created by participants. They choose challenging situations important in their lives that are played out as 'movies' in which they play and experience all the parts. Motivation for change, skills to implement positive changes, self-efficacy, empathy, positive support, and group cohesiveness are rooted in their own experiences and the feedback they receive from others, as they behave in empowering and disempowering ways. The training resulted in significant increases in empowering communication, self-esteem and quality of group life in the treatment group and in the family. Many of these results have large effect sizes and are consistent with the findings from prior studies. The results obtained in this study suggest that Say It Straight training can be an effective addition to the treatment of addictions in residential treatment. Future research is needed to determine the long-term effects of this training on relapse.

The thermal stability and the resiliency of molybdenum carbide field-emission tips deposited at room temperature by electrophoresis have been studied. The field emission from Mo2C films deposited on Mo tips does not change after being heated to 800 °C while exposed to 360 L of air, although MoO2, MoO3, and possibly MoO, are present in the films. The field-emission thresholds agree with photoelectric work functions determined from photoelectron spectroscopy measurements of similarly grown flat samples. These films are found to exist in three distinct phases as a function of temperature after formation by room-temperature electrophoresis. From room temperature to 500 °C, MoO3 is the dominant oxide, from 500 to 775 °C, MoC2 is the dominant oxide, and above 825 °C both oxides have virtually disappeared.

We report a decrease in field emission threshold from 3.8 to 3.4 eV for room temperature electrophoresis grown polycrystalline diamond films on molybdenum tips as the diamond average grain size increases from 0.25 to 6 μm. The field emission thresholds agree with photoelectric work functions determined from photoelectron spectroscopy measurements of similarly grown flat samples. In addition, diamond surface states are observed at 0.4, 0.9, and 1.8 eV above the valence band. The results are consistent with an increasing negative electron affinity with grain size due to increased surface hydrogen bonding and with perhaps a contribution from surface defect states.

The effect of thermal growth conditions on the morphology and surface work function of iridium oxide thin films grown by annealing Ir thin films in an O2 ambient is presented. The samples were analyzed using x-ray diffraction, x-ray photoelectron spectroscopy, atomic force microscopy, and photoelectric work function measurements. It is found that, with increasing temperature, IrO2 changes from (110) oriented to a mixture of (110) and (200) during the oxide growth. This is manifested as a sharpening of the photoelectric energy distributions at 800 °C. The surface work function was determined to be 4.23 eV using ultraviolet photoelectron spectroscopy. X-ray photoelectron spectroscopy analysis shows that IrO2 starts to form at 600 °C accompanied by surface roughening. Annealing the Ir film at 900 °C in O2 ambient leads to almost complete desorption of the film.

Oxidation of emitter surfaces can be a serious problem for Mo field emitter arrays. We studied the oxidation and related changes in the electronic properties of Mo thin films as a function of annealing temperature. Experiments were done on Mo thin films prepared on Si and sodalime glass substrates. These films were thermally oxidized and characterized using a variety of techniques including x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and thermal desorption spectroscopy (TPD) methods. For films oxidized below 400°C, partial oxidation was observed, with MoO3(110) being the principal oxide phase. However, at a temperature of 500°C and above, oxidation of the film was complete. Electrical characteristics of the films undergo a rapid transition from semiconductive to highly insulating at temperatures between 475 to 500°C. Temperature programmed desorption spectra showed that the oxides are stable at elevated temperature with only a principal O2 desorption peak at approximately 786°C.

Field emission current-voltage characteristics and simultaneous field emission electron energy distributions have been measured using single tip gate diodes. An energy distribution is generated at each step of a current-voltage characteristic using a compact low-cost simulated hemispherical energy analyzer. A PC programmed with graphics-based data acquisition software is used for data acquisition and control. The PC is connected to a CAMAC crate and a picoammeter through a GPIB interface. The picoammeter measures the current leaving the tip and the field emission electrons are energy analyzed, detected and processed in the CAMAC crate. The CAMAC crate also sends control voltages. to the gate anode and the energy analyzer. This apparatus was used to measure tip work functions and Fowler-Nordheim tip shape parameters for Mo and IrO2 field emission tips. Work function measurements from field emission tips are compared to photoelectric work function measurements from flat surfaces.

Molybdenum carbide and diamond films were deposited at room temperature by dielectrophoresis on molybdenum foil and field emission tips. Films deposited on flat surfaces were characterized with XPS, UPS and SEM. Field emission Fowler-Nordheim current-voltage characteristics and electron energy distribution measurements were obtained using films deposited on field emission tips as part of a single aperture gated diode in a VG ESCALAB II system. Molybdenum trioxide was present after molybdenum carbide deposition at room temperature on all samples. At a temperature of about 650 °C, the dominant oxide changes to molybdenum dioxide. At about 800 °C, the oxygen content of the films significantly decreases and molybdenum carbide with significant graphite content remains. The UPS data for these samples were obtained at different annealing temperatures and a number of photon energies to determine photoelectric work functions for molybdenum trioxide, molybdenum dioxide and molybdenum carbide. The same kind of data was obtained for diamond deposited on molybdenum and molybdenum carbide coated foils and field emission tips.

We report a significant decrease in the photoelectric threshold of chemical vapor deposition grown diamond films as the fraction of sp3 carbon to sp2 plus sp3 carbon in the films decreases. Raman spectroscopy and x-ray photoelectron spectroscopy are used to characterize the different forms of carbon in the films and the sp3/(sp2 + sp3) carbon fraction at the surface. We observe a decrease in the photoelectric threshold from 4.5 eV to 3.9 eV as the sp3/(sp2 + sp3) carbon fraction at the surface decreases from 71% to 55%. Ultraviolet photoelectron spectroscopy of the films shows that they have a negative electron affinity surface. Therefore, the work function of the films decreases from 4.5 eV to 3.9 eV. We propose that the decrease in photoelectric threshold is due to a decrease in the band gap of sp2-sp3 carbon networks at the grain boundaries. The observed decrease in photoelectric threshold can be used to tailor the electronic properties of diamond films for specific applications.

Boron doped polycrystalline diamond films grown on p-type single-crystal Si substrates using chemical vapor deposition with a gas mixture of hydrogen, methane and diborane were characterized with scanning electron microscopy, X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, Raman spectroscopy and photoelectric current measurements. The energy distributions are not sensitive to boron doping for diborane concentrations from 0 to 4.75 ppm, although the boron doping modifies the surface morphology and the photoemission intensity. The photoemission intensity is high where the microcrystalline content is highest (at diborane concentrations of 2.91 and 4.75 ppm. The photoelectric threshold is found to be at 4.38 eV, in agreement with earlier measurements. The present results are characteristic of valence band emission at 4.38, 4.63, 4.92, 5.12 and 5.30 eV for incident photons between 4.87 and 5.63 eV.

A theory of electron-impact excitation of atoms in which fine structure is included as a perturbation is presented in detail. Hyperfine structure is included in the target atom but neglected in the electron-atom interaction. Expressions for electron-photon angular-correlation parameters and scattering cross sections are derived in terms of products of complex scattering amplitudes, with emphasis on electron-sodium excitation. Examples are given in which zero-field quantum beats may be observed in electron-photon angular-correlation and differential-cross-section measurements. Some of the interference terms are only observable in angular-correlation experiments. Examples are also given of partial cross sections for electron-impact excitation of state-to-state hyperfine levels in terms of direct- and exchange-scattering amplitudes plus additional terms due to the inclusion of fine-structure effects. The expressions given allow a comparison between the various possible scattering experiments.

Close-coupling calculations of $e$-He scattering in the region 30-70 eV reveal structures in the $n=2^{1,3}S$ excitation cross sections between 30 and 50 eV, in agreement with recent experiments. The structures are attributed to open-channel compound-state formation. Additional structures are also predicted at both higher and lower energies. These calculations suggest that temporary negative-ion formation should be considered as a mechanism for triplet excitation.

The energy-differentiated electron impact spectra of ${\mathrm{H}}_{2}$ has been studied near the ${\mathrm{H}}_{2}^{+}$ threshold in a transmission experiment. Eleven structures with spacings characteristic of the $^{2}\ensuremath{\Sigma}_{\mathrm{g}}$ state of ${\mathrm{H}}_{2}^{\ensuremath{-}}$ have been found starting at about 13.6 eV. Five of these structures are above the ${\mathrm{H}}_{2}^{+}$ threshold. It is suggested that some of the structure previously found in the cross section for the production of ${\mathrm{H}}_{2}^{+}$ near threshold is due to autoionization of this state of ${\mathrm{H}}_{2}^{\ensuremath{-}}$.

The performance of college students in introductory physics courses has been studied using conventional examination procedures as a measure of content mastery. Retesting over the same physics content using repeatable equivalent examinations results in a significant increase in the students mastery of physics. Students greatly preferred this type of examination procedure.

We have observed a broad $P$-wave resonance at about 50 eV primary energy in the angular distribution of electrons scattered after excitation of the ${2}^{3}S$ state of helium. The resonance has a width of about 15 eV and affects the differential excitation cross section by more than 3 orders of magnitude. It is suggested that this resonance is associated with the temporary formation of triply excited states of the negative helium ion.

The principle of detailed balance is used to show that at a maximum in an electron excitation cross section, due to a very‐short‐lived negative ion resonance (10−14–10−16 sec), the electron deexcitation cross section can be significantly smaller than the electron excitation cross section. Using experimental estimates of the various necessary parameters, it is suggested that population inversion may be maintained or enhanced in pure gas lasers by electron bombardment at negative ion resonance energies.