Controllable growth

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Controllable growth of aluminum nanorods using physical vapor deposition

Controllable growth of aluminum nanorods using physical vapor deposition

Motivated by the technological demand for increased specific surface area and nanorods of the smallest diam- eter [7] and taking the demonstration of controllable growth one step further, we expect that a lower substrate temperature will further decrease the diameter of the nanorods by decreasing the diffusion of adatoms from the tops of nanorods even more than with O alone. As shown in Figure 3 the diameter of Al nanorods is re- duced to about 50 nm, which is an order of magnitude smaller than that in Figure 2b. In this case, we note that

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Controllable Growth of Ultrathin P doped ZnO Nanosheets

Controllable Growth of Ultrathin P doped ZnO Nanosheets

Figure 1a – d shows the typical SEM images of P-doped ZnO nanostructures grown at different oxygen flow rates. Clearly, the morphologies of ZnO nanostructures are changed dramatically with the variation of oxygen flow ratio. Without oxygen flow gas, ZnO nanoparticles are formed at the initial growth stage due to the high Zn vapor concentration; then, with the consumption of Zn vapor, small amounts ZnO nanowires begin to grow on the nanoparticles, resulting in the morphologies shown in Fig. 1a. When oxygen is introduced into the tube, ZnO nanosheets consisting of ribbon-like backbone and parallel nanoteeth are synthesized (Fig. 1b). The nano- teeth are grown epitaxially out of large ribbons with a length of tens of micrometers. When oxygen flow rate increases to 20 sccm, the width of nanoribbons in- creases, meanwhile an irregular shape is observed, indi- cating the growth direction changes to the transverse direction in Fig. 1c. The variation of growth direction for ZnO is attributed to the strain relaxation along the transverse direction, which results from P atoms inducing lattice distortion in ZnO. Further increasing oxygen flow rate promotes the continuous growth of nanoribbons along its transverse direction. TEM characterization identifies that the growth of nanorib- bons is along the 10 ½ 10 direction and enclosed by two large ± 1 ½ 210 surfaces, while the growth of nanoteeth is along the [0001] direction of ZnO [24]. To further con- firm the effect of oxygen flow gas, ZnO nanostructures without P 2 O 5 were grown at different oxygen flow rates,

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Controllable Growth of Ni Nanocrystals Embedded in BaTiO3/SrTiO3 Superlattices

Controllable Growth of Ni Nanocrystals Embedded in BaTiO3/SrTiO3 Superlattices

attracted more attention because their dielectricand fer- roelectric properties can be enhanced by controlling the lattice strain along the polarized direction [1-3]. The di- electric matrix with the embedded metal NCs has widely potential application in nonlinear optical and electronic device [4, 5]. Therefore, several methods have been con- sidered to fabricate the BTO and STO-based material, including sol-gel [6], reactive evaporation [7], rf-sputtering [8] and laser ablation methods [9]. However, the controllable fabrication of nanostructure remains the daunting challenge for many deposition methods. There is an excellent method referred to as self-organized growth, in which the strain would drive the three-dimensional (3D) island to form in the lattice mis- matched growth process [10, 11]. Especially for the fa- brication of quantum dot (QD) structures, the self-organized growth is greatly successful in semicon- ductor devices, such as InGaAs on GaAs [10], AlN on GaN [12]. Wu et al. have successfully fabricated Co:BTO and Ni:BTO composite film using self-organized method [13-15].

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Controllable growth of ZnO nanorod arrays with different densities and their photoelectric properties

Controllable growth of ZnO nanorod arrays with different densities and their photoelectric properties

Since the photoelectric response and charge carriers transport can be influenced greatly by the density and spacing of the ZnO nanorod arrays, controlling of these geometric parameters precisely is highly desirable but rather challenging in practice. Here, we fabricated patterned ZnO nanorod arrays with different densities and spacing distances on silicon (Si) substrate by electron beam lithography (EBL) method combined with the subsequent hydrothermal reaction process. By using the EBL method, patterned ZnO seed layers with different areas and spacing distances were obtained firstly. ZnO nanorod arrays with different densities and various morphologies were obtained by the subsequent hydrothermal growth process. The combination of EBL and hydrothermal growth process was very attractive and could make us control the geometric parameters of ZnO nanorod arrays expediently. Finally, the vertical transport properties of the patterned ZnO nanorod arrays were investigated through the microprobe station equipment, and the I-V measurement results indicated that the back- to-back Schottky contacts with different barrier heights were formed in dark conditions. Under UV light illumination, the patterned ZnO nanorod arrays showed a high UV light sensitivity, and the response ratio was about 10 4 . The controllable fabrication of patterned ZnO nanorod arrays and understanding their photoelectric transport properties were helpful to improve the performance of nanodevices based on them.

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Controllable Growth of the Graphene from Millimeter Sized Monolayer to Multilayer on Cu by Chemical Vapor Deposition

Controllable Growth of the Graphene from Millimeter Sized Monolayer to Multilayer on Cu by Chemical Vapor Deposition

observed in the middle of the graphene domain either monolayer or multilayer. In addition, the surface oxygen on the Cu surface may have existed as indicated by the EDS of the nanoparticle. The graphene nucleates on the oxide nanoparticle and begins to grow tuned from edge- attachment-limited growth to the diffusion (mass trans- port)-limited growth due to the surface oxygen that existed [19]. Consequently, the edge of the graphene contacted on the Cu surface is jagged, which is consist- ent with the results shown in Fig. 1 or Fig. 2 and the previous reports [19]. The hydrogen concentration is another key point in the growth process. The hydrogen concentration not only controls the layer number of the graphene domains, but also affects the shape of the gra- phene domains. In the growth process, the subsequent graphene layer continues nucleating on the oxide nano- particle and keeps on growing with the template of the bottom graphene by absorbing active carbon, and conse- quently, a multilayer graphene nucleation is formed. However, the growth speed of the top layer graphene is relatively low due to loss of contact with the catalytic substrate and affected by the hydrogen concentration heavily. In the condition of high hydrogen concentration, the growth speed on the bottom layer graphene is much higher due to more active carbon catalyzed by the Cu surface, while the top layer graphene nucleated on the oxide nanoparticle would be suppressed or even dis- appear due to the high hydrogen concentration at high temperature, and therefore, the large-sized single-crystal monolayer graphene can be obtained as shown in Fig. 4c and d. The corresponding experiment results are shown in Fig. 1. With low hydrogen concentration, the growth speed between the bottom layer and top layer graphene is relatively equal, so, multilayer graphene is obtained as displayed in Fig. 4e and f. To further confirm the

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Controllable growth of metallic nano helices at room temperature conditions

Controllable growth of metallic nano helices at room temperature conditions

consideration (in our case, 1728 K for Ni and 1234 K for Ag). We note that this homologous temperature is directly related to the thermally induced surface diffusion (adatom mobility) of the materials. 16 The uniformly structured and well separated Ni nano-helices grown using the heat-management system proposed here, see Figure 2(a), imply that they were grown within the zone 1 of the SZM. This gives an estimation of the maximum temperature reached during their growth of T g 0.2 T m ¼ 350 K. Meanwhile, the thicker and collapsed Ni

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Controllable preparation of Ni nanoparticles for catalysis of coiled carbon fibers growth

Controllable preparation of Ni nanoparticles for catalysis of coiled carbon fibers growth

The mass preparation of high-purity coiled carbon fibers (CCFs) remains challenging due to the high complexity and low controllability of reaction. In this work, a controllable growth of Ni particles was fulfilled by liquid phase reduction of nickel sulfate with hydrazine hydrate. The impacts of the reaction temperature, NaOH concentration, and reaction time on the particle size and purity were investigated. The as-deposited Ni particles were characterized by scanning electron microscopy and X-ray diffraction. In addition, these Ni particles were also applied in preparing high-purity CCFs both on graphite and ceramic substrates. The diameter of the as-grown carbon microcoil was about 500 nm, and the related growth mechanism was discussed.

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Bone scaffolds with controllable porosity

Bone scaffolds with controllable porosity

The limitations of the foam reticulation technique, described in Section 3.1.5, need to be overcome to enable its widespread use in producing bioscaffolds. One possible way to achieve this is to generate microporous struts that enhance the biologi- cal performance and hence significantly increase the regrowth rate of host tissue by providing cell attachment sites [2, 16]. Microporosity can be achieved by the incorporation of a porogen within the slurry as in solvent casting/particulate leach- ing [235, 236, 239] or freeze casting [256, 257]. The porogen is removed either during freeze drying or at the polymer burnout stage to leave a macroporous structure of microporous struts. The technique, outlined in Figure 3.5, follows that of foam reticulation with a freeze drying stage to generate micropores. Briefly, a template is coated with a porogen-containing biomaterial slurry. This is freeze dried to sublime the porogen, and the structure is then subjected to a controlled sintering protocol to enable complete polymer burnout and densification of the scaffold [267, 278]. As with freeze casting, control of the freeze drying parameters allows for the level of microporosity and micropore size to be varied [250, 253, 259, 260]. Meanwhile, template choice in replication techniques facilitates the production of a controllable macroporous structure [273, 276, 277]. Therefore combining these facilitates the generation of constructs of a predictable, hierarchical nature [267, 278].

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Towards Controllable Story Generation

Towards Controllable Story Generation

We proposed an analyze-to-generate framework that enables controllable story generation. The framework is generally applicable for many con- trol factors. In this paper, two instantiations of the framework are explored to control the end- ing valence and the storyline of stories. Exper- iments show that our framework enables human controls while achieving better coherence than an uncontrolled generation models. In the future, we will explore other control factors and better controllable generation models to adding the con- trol factors into the generated stories. The cur- rent analyze-to-generate framework is done in a pipeline fashion. We also plan to explore the joint training of the analyzer and the generator to im- prove the quality of both.

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Design of resolution/power controllable Asynchronous Sigma Delta Modulator

Design of resolution/power controllable Asynchronous Sigma Delta Modulator

The design of resolution/power controllable Asynchro- nous Sigma-Delta Modulator (ASDM) is successfully presented. Externally variable Current Regenerative Schmitt Trigger (CRST) is used to control the hysteresis, hence the switching rate and the resolution. It is achieved with externally variable control voltages of CRST. It is also possible to set the limit cycle frequency and resolution depending on the input signal slope, without corrupting the inband spectrum. This modula- tor is novel, as it is able to trade off power with reso- lution in converters. Proposed optimized Programmable Asynchronous Modulator (PAM) comprehensively re- ports the field programmability of ASDM. Results proved that the design is compact and power/perform- ance efficient. The proposed improved design is simple yet effective with a new concept implemented for ASDM. It can be a better solution over the sleep-mode circuits with faster wake-up times. Due to its off-chip dynamic power control feature, PAM is attractive for battery-operated IoT devices which uses ADC to achieve power optimization.

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Model Reduction for Controllable Systems

Model Reduction for Controllable Systems

We envision these two algorithms as part of a general scheme for dissipativity-preserving model reduction which, starting from a controllable and dissipative behavior B represented in DV, ON, state-space, kernel- or image form, produces any of these representations for a controllable and dissipative reduced-order behavior whose set of stationary trajectories contains a specified subset of the set of stationary trajectories of the original system. Research is being carried out in order to compute a kernel- or image representation of the reduced-order model.

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Unsupervised Controllable Text Formalization

Unsupervised Controllable Text Formalization

Unsupervised NLG has always been more challenging due to the fact that: (i) the output space is more complex and structured, making unsupervised learning more difficult, and (ii) metrics for evaluating NLG systems without reference output text are elusive. Recently, Artetxe et al. (2017) and Lample, Denoyer, and Ranzato (2017) have proposed ar- chitectures for unsupervised language translation with un- supervised autoencoder based lexicon induction techniques. This approach primarily focuses on cross-lingual transfor- mation and requires multiple unlabeled corpora from differ- ent languages. It can not trivially be extended to our setup to achieve a controllable text-transformation goal within a single language, and further there is no notion of control in language translation. A notable work by Hu et al. (2017) discusses controllable generation; the system takes control parameters like sentiment, tense etc., and generates random sentences conforming to the controls. However, this system, unlike ours, does not transform a given input text.

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An Algorithm for Maximizing the Controllable Set for Open-Loop Unstable Systems under Input Saturation

An Algorithm for Maximizing the Controllable Set for Open-Loop Unstable Systems under Input Saturation

Figure 3 shows the comparison of the three controllable sets: the maximal controllable set, the controllable set under the Lyapunov descent condition, and the controllable set inside the linear region. As we can see from Fig. 3, the controllable set under the Lyapunov descent condition and the controllable set inside the linear region are contained in the maximal ellipsoidal controllable set found by our approach.

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Air Spring and Magnetorheological Damper: an Integrated Solution for Vibration Control

Air Spring and Magnetorheological Damper: an Integrated Solution for Vibration Control

These materials demonstrate changes in their rheological behaviour in presence of an applied magnetic field [3]. In the recent years MR fluids have attracted considerable interest because they can provide a simple and rapid response interface between electronic controls and mechanical systems [4 – 7]. The initial discovery and development of MR fluids and devices can be credited to Rabinow at the US National Bureau of Standards in the late 1940s [8 – 10]. These fluids are suspensions of micron- sized, magnetizable particles in an appropriate carrier liquid. Normally, MR fluids are free-flowing liquids having a consistency similar to that of motor oil. However, in the presence of an applied magnetic field, the particles acquire a dipole moment aligned with the external field that causes particles to form linear chains parallel to the field. This phenomenon can solidify the suspension and restrict the fluid movement. Consequently, yield stress is developed. The degree of change is related to the magnitude of the applied magnetic field and can occur in only a few milliseconds. The primary advantage of MR fluids stems from their large and controllable dynamic yield stress due to the high magnetic energy density that can be established in the fluids. The behaviour of the MR fluid is divided into pre-yield and post-yield regions, depending on whether the fluid is stressed below or above a critical yield stress value. The post-yield behaviour is non-Newtonian and the apparent viscosity of the fluid increases due to the increase in the yield stress with an external magnetic field.

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Metalorganic chemical vapor deposition growth of InAs/GaSb type II superlattices with controllable Asx
              Sb1 xinterfaces

Metalorganic chemical vapor deposition growth of InAs/GaSb type II superlattices with controllable Asx Sb1 xinterfaces

In situ reflectance can give us useful information of the growth surface during the epitaxy. Figure 1 shows the in situ reflectance at 633 and 951 nm of a 100-period InAs/GaSb SL sample. Fabry-Perot (FP) oscillations are visible in both reflectance curves during the SL growth. The oscillation amplitude of the 951-nm reflectance damps gradually with the growth time due to the gradu- ally increased absorption of the SL material. Using a VI mode [21], the period of the SL structure extracted from this reflectance curve is 7.5 nm. For the 633-nm reflectance signal, the FP oscillation damps very quickly since the absorption of the SL material is significant at 633 nm. However, a high frequency and uniform oscilla- tion can be clearly observed on the 633-nm reflectance curve, which arises from the different reflectance of InAs and GaSb. It is known that the intensity of the mirror-reflectance signal is related to the morphology of the growth surface; thus, the flat reflectance curve with the reflectance above 0.4 indicates rather smooth growth surface during the epitaxy of the SL structure.

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Counterfactual thinking about controllable events

Counterfactual thinking about controllable events

Gavanski and Wells (1989) found a correspondence between the normality of the outcome of a scenario and the events people come to mutate. Likewise, Bouts, Spears, and Van der Pligt (1992) showed that people are more likely to focus on negative antecedent events to undo negative outcomes and on positive antecedent events to undo positive outcomes. In our second experiment, we also tested an alternative hypothesis, that the effects of varying appropriateness on the mutability of controllable events were due instead to a valence correspondence (see also Klauer, Jacobsen, & Migulla, 1995). The outcome of the scenario that we used in the first experiment and the outcome of the scenario used by Girotto et al. (1991) were negative. It is possible that inappropriate events (such as going into a bar for a beer) are seen as negative and that appropriate events (such as visiting your parents) are seen as positive. Therefore, in our experiment, participants might have been focusing on the inappropriate event in- stead of the appropriate event because it was negative, as was the outcome of the scenario. In order to rule out this potential explanation of the results of our experiment, we used not only scenarios with negative outcomes, but also scenarios with positive outcomes. If participants were fo- cusing on inappropriate events in the previous experiment because of a valence correspondence effect, we expected that they would instead focus on appropriate events, given a scenario with a positive outcome. However, if this va- lence correspondence explanation did not hold, we ex- pected that inappropriate events would be mutated more often than appropriate events for both negative (failure) outcomes and positive (success) outcomes.

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The M/M/c/N/K Interdependent Queueing Model with Controllable Arrival Rates and Reverse Balking

The M/M/c/N/K Interdependent Queueing Model with Controllable Arrival Rates and Reverse Balking

Along with several other assumptions, it is customary to consider that the arrival and service processes are independent. However in many particular situations, it is necessary to consider that the arrival and services processes are inter dependent. A queueing model in which arrivals and services are correlated is known as interdependent queuing Model. Much work has been reported in the literature regarding interdependent standard queuing model with controllable arrival rates.K.Srinivasa Rao,Shobha and P.Srinivasa Rao [3] have discussed M/M/1/ interdependent queuing model with controllable arrival rates. A.Srinivasan and M. Thiagarajan [4,5,6,7] have analysed M/M/1/K interdependent queuing model with controllable arrival rates, M/M/c/K interdependent queuing Model with controllable arrival rates M/M/c/K/N interdependent queuing Model with controllable arrival rates balking, reneging and spares and have analysed M/M/c/ /N loss and delay queueing system with interdependent queuing Model with controllable arrival rates and no passing. B.Antline Nisha and M.Thiagarajan [8] have discussed M/M/1/K/N interdependent retrial queuing Model with controllable arrival rates. Recently S.Sasikala and M.Thiagarajan [9] have studied the M/M/c/N interdependent queuing Model with controllable arrival rates and reverse balking.

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Novel Design of n-bit Controllable Inverter by Quantum-dot Cellular Automata

Novel Design of n-bit Controllable Inverter by Quantum-dot Cellular Automata

In order to implement controllable inverter circuit, we used the proposed 2-input XOR gates and 2-input XOR gate features in inverter operations. In the first state, two 2-input XOR gates were located next to each other. Then we connected one of the input gate pins to two input data, and other pins were connected to each other and used as controller input. In this circuit, if the control input was loaded on zero, the output remained the same value, and if the control input was loaded on one, the output was inverted. The layout of 2-bit controllable inverter in QCA is presented in Figure 10.

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Controllable Abstractive Summarization

Controllable Abstractive Summarization

work using recurrent networks (Nallapati et al., 2016; See et al., 2017; Paulus et al., 2017). We borrow intra- attention from (Paulus et al., 2017) and expand it to multi-hop intra-attention inspired by multi-hop source attention from (Gehring et al., 2017). To facilitate copying input entities, we share the word represen- tations between encoder and decoder (Paulus et al., 2017), and also rely on BPE tokenization (Sennrich et al., 2016b). This combination allows us to forgo an additional pointer mechanism unlike (Paulus et al., 2017; See et al., 2017; Nallapati et al., 2016). Un- like (Paulus et al., 2017), we did not explore training objectives and maximized the likelihood of the train- ing summaries given the source document. Our model is amenable to RL, but this aspect is largely orthogonal to our main goal, i.e. controllable summarization. 3.2 Controllable Text Generation

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Nucleation and aggregative growth of palladium nanoparticles on carbon electrodes : experiment and kinetic model

Nucleation and aggregative growth of palladium nanoparticles on carbon electrodes : experiment and kinetic model

Investigations to improve knowledge in this area present a number of challenges. A major issue is that electrochemical nucleation sites of widely different character are randomly distributed on a solid substrate, and if there is a large number of nuclei and NPs, the interactions between them can be complex. There are many concepts involved in describing electrochemical nucleation and growth processes, including time-lag 14 , nucleation exclusion zone 15 and the critical nuclei size 16 ,

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