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The neutron's lifetime is a critical parameter in the standard model. Its measurements, particularly measurements using both beamline and ultracold neutron storage techniques, have revealed significant tension. In this work, we review the status of the tension between various measurements, especially in light of the insights provided by the β -decay correlation measurements. We revisit the lifetime measurement in a material storage chamber, dominated by losses from scattering off the walls of the storage chamber. The neutron energy spectra and associated uncertainties were, for the first time, well-characterized using storage data alone. Such models have applications in the extraction of the mean time between wall bounces, which is a key parameter for neutron storage disappearance experiments in search of neutron oscillation. A comparison between the loss model and the number of neutrons stored in a single chamber allowed us to extract a neutron lifetime of τ n * = 880 (+ 158 / − 78) stat. (+ 230 / − 114) sys. s   (68.3 %   C. I.) . Though the uncertainty of this lifetime is not competitive with currently available measurements, the highlight of this work is that we precisely identified the systematic sources of uncertainty that contribute to the neutron lifetime measurements in material storage bottles, namely from the uncertainty in the energy spectra, as well as from the storage chamber surface parameters of the Fermi potential and loss per bounce. In doing so, we highlight the underestimation of the uncertainties in the previous Monte Carlo simulations of experiments using the technique of ultracold neutron storage in material bottles. [ABSTRACT FROM AUTHOR]

The influence of Ar + SiH4 + O2 plasma formulation on the phase composition and optical properties of amorphous SiOx films with silicon nanoclusters obtained using PECVD with DC discharge modulation was studied. Using a unique technique of ultrasoft X-ray emission spectroscopy, it was found that at a 0.15 mol.% plasma oxygen content, amorphous silicon a-Si films are formed. At a high oxygen content (≥21.5 mol.%), nanocomposite films based on SiOx silicon suboxide containing silicon nanoclusters ncl-Si are formed. It was found that the suboxide matrix consists of a mixture of SiO1.3 and SiO2 phases, and the average oxidation state x in the SiOx suboxide matrix is ~1.5. An increase in the concentration of O2 in the reactor atmosphere from 21.5 to 23 mol.% leads to a decrease in ncl-Si content from 40 to 15% and an increase in the average oxidation state x of SiOx from 1.5 to 1.9. In this case, the suboxide matrix consists of two phases of silicon dioxide SiO2 and non-stoichiometric silicon oxide SiO1.7. Thus, according to the experimental data obtained using USXES, the phase composition of these films in pure form differs in their representation in both random coupling and random mixture models. A decrease in the ncl-Si content of SiOx films is accompanied by a decrease in their sizes from ~3 to ~2 nm and a shift in the photoluminescence band from 1.9 eV to 2.3 eV, respectively. [ABSTRACT FROM AUTHOR]

SUMMARY: Floral scent plays a crucial role in the reproductive process of many plants. Humans have been fascinated by floral scents throughout history, and have transported and traded floral scent products for which they have found multiple uses, such as in food additives, hygiene and perfume products, and medicines. Yet the scientific study of how plants synthesize floral scent compounds began later than studies on most other major plant metabolites, and the first report of the characterization of an enzyme responsible for the synthesis of a floral scent compound, namely linalool in Clarkia breweri, a California annual, appeared in 1994. In the almost 30 years since, enzymes and genes involved in the synthesis of hundreds of scent compounds from multiple plant species have been described. This review recapitulates this history and describes the major findings relating to the various aspects of floral scent biosynthesis and emission, including genes and enzymes and their evolution, storage and emission of scent volatiles, and the regulation of the biochemical processes. Significance Statement: This reviews describes our existing knowledge of how flowers produce and emit volatile compounds, and discusses the reasons for why research in this area lagged behind other topics in plant biochemistry. [ABSTRACT FROM AUTHOR]

Developing high-performance Si-based light-emitting devices is the key step to realizing all-Si-based optical telecommunication. Usually, silica (SiO2) as the host matrix is used to passivate silicon nanocrystals, and a strong quantum confinement effect can be observed due to the large band offset between Si and SiO2 (~8.9 eV). Here, for further development of device properties, we fabricate Si nanocrystals (NCs)/SiC multilayers and study the changes in photoelectric properties of the LEDs induced by P dopants. PL peaks centered at 500 nm, 650 nm and 800 nm can be detected, which are attributed to surface states between SiC and Si NCs, amorphous SiC and Si NCs, respectively. PL intensities are first enhanced and then decreased after introducing P dopants. It is believed that the enhancement is due to passivation of the Si dangling bonds at the surface of Si NCs, while the suppression is ascribed to enhanced Auger recombination and new defects induced by excessive P dopants. Un-doped and P-doped LEDs based on Si NCs/SiC multilayers are fabricated and the performance is enhanced greatly after doping. As fitted, emission peaks near 500 nm and 750 nm can be detected. The current density-voltage properties indicate that the carrier transport process is dominated by FN tunneling mechanisms, while the linear relationship between the integrated EL intensity and injection current illustrates that the EL mechanism is attributed to recombination of electron–hole pairs at Si NCs induced by bipolar injection. After doping, the integrated EL intensities are enhanced by about an order of magnitude, indicating that EQE is greatly improved. [ABSTRACT FROM AUTHOR]

Despite bulk crystals of silicon (Si) being indirect bandgap semiconductors, their quantum dots (QDs) exhibit the superior photoluminescence (PL) properties including high quantum yield (PLQY > 50%) and spectral tunability in a broad wavelength range. Nevertheless, their low optical absorbance character inhibits the bright emission from the SiQDs for phosphor-type light emitting diodes (LEDs). In contrast, a strong electroluminescence is potentially given by serving SiQDs as an emissive layer of current-driven LEDs with (Si-QLEDs) because the charged carriers are supplied from electrodes unlike absorption of light. Herein, we report that the external quantum efficiency (EQE) of Si-QLED was enhanced up to 12.2% by postproduction effect which induced by continuously applied voltage at 5 V for 9 h. The active layer consisted of SiQDs with a diameter of 2.0 nm. Observation of the cross-section of the multilayer QLEDs device revealed that the interparticle distance between adjacent SiQDs in the emissive layer is reduced to 0.95 nm from 1.54 nm by "post-electric-annealing". The shortened distance was effective in promoting charge injection into the emission layer, leading improvement of the EQE. [ABSTRACT FROM AUTHOR]

The catalytically active vanadium-containing system of γ-Al2O3 was studied using a wide range of physical and chemical methods, depending on the synthesis conditions. It is shown that the vanadium-containing system includes several complexes with different thermal stabilities and catalytic activities. Low-active complexes are destroyed with the formation of more active ones based on V2O5 oxide, as the temperature of heat treatment increases. It can be assumed that V2O5 oxide has the decisive role in its catalytic activity. It was concluded that the vanadium-containing catalytic system on aluminium oxide, in the studied temperature range, is thermally stable and shows high activity not only in the reduction of nitrogen oxides but also in the oxidation of hydrocarbons (even of the most difficult ones, such as oxidizable methane). These properties of the system make it quite promising in the field of application for the purification of the exhaust gases of motor transport and industrial enterprises with environmentally harmful components, as well as for understanding the mechanism of the action of the catalysts in these processes, which is very important for solving the problems of decarbonization and achieving carbon neutrality. [ABSTRACT FROM AUTHOR]

In this work, the optimal conditions for the electrodeposition of a CdSe film on n-Si were demonstrated. The structural and optical properties of the bare films and after annealing were studied. In particular, the crystallinity and photoluminescence of the samples were evaluated, and after annealing at 400 °C under a nitrogen atmosphere, a PL increase by almost an order of magnitude was observed. This paper opens the route towards the use of electrochemical deposition as a cost-effective and easy fabrication approach that can be used to integrate other interesting materials in the silicon-manufacturing processes for the realization of optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this article, red and green perovskite quantum dots are incorporated into the pixels of a flexible color-conversion layer assembly using microfluidics. The flexible color-conversion layer is then integrated with a blue micro-LED to realize a full-color display with a pixel pitch of 200 μm. Perovskite quantum dots feature a high quantum yield, a tunable wavelength, and high stability. The flexible color-conversion layer using perovskite quantum dots shows good luminous and display performance under different bending conditions; is easy to manufacture, economical, and applicable; and has important potential applications in the development of flexible micro-displays. [ABSTRACT FROM AUTHOR]

In this review, we discuss several fundamental processes taking place in semiconductor nanocrystals (quantum dots (QDs)) when their electron subsystem interacts with electromagnetic (EM) radiation. The physical phenomena of light emission and EM energy transfer from a QD exciton to other electronic systems such as neighbouring nanocrystals and polarisable 3D (semi-infinite dielectric or metal) and 2D (graphene) materials are considered. In particular, emission decay and FRET rates near a plane interface between two dielectrics or a dielectric and a metal are discussed and their dependence upon relevant parameters is demonstrated. The cases of direct (II–VI) and indirect (silicon) band gap semiconductors are compared. We cover the relevant non-radiative mechanisms such as the Auger process, electron capture on dangling bonds and interaction with phonons. Some further effects, such as multiple exciton generation, are also discussed. The emphasis is on explaining the underlying physics and illustrating it with calculated and experimental results in a comprehensive, tutorial manner. [ABSTRACT FROM AUTHOR]

The high-resolution Bitter technique for visualization (decoration) of the magnetic-flux structure in superconductors and magnets at low temperatures is presented. This method is based on the preparation of magnetic nanoparticles directly during a low-temperature experiment (in situ) by evaporating a magnetic material in the atmosphere of a buffer gas (helium) above the sample surface. An apparatus was constructed and a technique was proposed to stabilize the temperature of a sample during decoration with an accuracy of ±1 K within a wide temperature range. As an example, the results of observation of the magnetic-flux structure in single crystals of BSCCO(2212) high-temperature superconductor and EuFe2(As0.79P0.21)2 ferromagnetic superconductor at T ≤ 18 K are presented. [ABSTRACT FROM AUTHOR]

Actual state of affairs, main advantages and problems of Laser-Induced Breakdown Spectroscopy (LIBS) in analysis of industrial materials and environmental samples are discussed. Methods for LIBS sensitivity enhancement such as double-pulse ablation, a combination of LIBS with laser-induced fluorescence, the use of additional sources of excitation (spark) and confinement of plasma by magnetic field or shock wave are compared with respect to figures-of-merit. A set of LIBS approach to qualitative fast classification of materials, especially based on the correlation between parameters of laser plasma and sample properties, are discussed in details. Progress in environmental analysis of soils, sands etc. with the use of LIBS is demonstrated. Detection limits of the most elements in soils and aluminum alloys obtained until now are critically considered. [ABSTRACT FROM AUTHOR]

Semiexclusive measurements of the two-pion production reaction p( α, α′) pππ have been carried out at an energy of E α = 4.2 GeV at the Saturne-II (Saclay) accelerator with the SPES4- π installation. The two-pion production reaction was investigated by simultaneous registration of the scattered α particle and the secondary proton. The obtained results show that the two-pion decay of the P 11(1440) resonance excited in the target proton in this reaction proceeds predominantly with emission of two pions in the isospin I = 0, S-wave state. [ABSTRACT FROM AUTHOR]

The angular dependence of the tensor A yy and vector A y analyzing powers in the inelastic scattering of deuterons with a momentum of 9.0 GeV/ c on hydrogen and carbon has been measured. The range of measurements corresponds to the baryonic resonance excitation with masses of ∼2.2–2.6 GeV/ c 2. The A yy data, being in good agreement with the previous results, demonstrate an approximate t scaling up to −1.5 (GeV/ c)2. The large values of A y show a significant role of the spin-dependent part of the elementary amplitude of the NN → NN* reaction. The results of the experiment are compared with model predictions of the plane-wave impulse approximation. [ABSTRACT FROM AUTHOR]

The polarization of secondary protons from the ( p, 2 p) reaction induced by 1-GeV protons incident to a 4He nucleus was measured in a kinematically complete experiment. By using a two-arm magnetic spectrometer, two secondary protons from this reaction were recorded in coincidence at unequal scattering angles of Θ1 = 18°−24.21° and Θ2 = 53.22° over a broad range of the recoil-nucleus momentum K B between 0 and 150 MeV/ c. It was found that the measured polarization of either secondary proton is less than that observed in free elastic proton-proton scattering. The magnitude of this difference is determined by the mean binding energy of s-shell protons rather than by the effective nuclear density. The polarizations measured in inclusive quasielastic and elastic scattering of 1-GeV protons on 4He nuclei are presented for scattering angles in the range Θ1 = 18° − 24.21°. [ABSTRACT FROM AUTHOR]

The structural and tautomeric peculiarities, as well as physical/chemical properties of transition metal complexes with o -quinones are reviewed. Synthetic routes for obtaining these complexes starting from different sources (elemental metals, metal carbonyls, salts, and metal complexes) are described and tabulated. The free-radical properties of metal- o -quinone complexes are discussed. [ABSTRACT FROM AUTHOR]

The tensor A yy and vector A y analyzing powers in the inelastic scattering of deuterons with a momentum of 4.5 GeV/c on beryllium at an angle of ∼80 mr in the vicinity of baryonic resonances excitation have been measured. The A yy data being in good agreement with the previous results obtained at a zero angle demonstrate an approximate t scaling up to ∼ −0.9 (GeV/c)2. The results of the experiment are compared with the predictions of the multiple-scattering and ω-meson exchange models. [ABSTRACT FROM AUTHOR]

Preliminary results of the exclusive study of p(α, α′) X reaction at the α-particle momentum 7 GeV/c are presented. The missing mass spectra show fast change of the reaction mechanism in the range of the momenta of the scattered α-particle between 6.12 and 6.70 GeV/c. The mechanism of the Δ-resonance excitation in the projectile is confirmed. [ABSTRACT FROM AUTHOR]

Nanostructures are arising as novel biosensing platforms promising to surpass current performance in terms of sensitivity, selectivity, and affordability of standard approaches. However, for several nanosensors, the material and synthesis used make the industrial transfer of such technologies complex. Silicon nanowires (NWs) are compatible with Si-based flat architecture fabrication and arise as a hopeful solution to couple their interesting physical properties and surface-to-volume ratio to an easy commercial transfer. Among all the transduction methods, fluorescent probes and sensors emerge as some of the most used approaches thanks to their easy data interpretation, measure affordability, and real-time in situ analysis. In fluorescent sensors, Si NWs are employed as substrate and coupled with several fluorophores, NWs can be used as quenchers in stem-loop configuration, and have recently been used for direct fluorescent sensing. In this review, an overview on fluorescent sensors based on Si NWs is presented, analyzing the literature of the field and highlighting the advantages and drawbacks for each strategy. [ABSTRACT FROM AUTHOR]

A polarized proton beam from SATURNE II, the Saclay polarized targets with $^6$Li compounds, and an unpolarized $\mathrm{CH}_2$ target were used to measure spin-dependent observables for protons scattered on bound nucleons. The beam and target polarizations were oriented vertically. The analyzing power $A_{\mathrm{oono}}$ and the depolarization $D_{\mathrm{nono}}$ were determined at seven energies between 1.1 and 2.4 GeV. The spin correlation parameter $A_{\mathrm{oonn}}$ was measured at only 1.1 and 1.6 GeV. Measurements with the $\mathrm{CH}_2$ target at 1.1 GeV provided $A_{\mathrm{oono}}$ data for scattering of polarized protons on neutrons in carbon. The quasi-elastic observables are compared with previous elastic scattering measurements and at 1.1 GeV with predictions of phase shift analyses. [ABSTRACT FROM AUTHOR]

A polarized proton beam extracted from SATURNE II, the Saclay polarized target with $^6$Li compounds, and a $\mathrm{CH}_2$ target were used to measure elastic and quasi-elastic pp spin-dependent observables in the angular region $60^{\circ} < \theta_{\mathrm{CM}} < 105^{\circ}$. The beam and/or target polarizations were oriented vertically. Accurate pp data for the analyzing power $A_{\mathrm{oono}}$, spin-correlation parameter $A_{\mathrm{oonn}}$, and the polarization transfer $K_{\mathrm{onno}}$ were measured at 1.1 GeV. The observables $A_{\mathrm{oono}}$ and $K_{\mathrm{onno}}$ were determined at six other energies between 1.6 and 2.4 GeV. At 1.6 GeV, $A_{\mathrm{oonn}}$ was also obtained. The individual contributions from H, $^6$Li, and $^6$LiD were deduced. The $\mathrm{CH}_2$ target provided $A_{\mathrm{oono}}(\mathrm{pp})$ results on free hydrogen and on protons in carbon. The elastic and quasi-elastic observables are compared with existing data and with phase-shift analysis predictions. [ABSTRACT FROM AUTHOR]

The pp elastic scattering analyzing power was measured in small energy steps in the vicinity of the accelerator depolarizing resonance $\gamma G= 6 $ at 2.202 GeV. A vertically polarized proton beam was extracted from SATURNE II at energies above the resonance and passed through different copper degraders. The beam was focused on the beam line polarimeter CH $_2$ target. Its halo was removed by four powerful magnets. Measurements at degraded energies were complemented by data obtained with the directly extracted polarized beam outside the resonance region. Analyzing power results at fixed laboratory angles are compared with existing data in the region under discussion, with polynomial fits from 1.6 to 3.5 GeV, and with phase shift analysis predictions. [ABSTRACT FROM AUTHOR]

A polarized proton beam extracted from SATURNE II and the Saclay polarized proton target were used to measure the rescattering observables $K_{onno}$ and $D_{onon}$ at 26 energies from 1.94 to 2.80 GeV and at 0.80 GeV. The beam and target polarizations were oriented vertically and left-right as well as up-down asymmetries in the second scattering on carbon were measured. The present data, obtained in small energy steps, are practically constant as a function of energy at 90° CM, where $K_{onno} = D_{onon}$. These data will bring about important modification to phase shifts and stabilize the solutions. [ABSTRACT FROM AUTHOR]

The direct reconstruction of the pp elastic-scattering amplitudes and fixed-energy Saclay-Geneva phase shift analyses have been carried out at 1.80, 2.10, 2.40 and 2.70 GeV where complete sets of observables have recently been measured at SATURNE. They provide unique phase shift analysis solutions at 1.80, 2.10 and 2.40 GeV and two solutions at 2.70 GeV. Results of the direct amplitude reconstruction and the Saclay-Geneva phase shift analyses agree at all energies. Results are also compared to the Virginia Polytechnic Institute phase-shift predictions below 2.55 GeV and observed differences are discussed. [ABSTRACT FROM AUTHOR]

Results of the total cross section difference Δσ in a np transmission experiment at 1.19, 2.49 and 3.65 GeV incident neutron beam kinetic energies are presented. Measurements were performed at the Synchrophasotron of the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. Results were obtained with a polarized beam of free quasi-monochromatic neutrons passing through the new Dubna frozen spin proton target. The beam and target polarizations were oriented longitudinally. The present results were obtained at the highest energies of free polarized neutrons that can be reached at present. They extend the energy range of existing results from PSI, LAMPF and Saclay measured between 0.066 and 1.10 GeV. The new results are compared with Δσ ( pn) data determined as a difference between Δσ ( pd) and Δσ ( pp) ANL-ZGS measurements. The values of Δσ for the isospin state I=0 were deduced using known pp data. [ABSTRACT FROM AUTHOR]

A polarized proton beam extracted from SATURNE II and the Saclay polarized proton target were used to determine the spin correlation parameter Aoosk and the rescattering observables Kos″ so; Dos″ok, Nos″sn, and Nonsk at 1.80 and 2.10 GeV. The beam polarization was oriented perpendicular to the beam direction in the horizontal scattering plane and the target polarization was directed either along the vertical axis or longitudinally. Left-right and up-down asymmetries in the second scattering were measured. A check for the beam optimization with the beam and target polarizations oriented vertically provided other observables, of which results for Donon and Konno at 1.80, 1.85, 2.04, and 2.10 GeV are listed here. The new data at 2.10 GeV suggest a smooth energy dependence of spin triplet scattering amplitudes at fixed angles in the vicinity of this energy. [ABSTRACT FROM AUTHOR]

A better understanding of the compatibility of water-soluble semiconductor quantum dots (QDs) upon contact with the bloodstream is important for biological applications, including biomarkers working in the first therapeutic spectral window for deep tissue imaging. Herein, we investigated the conformational changes of blood plasma proteins during the interaction with near-infrared light-emitting nanoparticles, consisting of Pluronic F127 shells and cores comprised of assembled silicon QDs terminated with decane monolayers. Albumin and transferrin have high quenching constants and form a hard protein corona on the nanoparticle. In contrast, fibrinogen has low quenching constants and forms a soft protein corona. A circular dichroism (CD) spectrometric study investigates changes in the protein's secondary and tertiary structures with incremental changes in the nanoparticle concentrations. As expected, the addition of nanoparticles causes the denaturation of the plasma proteins. However, it is noteworthy that the conformational recovery phenomena are observed for fibrinogen and transferrin, suggesting that the nanoparticle does not influence the ordered structure of proteins in the bloodstream. In addition, we observed enabled cellular uptake (NIH3T3 Fibroblasts) and minimal cytotoxicity using different cell lines (HeLa, A549, and NIH3T3). This study offers a basis to design QDs without altering the biomacromolecule's original conformation with enabled cellular uptake with minimal cytotoxicity. [ABSTRACT FROM AUTHOR]

In this study, we investigate temperature-dependent photoluminescence (PL) in three samples of hydrogen-terminated silicon nanocrystals (ncSi-H) with different levels of surface oxidation.ncSi-H was oxidized by exposure to ambient air for 0 h, 24 h, or 48 h. The PL spectra as a function of temperature ranging between room temperature (~297 K) and 4 K are measured to elucidate the underlying physics of the PL spectra influenced by the surface oxidation of ncSi-H. There are striking differences in the evolution of PL spectra according to the surface oxidation level. The PL intensity increases as the temperature decreases. ForncSi-H with a smaller amount of oxide, the PL intensity is nearly saturated at 90 K. In contrast, the PL intensity decreases even below 90 K for the heavilyoxidized ncSi-H. For all the samples, full-width at half maxima (FWHM)decreases as the temperature decreases. The plots of the PL peak energy as a function of temperature can be reproduced with an equation where the average phonon energy and other parameters are calculated. [ABSTRACT FROM AUTHOR]

Various theoretical as well as empirical considerations about how to achieve lasing between the conduction and valence bands in indirect band gap semiconductors (germanium and silicon) are reviewed, starting from the dawn of the laser epoch in the beginning of the sixties. While in Ge the room-temperature lasing under electrical pumping has recently been achieved, in Si this objective remains still illusory. The necessity of applying a slightly different approach in Si as opposed to Ge is stressed. Recent advances in the field are discussed, based in particular on light-emitting Si quantum dots. [ABSTRACT FROM AUTHOR]

Here we report a quantum dot light emitting diode (QLED), in which a layer of colloidal silicon quantum dots (SiQDs) works as the optically active component, exhibiting a strong electroluminescence (EL) spectrum peaking at 620 nm. We could not see any fluctuation of the EL spectral peak, even in air, when the operation voltage varied in the range from 4 to 5 V because of the possible advantage of the inverted device structure. The pale-orange EL spectrum was as narrow as 95 nm. Interestingly, the EL spectrum was narrower than the corresponding photoluminescence (PL) spectrum. The EL emission was strong enough to be seen by the naked eye. The currently obtained brightness (∼4200 cd/m2), the 0.033% external quantum efficiency (EQE), and a turn-on voltage as low as 2.8 V show a sufficiently high performance when compared to other orange-light-emitting Si-QLEDs in the literature. We also observed a parasitic emission from the neighboring compositional layer (i.e., the zinc oxide layer), and its intensity increased with the driving voltage of the device. [ABSTRACT FROM AUTHOR]

The concept of synergistic effects has been widely applied in many scientific fields such as in biomedical science and material chemistry, and has further attracted interest in the fields of both synthesis and application of nanomaterials. In this paper, we report the synthesis of long-wavelength emitting silicon quantum dots based on a one-step hydrothermal route with catechol (CC) and sodium citrate (Na-citrate) as a reducing agent pair, and N-[3-(trimethoxysilyl)propyl]ethylenediamine (DAMO) as silicon source. By controlling the reaction time, yellow-emitting silicon quantum dots and green-emitting silicon quantum dots were synthesized with quantum yields (QYs) of 29.4% and 38.3% respectively. The as-prepared silicon quantum dots were characterized by fluorescence (PL) spectrum, UV–visible spectrum, high resolution transmission electron microscope (HRTEM), Fourier transform infrared (FT-IR) spectrometry energy dispersive spectroscopy (EDS), and Zeta potential. With the aid of these methods, this paper further discussed how the optical performance and surface characteristics of the prepared quantum dots (QDs) influence the fluorescence mechanism. Meanwhile, the cell toxicity of the silicon quantum dots was tested by the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium (MTT) bromide method, and its potential as a fluorescence ink explored. The silicon quantum dots exhibit a red-shift phenomenon in their fluorescence peak due to the participation of the carbonyl group during the synthesis. The high-efficiency and stable photoluminescence of the long-wavelength emitting silicon quantum dots prepared through a synergistic effect is of great value in their future application as novel optical materials in bioimaging, LED, and materials detection. [ABSTRACT FROM AUTHOR]

New data on the spin-dependent np observables measured with quasi-monochromatic polarized neutron beam in the energy region from 1.2 to 3.7 GeV are presented. Further measurements of np scattering observables using the JINR LHE polarization facility (longitudinal and transverse polarized neutron beams and a polarized proton target) are discussed. The aim of these studies is to determine the imaginary and real parts of the forward scattering amplitudes for np and for isospin I=0 systems above 1.1 GeV. [ABSTRACT FROM AUTHOR]