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Invariance under the charge, parity, time-reversal (CPT) transformation (1) is one of the fundamental symmetries of the standard model of particle physics. This CPT invariance implies that the fundamental properties of antiparticles and their matter-conjugates are identical, apart from signs. There is a deep link between CPT invariance and Lorentz symmetry--that is, the laws of nature seem to be invariant under the symmetry transformation of spacetime--although it is model dependent (2). A number of high-precision CPT and Lorentz invariance tests--using a co-magnetometer, a torsion pendulum and a maser, among others--have been performed (3), but only a few direct high-precision CPT tests that compare the fundamental properties of matter and antimatter are available (4-8). Here we report high-precision cyclotron frequency comparisons of a single antiproton and a negatively charged hydrogen ion ([H.sup.-]) carried out in a Penning trap system. From 13,000 frequency measurements we compare the charge-to-mass ratio for the antiproton [(q/m).sub.[bar.p]] to that for the proton [(q/m).sub.p] and obtain [(q/m).sub.[bar.p]]/[(q/m).sub.p] - 1 = 1(69) x [10.sup.-12]. The measurements were performed at cyclotron frequencies of 29.6 megahertz, so our result shows that the CPT theorem holds at the atto-electronvolt scale. Our precision of 69 parts per trillion exceeds the energy resolution of previous antiproton-to-proton mass comparisons (7,9) as well as the respective figure of merit of the standard model extension (10) by a factor of four. In addition, we give a limit on sidereal variations in the measured ratio of < 720 parts per trillion. By following the arguments of ref. 11, our result can be interpreted as a stringent test of the weak equivalence principle of general relativity using baryonic antimatter, anti it sets a new limit on the gravitational anomaly parameter of [absolute value of ([α.sub.g] - 1)] < 8.7 x [10.sup.-7]., The standard model is the theory that describes particles and their fundamental interactions, although without taking into account gravitation. However, this model is known to be incomplete, which has inspired [...]

Initially our method of the decomposition of charge state distributions of biopolymer ions was designed to estimate the probabilities of the retention of charges by biopolymer ionogenic groups without distinction of different charge carriers (proton, alkali metal ions, or other ions). The analysis of mass spectra of several peptides and proteins produced by electrospray ionization carried out on this basis made possible some conclusions about their ion structure and behavior inside the ion source. A generalization of the method for the case of multidimensional charge state distributions corresponding to the retention of various charge carriers by ions of biomolecules is described. Hopefully, this will make possible gaining more substantial information concerning the structure and behavior of biomolecule ions in solutions and under electrospray conditions, which can be important for various biological applications. Keywords: electrospray, biomolecules, multiply charged ions, charge state distribution, decomposition of distributions, ionogenic groups, probabilities of charge retention DOI: 10.1134/S1061934814130073, INTRODUCTION Electrospray ionization (ESI) [1, 2] is one of the most important methods of mild ionization and widely used for structural and conformational studies of biomolecules. The mass spectra of [...]

A study was conducted to examine the program and retention transients of silicon nitride-based (SONOS/TANOS) nonvolatile memories using a new characterization technique and an improved model for charge injection and transport through ONO gate stacks. Results reveal that the carrier transport in the SiN layer affects the spatial distribution of the trapped charge and various aspects of program and retention transients.

An analytical model is used for organic thin-film transistors that has accounted for the affect of trap states on the current voltage characteristics. The subthreshold regime has reacted to the presence of traps and hence it is used for extracting approximate trap parameters from experimental transistor data.

A modeling technique that uses charge transport equations to calculate channel current in organic field effect transistors (OFETs) by numerical solution in the SPICE simulation program is reported. The modeling technique is a bridge between physical models of charge transport and a SPICE model useful in circuit simulation without requiring a closed-form drain-current equation.

The electrical performance and programming/erasing (P/E) mechanism of dual charge storage layer (DCSL) and Flash memories using a [Si.sub.3][N.sub.4] (NROM)-type multilevel-cells (MLCs) are examined. DCSL MLCs have shown negligible threshold-voltage ([V.sub.th])-level offsets that are maintained throughout the [10.sup.5] P/E cycles, which has shown improved endurance reliability compared to NROM-type MLCs.

The origin of the surface conductivity of H-terminated diamond films immersed in aqueous electrolyte is examined. Charge transfer across the diamond interface has not governed the surface conductivity in aqueous electrolyte when a gate electrode has controlled the diamond/electrolyte interfacial potential, but it has allowed the capacitive charging of the surface.

The triplet state of dipole moments of aminobenzonitriles is recalculated on the basis of newly measured intersystem crossing yields. The dipole moment of 4-(dimethylamino)benzonitrile (DMABN) in the triplet state is not found to be a reliable indication of the extent of charge transfer compared to other states.

Femtosecond vibrational spectroscopy is used for studying the mechanism of proton transfer (PT) between the photacid (8-hydroxy-1,3,6-pyrenetrisulfonic acid (HPTS)) and the base acetate in aqueous solution. It is shown that an activated solvent configuration is required for long-range PT to facilitate the charge transfer.

A junction termination extension avalanche photodiode (APD) is evaluated for x-ray detection. Findings reveal that the structure posses the potential to make very low-noise detectors with high reliability after optimization of the implanted charge.

A CASPT2 study of the electronic spectrum of hexacyanoosmate(III) is employed to determine the value of the ligand field splitting parameter of the complex. The observed spectrum is shown to be a result of the ligand-to-metal charge-transfer (LMCT) excitations.

Resorc[4]arene octamethyl ethers have formed very stable 1:1 nitrosonoim complexes when they are treated with NOB[F.sub.4] salt in chloroform. The presence of ester carbonyl groups in these ethers have driven the N[O.sup.} cation outside the resorcarene and resorc[4]arene has showed a spectral pattern pointing out the involvement of the ester moieties in the N[O.sup.} entrapping, beside the formation of charge-transfer interactions.

Charge-transfer quenching of the singlet excited states of cyanoaromatic electron acceptors by pyridine is characterized by using a driving force dependence reactions. Evidence is provided for bonded exciplex intermediate from studies of steric and Coulombic effects on the quenching rate constants, which have shown a curve crossing between the ground state and the low-energy bonded exciplex state.

The design and synthesis of a novel series of monodisperse, multi-dipolar zigzag oligoaryleneethynylenes DA(n) and D-Ar-A(n) bearing electron-donating dibenzothiophene and electron-accepting dibenzothiophene dioxide as arenes, with up to six charge-transfer units are described by palladium-catalyzed Sonogashira coupling reactions. The results have shown that the two-photon absorption (TPA) properties of the zigzag oligoarylenethynylenes can be tuned by means of modifying the central aryleneethynylene units and increasing the number of dipolar units.

A study was conducted to determine how branching of quadrupolar chromophores can lead to different consequences as compared to branching of dipolar chromophores. Theoretical study reveals that a symmetrical intramolecular charge transfer from the terminal donating groups to the middle of the molecule takes place in all quadrupolar chromophores upon photoexcitation.

An analysis of the charge-transfer absorption from a transition-metal-cyanide complex to a Ti[o.sub.2] nanoparticle is done. It is suggested that the transition includes the transfer of an electron to a conduction-band state which is dominated by contributions from the Ti(IV) center coordinated to the metal-cyanide complexes and transition does not lead to the direct transfer of an electron into a state delocalized over the entire particle.

The rate constants for radiative decay, radiationless decay, and intersystem crossing for a range of excited states formed by reaction of cyanoanthracene acceptors with alkylbenzenes as donors in different solvents of moderate to low polarity are presented. The basic parameters that govern the rate constants for radiationless decay in excited states with intermediate charge-transfer character are described.

The electrochemical and spectroelectrochemical analysis is done to determine the influence of anions on the IVCT processes in the mixed-valence dinuclear ruthenium and osmium complexes. Results showed significant differences in the two techniques in the order and extent of effects induced by a number of inorganic anions.

Ultrafast transient absorption spectroscopy was used to investigate the solvation dynamics of newly created sodium atoms that are formed following the charge transfer to solvent (CTTS) ejection of an electron from tetrahydrofuran (THF). It was found that the neutral sodium species created following CTTS excitation of sodium initially absorbs near 590nm which the position of the gas-phase sodium D-line indicating that it weakly interacts with the surrounding solvent.

The newly designed [2]catenane that incorporates hydroquinone (HQ) and a sterically bulky tetrathiafulvalena (TTF) into a bismacrocyle is found to probe two classes of alongside charge-transfer (CT) interactions. The profiles of the CT bands are found to change with the ratio of the cis- to trans-TTF isomers, giving different overlap of the employed compounds.

The investigation of the organic light emitting diode (OLED) emitter Ir[(btp).sub.2](acac) in a C[H.sub.2][Cl.sub.2] matrix by highly resolving emission and excitation spectroscopy showed that the emitting state is a ligand centered state with significant metal-to-ligand charge transfer (MLCT) perturbation which is sensitive to the environment.

Gas breakdown caused by triboelectricity during friction between two insulators was observed in measuring two-dimensional spatial distributions of luminescence from gas discharge plasma. The insulators were chosen among diamond, quartz, sapphire, MgO single crystal, and quartz glass. The discharge between identical materials was also observed. The patterns of the gas discharge luminescence had a shape of a ring for all frictions between insulators. By using a gold-coated diamond pin for friction with a quartz disk, the discharge pattern differed from the ring pattern. In the case of insulator pin, electric field induced by a localized charge at the off-track area near the tip of the pin during friction accounts for formation of the ring shape of the gas discharge. The gold coating makes it possible to monitor an amount of charge transferred from the quartz surface during friction. The negative charge density at the frictional track on the quartz disk is calculated to be -2.2x[10.sup.4] C/[m.sup.2], which leads the gas discharge in a micro-gap near the contact between the diamond pin and the quartz disk. Index Terms--Triboelectricity, Insulators, Charge transfer, Gas discharges, Electrostatic measurements, and Electrostatic discharges.

A design strategy of a new ratiometric cadmium fluorescent sensor is described for enhancing the discrimination of cadmium from zinc by undergoing two different internal charge transfer (ICT) methods and the high selectivity of sensor to cadmium over some metals. The distinct role of the 2-picolyl group in the ratiometric cadmium fluorescent sensor- cadmium complexation is described using structure derivation and a series of NMR analysis.

The (p-tolylsulfonyl)methyl isocyanide (TosMIC) method as a critical coupling reaction was used to carry out synthesis of a series of three- to six-layered [3.3]metacyclophanes ([3.3]MCPs). The charge-transfer (CT) bands of the multilayered [3.3]MCP-di- and tetraones, the anti-[3.3]MCPs with one anti-[3.3]MCP-dione moiety shows the almost comparable magnitude of the interaction with the two- and three- layered [3.3]MCPs respectively and tetraones of the three and four-layered MCPs do not show CT interactions except for the six-layered MCP.

The synthesis, characterization and photoinduced electron properties of three poly(bipyridyl) hexanucelar complexes consisting of one [Mn.sub.2.sup.III,IV][([mu]-O).sub.2][(dmpy).sub.4]-type subunit covalently linked to four photoactive [Ru.sup.II][[(dmpy).sub.3] moieties are described. It is shown that in these complexes a partial quenching of the metal-to-ligand charge transfer (MLCT) excited state of the [Ru.sup.II] centers by the [Mn.sub.2.sup.III,IV] unit occurs and it is possible to induce the oxidation of a [Mn.sub.2][([mu]-O).sub.2] core.

The kinetics of the charge-transfer systems are formulated in a microstate form to understand the simulations of the electron transfer between the tetraheme subunit and the special pair of the photosynthetic reaction of the proteins. The analysis reveals that the electron-transfer rate constants can be easily obtained by using the combination of the various electrostatic calculations with the existing empirical rate law.

Organic-inorganic multilayer structures of the silicon/poly (diphylenepthalide)/Cu type were prepared and their electrical properties were studied. The obtained results were treated within different models of charge transport and it was concluded that the dominant charge injection mechanism at higher temperatures is the thermionic emission.

Organic-inorganic multilayer structures of the silicon/poly (diphylenepthalide)/Cu type were prepared and their electrical properties were studied. The obtained results were treated within different models of charge transport and it was concluded that the dominant charge injection mechanism at higher temperatures is the thermionic emission.

The nanoporous Ti[O.sub.2] network sensitized by ZnS nanospheres is produced and described as an idealized scheme to facilitate interfacial charge transfer effects. The findings suggest that when a large band gap material is restricted in a confined geometry of lower energy band gap then the surface states are mainly responsible in the charge transport phenomena.

A semiclassical model is proposed for interfacial charge-transfer absorption (IFCTA) to metals and semiconductors that consider the fact that, unlike molecules, both semiconductors and metals possess closely spaced occupied electronic levels and closely spaced unoccupied levels so that a common framework is appropriate for describing their interfacial charge-transfer processes. It is concluded that the photoinduced charge-transfer processes involve a small number of atoms per acceptor site on the surface of the nanoparticle.

The dependence of the electron transport and recombination dynamics on the internal surface area of mesoporous nanocrystalline Ti[O.sub.2] films in dye-sensitized solar cells is examined. The results have confirmed that photoinjected electrons recombine with redox species in the electrolyte through surface states rather than from the Ti[O.sub.2] conduction band.

Two newly synthesized pyrenylcyclam dendrons have displayed unique emissive blue shifts centered at 450 nm upon adding copper triflate, which are attributed to intramolecular excimer emission. Metal complexation and intramolecular photoinduced electron transfer within the dendritic 1:1 cyclam/metal complex have played vital roles in the photophysical properties in metal/dendrimer complexes.

The synthesis, spectroscopic and electrochemical data of donor-acceptor-donor tetrazines containing ferrocene moieties and phenyl unit as a [pi]-bridge are presented. The ultraviolet (UV)-vis spectroscopic and cyclic voltamperometric results have indicated sizable intramolecular charge transfer interactions in the ground state when the ferrocene is directly bound to the tetrazine and have shown reduction of the electron-donor strength of ferrocene moieties when there is a phenyl linkage.

The electronic structure and charge transfer characteristics of two structural isomers of donor-acceptor substituted sesquifulvalene are studied by using a sufficiently high level of ab initio quantum mechanical methods. Since the chosen molecules are polar and only the dominant solute-solvent electrostatic interaction is considered, the variation of their rotational energy barriers and transition energies in solution can be interpreted and distinguished from each other in terms of the polarity difference between the ground and excited states.

Photochemical properties trans-3,3',5,5'-tetramethoxystilbene (TMST) is studied in various polar solvents. The results have indicated that the excited singlet state of trans-TMST has a charge-transfer (CT) character.

First principles methods are used to investigate the adsorption of N[O.sub.2] molecules on a series of zigzag (n,0) single-walled carbon nanotubes (SWNTs) (n = 6-12). The results have indicated that the tube diameter and the concentration of N[O.sub.2] gas determine the interactions between N[O.sub.2] and tube and the SWNT possesses the radical characteristic, which facilitates the further characterization of the tube wall.

The friction and triboelectrification between both similar and dissimilar molecularly smooth hexadecanethiol-coated metal surfaces on mica substrates were simultaneously measured using a modified surface forces apparatus. Results indicate that frictional dissipation induces electron-hole formation and charge transfer between two shearing surfaces due to molecular-level roughness and defects and local dielectric constant changes, giving rise to the observed tribocurrents.

A method for estimating the positions of charge transfer (CT) bands in [Eu.sup.3+]-doped complex crystals is reported. The relationship between the experimental CT energies and calculated environmental factors is established by an empirical formula.

The development, operation, and characterization of charge-coupled devices (CCDs) that feature an electrode structure that allows the transfer of charge both horizontally and vertically through the image area is described. The ability of both two dimensional transfer CCDs (2DT CCD) transfer electrode schemes to successfully transfer charge in both horizontal and vertical directions in the image section of the devices is proven, opening up potential new applications for 2DT CCD use.