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The ongoing spread of drug-resistant bacterial infections poses a significant threat to public health, and early diagnosis and targeted treatment are the keys to successful treatment. Traditional bacterial culture and drug susceptibility testing is time-consuming and insensitive, and cannot meet the needs of clinical diagnosis and treatment, so molecular detection technologies, such as metagenomics next-generation sequencing, have become a new research direction. This article reviewed recent advances in high-throughput sequencing for the diagnosis and treatment of drug resistance in Gram-negative bacteria.耐药细菌感染的不断蔓延对公共卫生安全构成重要威胁，早期诊断和目标治疗是治疗成功的关键。传统细菌培养及药物敏感性检测耗时长、敏感性不高，无法满足临床诊治需求，高通量测序等分子检测技术成为新的发展方向。本文对近年来有关高通量测序在革兰阴性菌耐药诊治中的进展做一综述。.

Mass-separated ${^{187}\mathrm{Ta}}_{114}$ in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal $\ensuremath{\gamma}$ rays revealed a ${T}_{1/2}=7.3\ifmmode\pm\else\textpm\fi{}0.9\text{ }\text{ }\mathrm{s}$ isomer at $1778\ifmmode\pm\else\textpm\fi{}1\text{ }\text{ }\mathrm{keV}$, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer-decay reduced $E2$ hindrance factor ${f}_{\ensuremath{\nu}}=27\ifmmode\pm\else\textpm\fi{}1$ supports the interpretation that axial symmetry is approximately conserved.

Uric acid is considered a biomarker for cardiovascular risk. Only a few studies have investigated the effect of aspirin on serum uric acid (SUA) levels with contradictory results. The present study evaluated the effect of aspirin on SUA levels in Chinese individuals over 60 years of age.Subjects over 60 with coronary artery disease or multiple cardiovascular risk factors were enrolled in a multicentre randomized clinical trial. Eligible subjects were randomized to receive 50 mg or 100 mg aspirin daily. Levels of arachidonic acid-induced platelet aggregation performed by light transmission aggregometry (LTA-AA) and SUA were measured at randomization and two weeks thereafter. In this subanalysis, subjects without aspirin use prior to enrolment were chosen.A total of 446 subjects were analysed, of which 151 subjects took 50 mg aspirin, and 295 took 100 mg aspirin. Hyperuricaemia was present in 23.3% (104/446) of subjects at baseline. LTA-AA levels were significantly reduced in subjects after taking aspirin for two weeks (both 50 mg and 100 mg, p0.001). SUA levels were decreased after aspirin administration (311 μmol/L vs. 302 μmol/L, p0.001). Further analysis showed SUA levels were unchanged in normouricaemic subjects (284 μmol/L vs. 280 μmol/L, p0.05), while slightly decreased in hyperuricaemic subjects (429 μmol/L vs. 392 μmol/L, p0.001).Our study showed that both 50 mg and 100 mg aspirin significantly inhibited platelet aggregation. Aspirin treatment for two weeks showed no hyperuricaemic effect in people over 60. SUA levels were unchanged after taking aspirin in normouricaemic subjects but decreased in hyperuricaemic subjects. This trial was registered at www. chictr.org.cn as ChiCTR1800018517.

A series of multi-walled carbon nanotube (MWCNT)/epoxy composite films with a thickness of ~700 µm is prepared by a sequential process of premixing, post dispersing, film casting, and thermal curing. The effects of the physical shear dispersion on the properties of conductive polymer composites as the electric heating element are investigated. The scanning electron microscope (SEM) images show that highly efficient conductive networks form with shear dispersions of MWCNTs in the polymer matrix. The electrical resistivity decreases sharply from ~1015 Ω·cm for the neat epoxy resin to ~102 Ω·cm for the composite film with 2.0 wt% MWCNTs in accordance with the percolation behaviour, and a low percolation threshold of ~0.018 wt% is fitted. The electric heating behaviour of the composite film is observed at a low MWCNT content of 0.05 wt% due to the high electrical conductivity. For the composite film with 2.0 wt% MWCNTs, an equilibrium temperature of 115 °C is reached at an applied voltage of 40 V within 30 s. The excellent electric heating behaviour, including the rapid temperature response, electric heating efficiency, and operational stability, is primarily related to the conductive two-dimensional networks consisting of MWCNTs and the thermodynamically stable polymer matrix.

Sadomasochism is the sexual interest, psychosexual deviance or sexual crimes that are sexually aroused by suffering or causing others to suffer. This study summarizes the concept, assessment and diagnosis, categories and symptoms, psychological and biological mechanisms, judicial disposition and clinical intervention strategies of sadomasochism from the perspectives of clinical medicine, law, criminology and psychology, suggests that further research should take local people with sadomasochism preference and local patients as research objects, pay attention to different types of sadomasochists, conduct bottom-up research, explore the core elements and manifestations of sadomasochism, and accurately define and classify sadomasochism, construct an effective scale, a erectile measurement sexual stimulation system and a diagnostic criteria; discuss evaluation methods combined with crime scene data; discuss the validity of masochists' consent combined with diagnosis; establish targeted criminal correction programs and a treatment and rehabilitation system to provide reference for the improvement of medical, judicial and mental health services.性施（受）虐的研究现状与局限.性施（受）虐是指通过遭受痛苦或使他人痛苦来获得性唤起的性偏好、性心理障碍或性犯罪行为。本文综述了从临床医学、法学、犯罪学、心理学等视角对性施（受）虐的概念、评估与诊断、分类与症状表现、心理学与生物学机制、司法处置与临床干预策略的研究，提出进一步的研究应以本土性施（受）虐偏好者、患者为研究对象，关注不同类型的性施（受）虐群体，开展自下而上的研究，探讨性虐行为的核心要素和表现形式，准确定义和分类性施（受）虐，构建有效的量表、勃起测量性刺激体系和诊断标准，探讨结合犯罪现场信息的评估方法，探讨结合诊断讨论性受虐者同意的有效性，建立针对性的罪犯矫治项目和治疗康复体系，为医疗、司法、心理健康服务工作的改善提供参考。.司法精神病学；性虐待；施虐癖；受虐癖；性犯罪；综述.

Collective rotational bands were observed for the first time in neutron-rich odd–odd [Formula: see text]La by means of [Formula: see text]-[Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] coincidence measurements of prompt fission [Formula: see text] rays from [Formula: see text]Cf using multi-detector array Gammasphere. Similarity between the yrast band of [Formula: see text]La and those of neighboring [Formula: see text]La, [Formula: see text]Ce was found and interpreted as quasiparticle excitations. PES calculations suggested triaxial deformation for the ground state of 142La. Considerable triaxial and near zero octupole deformations were deduced for the yrast band of [Formula: see text]La by the TRS model calculations. The band-crossing observed in the yrast band of [Formula: see text]La was interpreted to be caused by alignment of the (h[Formula: see text])2 proton pair, and the crossing frequency was best reproduced by the TRS calculations taking into account triaxial deformations. In contrast to the interpretations for the band crossing of [Formula: see text]La, alignments of the (i[Formula: see text])2 neutron pair were found to be responsible for the band-crossing of the yrast band in the neighboring even-N [Formula: see text]La, and triaxial degree of freedom was found to play a more significant role than octupole deformations in the nucleus, although its [Formula: see text] values deduced are large.

At present, the application of the Internet of Things (IoT) is typically centered on a gateway device controlled/manipulated by the user with a mobile App. The peripheral (sensor) devices send the surrounding information (such as temperature, humidity, etc.) to the gateway, which processes and uploads the information to the cloud. When developing the software of an IoT device (a gateway device, App, or peripheral device), it is important to make sure that the device is compatible with the other devices. In particular, before releasing a new version, the tester needs to conduct a thorough testing to ensure that the new version is compatible to all versions of the other devices. This is costly and very time consuming. To overcome this problem, this paper proposes a compatibility testing tool called ICAT (Internet of things CompAtibility Testing tool). ICAT allows a tester to select a target environment, a particular version combination of the IoT devices, and performs compatibility testing for the devices. A test report is offered when the testing is completed. Our experimental results show that using ICAT can improve test coverage and reduce test cost.

High-spin-level schemes of $^{118,119}\mathrm{Ag}$ are established for the first time by analyzing the high statistics $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ and $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ coincidence data from the spontaneous fission of $^{252}\mathrm{Cf}$ at Gammasphere. Two bands with 12 new levels in $^{118}\mathrm{Ag}$ and three bands with 14 new levels in $^{119}\mathrm{Ag}$ have been identified. A total Routhian surface calculation and projected shell model calculation have been performed to understand the behavior of these two nuclei. The calculations indicate oblate shape in $^{118,119}\mathrm{Ag}$.

Exact analysis of displacements and stresses in 2-D orthotopic laminates under extension is conducted. On the basis of the Hamiltonian state space approach and the transfer matrix method, a complete solution, in the context of generalized strain, which exactly satisfies the state space equation, the traction-free BC on the top and bottom surfaces of the rectangular section, the interfacial continuity conditions in multi-layered laminates, and the end conditions on free edges, is obtained by combing the eigensolutions and the particular solution. Evaluating of the stresses in the boundary layer for verification shows that the stress decay in laminates under uniform extension may be slow and the edge effects may be pronounced.

The collective rotations of the configuration in neutron-rich Mo, Ru and Pd isotopes were systematically investigated by the configuration-constrained cranking shell model based on the Skyrme Hartree-Fock method with pairing treated by shell-model diagonalization. The calculations efficiently reproduce the experimental moments of inertia of both the ground-state and side bands. Rotational bands built on two-particle configurations have been the subject of intense study. Possible configurations were assigned to the observed bands in 102-106Mo, 108-112Ru and 112-114Pd. We predict the existence of the bands in 108,110Mo. These results provide deep insights into the structure of neutron-rich nuclei, and provide useful information for future experiments.

Mass spectrum of 13 D 1 meson state is phenomenologically deduced in the framework of non-relativistic constituent quark model, Regge phenomenology and meson-meson mass mixing matrix. Results can be used to search for the members of 13 D 1 meson state and to distinguish newly discovered states in experiments.

High-spin states in $^{155}\mathrm{Yb}$ have been studied via the $^{144}\mathrm{Sm}(^{16}\mathrm{O},5n)^{155}\mathrm{Yb}$ reaction at a beam energy of 118 MeV. One negative-parity and one positive-parity cascade built on the $\ensuremath{\nu}{f}_{7/2}$ and $\ensuremath{\nu}{i}_{13/2}$ states, respectively, are established for the first time. The structures observed in $^{155}\mathrm{Yb}$ are compared with those in the neighboring $N=85$ isotones and with semiempirical shell-model (SESM) calculations. According to adiabatic and configuration-fixed constrained triaxial covariant density functional theory (CDFT) calculations, a coexistence of prolate and oblate shapes is predicted to exist in $^{155}\mathrm{Yb}$.

High-spin states of $^{123}\mathrm{Ba}$ have been studied via the $^{108}\mathrm{Cd}(^{19}\mathrm{F},3np)^{123}\mathrm{Ba}$ fusion-evaporation reaction at a beam energy of 90 MeV. Several $E1$ transitions linking the positive-parity $\ensuremath{\nu}({d}_{5/2}+{g}_{7/2})$ band and negative-parity $\ensuremath{\nu}{h}_{11/2}$ band are observed in $^{123}\mathrm{Ba}$ for the first time. Evidence for the existence of octupole correlations in $^{123}\mathrm{Ba}$ is presented based on the systematic comparisons of the $B(E1)/B(E2)$ branching ratios and the energy displacements in odd-$A$ Ba isotopes. The characteristics of octupole correlation in the odd-$A\phantom{\rule{0.28em}{0ex}}^{123,125}\mathrm{Ba}$ are explained by the state-of-the-art multidimensionally-constrained relativistic mean-field model and cluster model based on the dinuclear system concept.

Pairing-deformation-frequency self-consistent cranking Woods-Saxon model is employed to investigate the triaxiality in the ground states of the neutron-rich even-even Mo, Ru isotopes. Deformation evolutions and transition probabilities have been studied, giving the triaxial shapes in their ground states. The kinematic moments of inertia have been calculated to illustrate the gradually rigid deformation. To understand the origin of the asymmetry shape in this region, we analyze the evolution of single-particle orbits with changing $\gamma$ deformation. The present calculations reveal the importance of the triaxial deformation in describing not only static property, but also rotational behaviors in this mass region, providing significant probes into the shell structure around.

Two-dimensional electrophoresis (2-DE) was used to analyze proteins isolated from different developmental stages of longan (Dimocarpus longan Lour.) zygotic embryos. Eighteen differential and house-keeping proteins were chosen to analyze by MALDI-TOF/MS or MALDI-TOF-TOF/MS. Twelve proteins were identified by searching Matrix Science database. Among six differential proteins, protein L2 was identified as FH protein interacting protein (FIP2). Protein L6 was identified as Pre-mRNA cleavage complex ii protein clp1-related which was related to pre-mRNA splicing. Protein L8 was identified as flavanone 3-hydroxylase (F3H). Protein L3 was identified a homologous conserved sequence with Ribosomal_L7Ae mRNA sequence, and protein L1 is Queuine tRNA-ribosyltransferase (TGT), which was detected first time in plant. Among four house-keeping proteins, Protein L11 (BCAT) was identified enzyme related to sugar metabolism. Protein L18 was identified as heat shock proteins (HSPs). The function of these proteins was also discussed. But the function of protein L12 (3-hydroxyisobutyryl-coenzyme A hydrolase homology) and L15 (At1g14310) still remain unknown.

Background: Nuclear collective rotations have been successfully described by the cranking Hartree-Fock-Bogoliubov (HFB) model. However, for rotational sidebands which are built on intrinsic excited configurations, it may not be easy to find converged cranking HFB solutions. The nonconservation of the particle number in the BCS pairing is another shortcoming. To improve the pairing treatment, a particle-number-conserving (PNC) pairing method was suggested. But the existing PNC calculations were performed within a phenomenological one-body potential (e.g., Nilsson or Woods-Saxon) in which one has to deal the double-counting problem.Purpose: The present work aims at an improved description of nuclear rotations, particularly for the rotations of excited configurations, i.e., sidebands.Methods: We developed a configuration-constrained cranking Skyrme Hartree-Fock (SHF) calculation with the pairing correlation treated by the PNC method. The PNC pairing takes the philosophy of the shell model which diagonalizes the Hamiltonian in a truncated model space. The cranked deformed SHF basis provides a small but efficient model space for the PNC diagonalization.Results: We have applied the present method to the calculations of collective rotations of hafnium isotopes for both ground-state bands and sidebands, reproducing well experimental observations. The first up-bendings observed in the yrast bands of the hafnium isotopes are reproduced, and the second up-bendings are predicted. Calculations for rotational bands built on broken-pair excited configurations agree well with experimental data. The band-mixing between two ${K}^{\ensuremath{\pi}}={6}^{+}$ bands observed in $^{176}\mathrm{Hf}$ and the $K$ purity of the $^{178}\mathrm{Hf}$ rotational state built on the famous 31 yr ${K}^{\ensuremath{\pi}}={16}^{+}$ isomer are discussed.Conclusions: The developed configuration-constrained cranking calculation has been proved to be a powerful tool to describe both the yrast bands and sidebands of deformed nuclei. The analyses of rotational moments of inertia help to understand the structures of nuclei, including rotational alignments, configurations, and competitions between collective and single-particle excitations.

The spectroscopy of $^{73}\text{Ge}$ has been investigated via the $^{70}\text{Zn}(^{7}\text{Li},3np)^{73}\text{Ge}$ fusion-evaporation reaction. A previously known band built on the $\ensuremath{\nu}({f}_{5/2})$ orbital is extended up to higher-spin states and a new rotational band built on the $\ensuremath{\nu}({g}_{9/2})$ orbital is established. The observed band crossing and shape evolution induced by the alignment in $^{73}\text{Ge}$ are studied in comparison with the similar structures in the neighboring $N=41$ isotones and the cranked Woods--Saxon--Strutinsky calculations by means of total-Routhian-surface (TRS) methods. The inversion of the order of the ${g}_{9/2}$ neutron and the ${g}_{9/2}$ proton crossing frequency observed in the negative-parity $\ensuremath{\nu}({f}_{5/2})$ bands between $^{73}\text{Ge}$ and $^{75}\text{Se}$, $^{77}\text{Kr}$ can be ascribed to their different triaxial deformations. At higher spins, both the $\ensuremath{\nu}({f}_{5/2})$ and $\ensuremath{\nu}({g}_{9/2})$ bands in $^{73}\text{Ge}$ undergo a shape evolution with sizable alignments occurring. The characters of large signature splitting in $\ensuremath{\nu}({g}_{9/2})$ band of $^{73}\text{Ge}$ are discussed.

The spectroscopy of $^{76}\mathrm{Se}$ has been studied using the $^{70}\mathrm{Zn}(^{12}\mathrm{C}, \ensuremath{\alpha}2{\mathrm{n})}^{76}\mathrm{Se}$ fusion evaporation reaction. The yrast band of $^{76}\mathrm{Se}$ has been extended to substantially higher spin, allowing observation of the second band crossing. The much-delayed ${g}_{9/2}$ proton-pair alignment is discussed in terms of the cranked shell model and most likely is caused by a shape transition from prolate to oblate along the yrast line occurring in $^{76}\mathrm{Se}$. Based on the systematic investigation of the band crossings associated with the ${g}_{9/2}$ quasiparticle alignments and their relationships with the shape evolutions in the even-$A$ Se and Kr isotopes, a comprehensive picture of shape evolution along with spin and isospin in these nuclei is obtained.

With the superconducting cuprates in mind, a set of unitary transformations was used to decouple electrons and phonons in the strong-coupling limit. While phonons remain almost unrenormalised, electrons are transformed into itinerent singlet and triplet bipolarons and thermally excited polarons. The triplet/singlet exchange energy and the binding energy of the bipolarons are thought to account for the spin and charge pseudogaps in the cuprates, respectively. We calculated the Hall Lorenz number of the system to show that the Wiedemann-Franz law breaks down due to the interference of the polaron and bipolaron contributions to heat flow. The model provides a quantitative fit to magnetotransport data in the cuprates. Furthermore we are able to extract the phonon component of the thermal conductivity with the use of experimental data and the model. Our results further validate the use of a charged Bose gas model to describe normal and superconducting properties of unconventional superconductors., Comment: 9 pages, 6 figures. Submitted to Physical Review B

The techniques described in this work illustrate the type of changes which may be observed, by precise X-ray absorption spectroscopy, XAS measurements of absorbance A vs. temperature T , across a phase transition in the solid state: (i) the changes in the final states relaxation time τ, which are due to the onset of fluctuations near a phase transition at T c ; (ii) the XAS enhancement which is due to the anomalous Bragg diffraction at an absorption edge, coupled to phonon modes in the temperature interval where these are active; (iii) new allowed transitions to finite states near T c which are due to symmetry changes; (iv) changes in the bond order detected by the measurement of X-ray temperature difference absorption spectra near a phase transition: XTDAS To =XAS( T )-XAS( T 0 ) which identifies the bonds responsible for the phase transition by the progressive changes in the pair correlation term affecting the Debye–Waller factor vs. T , when no other structural changes occur, except in the vibrational modes of a specific bond. The methods have been applied to identify the phenomena that occur near the superconducting transition temperature in layer cuprates and near the metal to insulator transition in NiS 2− x Se x .

High-spin levels of [Formula: see text]Mo have been reinvestigated by analyzing the high statistics [Formula: see text]-[Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] coincidence data from the spontaneous fission of [Formula: see text]Cf taken with the Gammasphere detector array. Two bands and 30 new transitions have been identified. A potential energy surface calculation has been performed. The calculation confirmed the 3/2[Formula: see text][411] configuration of the ground state band and 5/2[Formula: see text][532] for the 346[Formula: see text]keV excited band, as assigned in the previous work. The two newly established bands were proposed to be one- and two-phonon [Formula: see text] vibrational bands coupling to the 5/2[Formula: see text][532] Nilsson orbital, respectively. Triaxial projected shell model calculations have been applied to explain the level structure and are found in good agreement with experimental data.

A rotational band was observed for the first time in $^{106}\mathrm{Nb}$ by means of \ensuremath{\gamma}-\ensuremath{\gamma}-\ensuremath{\gamma} and \ensuremath{\gamma}-\ensuremath{\gamma}-\ensuremath{\gamma}-\ensuremath{\gamma} measurements of prompt fission \ensuremath{\gamma} rays from $^{252}\mathrm{Cf}$ by using the Gammasphere multidetector array. Projected shell model and potential-energy surface calculations were performed and were compared to the experimental data of $^{106}\mathrm{Nb}$ and the previously reported $^{104}\mathrm{Nb}$. Configurations and spin-parity were assigned to the ground level, low-lying levels, and rotational bandheads of the two Nb isotopes. The new rotational band in $^{106}\mathrm{Nb}$ was interpreted as a ${K}^{\ensuremath{\pi}}\phantom{\rule{0.16em}{0ex}}=\phantom{\rule{0.16em}{0ex}}{2}^{\ensuremath{-}}$ band with a configuration \ensuremath{\pi}1/2${}^{+}$[431] \ifmmode\times\else\texttimes\fi{} \ensuremath{\nu}5/2${}^{\ensuremath{-}}$[532]. The same spin-parity and configuration were assigned to the analogous band in $^{104}\mathrm{Nb}$. \ensuremath{\pi}1/2${}^{+}$[431] \ifmmode\times\else\texttimes\fi{} \ensuremath{\nu}5/2${}^{+}$[413], ${K}^{\ensuremath{\pi}}={3}^{+}$ were assigned to the 0.66-\ensuremath{\mu}s isomer and explained the $M$2 isomeric decay to the ground in $^{106}\mathrm{Nb}$. The proton intruder orbital \ensuremath{\pi}1/2${}^{+}$[431] plays an important role in shape evolution with regard to triaxial deformation in these neutron-rich Nb isotopes.

Transport measurements have been made on Bi2Sr2CaCu2O8 single crystals in both Corbino disc and strip geometries. Pronounced differences are observed in both the resistive transition and the current-voltage characteristics in these two geometries. Surface barriers affect the behaviour of the strip and reduce the measured resistance of the vortex liquid by over two orders of magnitude with respect to the Corbino geometry. The critical current density of the Corbino disc, which reflects the true bulk critical current, is a factor of at least 20 times smaller. We conclude that the transport properties of Bi2Sr2CaCu2O8 samples in the strip geometry are dominated by SB in both the solid and liquid vortex phases over a wide range of fields and temperatures.

The unusual properties of high-temperature superconductors are reviewed. The structure and chemistry of the materials are described and the strong influence of the carrier concentration on their superconducting properties is illustrated. The temperature dependences of the resistivity, Hall effects and thermoelectric power coefficients are given. These properties distinguish the cuprates clearly from any ordinary metal known until recently. In particular the normal Boltzmann transport theory is no longer applicable. It was found that these anomalous properties of the normal phase are accompanied by superconducting order parameters of uncommon symmetry (d wave), as well as non-BCS temperature and magnetic field dependences. The observation of the normal-phase pseudogap in the density-of-states spectrum by means of specific heat and other measurements seems to offer an important way forward in understanding both the normal phase and the high-temperature superconductivity mechanism.

Deep-inelastic reactions and $\ensuremath{\gamma}$-ray spectroscopy have been used to study excited states in ${}^{195}$Au. A three-quasiparticle isomer with a mean-life of 18.6(3) $\ensuremath{\mu}$s has been assigned at 2461+$\ensuremath{\Delta}$ keV, with decays into newly identified structures. Possible configurations for the isomer are discussed including a ${J}^{\ensuremath{\pi}}$ $=$31/2${}^{\ensuremath{-}}$ intrinsic state produced by coupling the 11/2${}^{\ensuremath{-}}$[505] proton hole to the 10${}^{+}$ state obtained from the 9/2${}^{+}$[624],11/2${}^{+}$[615] two-neutron holes, expected from configuration-constrained potential-energy-surface calculations. Residual interactions are evaluated within a semi-empirical shell model basis. New lifetime information is also obtained for the 21/2${}^{+}$ and 25/2${}^{+}$ states at 1813 and 1980 keV. The relationship between these and other newly identified states and the negative-parity states in the even-even neighbors is discussed.

High Tc superconducting materials with nominal compositions of Tl1‐xBix(Sr, Ba)2Ca2Cu3O9 (0≤x≤0.5) have been investigated using x‐ray powder diffractometry and electron microscopy. It was found that Tl and Bi cations were in an ordered arrangement in the (Tl, Bi)–O atomic layer. Although the proposed supercell is 4a×4b×4c derived from the basic unit cell of the undoped TlBa2Ca2Cu3O9 (Tl‐1223), the basic two‐dimensional superlattice in the (Tl, Bi)–O layer is 2a×4b or 4a×2b with Bi cations at the center and the corner of the rectangle, giving an ideal and preferred composition with the Tl:Bi ratio of 3:1. Accordingly, the maximum Bi doping for Tl in the solid solution is 25%. The proposed model of the superstructure was supported by computer simulation of electron diffraction patterns. The mechanism of formation of the superstructure is discussed.

Low-field magnetization M(H) measurements are reported for single crystals of various high-${\mathit{T}}_{\mathit{c}}$ cuprates with different anisotropies (\ensuremath{\gamma}=${\ensuremath{\lambda}}_{\mathit{c}}$/${\ensuremath{\lambda}}_{\mathit{ab}}$, where ${\ensuremath{\lambda}}_{\mathit{c}}$ and ${\ensuremath{\lambda}}_{\mathit{ab}}$ are the c-axis and ab-plane penetration depths). For ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ (\ensuremath{\gamma}\ensuremath{\approxeq}5) and ${\mathrm{La}}_{1.89}$${\mathrm{Sr}}_{0.11}$${\mathrm{CuO}}_{4}$ (\ensuremath{\gamma}\ensuremath{\approxeq}12), qualitatively similar M(H) behavior is observed when the magnetic field is applied both perpendicular (H\ensuremath{\parallel}c) and parallel (H\ensuremath{\parallel}ab) to the ${\mathrm{CuO}}_{2}$ planes, consistent with a description of these compounds as anisotropic three-dimensional superconductors. ${\mathrm{Tl}}_{2}$${\mathrm{Ba}}_{2}$${\mathrm{CuO}}_{6+\mathrm{\ensuremath{\delta}}}$ (\ensuremath{\gamma}\ensuremath{\approxeq}25) and ${\mathrm{Bi}}_{2}$${\mathrm{Sr}}_{2}$${\mathrm{CaCu}}_{2}$O (\ensuremath{\gamma}\ensuremath{\approxeq}250), on the other hand, show significant differences in M(H) with H\ensuremath{\parallel}ab which can be attributed to the presence of Josephson screening currents across the layers. These observations imply that the nature of the interlayer coupling is determined primarily by the ratio of the out-of-plane coherence length ${\ensuremath{\xi}}_{\mathit{c}}$ to the interlayer spacing s. \textcopyright{} 1996 The American Physical Society.

Magnetic measurements have been performed on silver clad Tl‐1223 and Tl‐2223 tapes and a Tl‐1223 single crystal to study the critical current properties of these samples. The Tl‐1223 tape is shown by both magnetic and transport experiments to exhibit a highly granular nature, much more severe than that seen in the Tl‐2223 tape, and in Bi‐2223 tapes fabricated by similar rolling and pressing techniques. This characteristic is explained in terms of the poor grain alignment in the Tl‐1223 tape resulting from the spherical morphology of Tl‐1223 powders, in contrast with the micaceous and easily aligned Bi‐2223 and Bi‐2212 materials. However, evidence of a small number of strong intergrain links which remain superconducting at 77 K and 8 T is clear. The Tl‐1223 single crystal exhibits clear anisotropic behavior, and this, together with the lack of good crystallographic alignment in the tapes is used to explain the variations in irreversibility line behavior between sample forms. The ratio of the irreversibilit...

In the past years, we have made many theoretical investigations on multi-quasiparticle high- K isomeric states. A deformation-pairing-configuration self-consistent calculation has been developed by calculating a configuration-constrained multi-quasiparticle potential energy surface (PES). The specific single-particle orbits that define the high- K configuration are identified and tracked (adiabatically blocked) by calculating the average Nilsson numbers. The deformed Woods-Saxon potential was taken to give single-particle orbits. The configuration-constrained PES takes into account the shape polarization effect. Such calculations give good results on excitation energies, deformations and other structure information about multi-quasiparticle high- K isomeric states. Many different mass regions have been investigated.

PbI2 crystals have been intercalated with ammonia, methylamine (CH3NH2), ethylamine (C2H5NH2), and butylamine (C4H9NH2) for the first time. Raman spectra of these materials, and also of PbI2 intercalated with nonylamine (C9H19NH2) were obtained using an excitation wavelength of 514.531 nm. For comparison a study of the interaction of CdI2 with the same molecules is included. Raman spectroscopy in the range 10-500 cm-1 demonstrated the occurrence of a polytypic phase transition from 1 T to 3 T on intercalation of PbI2 and also that intercalation results in the breaking up of the crystal into many small crystallites. The existence of strong Pb-N interactions was demonstrated by both infrared and Raman spectroscopy.

The authors have investigated the surface chemistry of superconducting YBa2Cu3O7- delta using high-resolution electron microscopy. Specimens crushed in air showed a thick 'amorphous' coating, which would not recrystallize into the bulk structure under electron beam annealing. Instead oxide microcrystals formed within the coating. The amorphous coating layers were reduced to less than half of their original thickness when the specimens were crushed in argon, and were found to recrystallize into the YBa2Cu3O7- delta structure under the same conditions, with atomically clean surfaces produced and observed directly in the profile images. It was also found that the (001) surface terminated with the Cu-O chain. Surface reconstruction with a double atomic layer of Cu covering the (113) and (112) surfaces was confirmed by computer simulation of the profile images. Possible mechanisms of formation of the coating and clean surfaces are discussed.

A high precision differential technique is used to measure the specific heat of YBa2Cu3O7-δ for 0 ≤ ∂ ≤ 0.68 between 1.8 K and 300 K against YBa2(Cu0.93Zn0.07)3O7-δ∗ as reference, where δ∗ = 0 or 0.47. Anomalies at the superconducting transition temperature T c are observed for 0 ≤ ∂ ≤ 0.54. Careful analysis of our results show that the electronic specific heat coefficient γ(T) increases from a value close to zero at low temperatures to around 1.7 mJ/g at K2 above 200 K for all values of δ investigated. This is in contrast to the behaviour observed in Zn doped YBa2(Cu1-x Zn x )3O7 for which γ(0) increases with x to saturate at the value of normal metallic YBa2Cu3O7. These results suggest that strong magnetic correlation in the CuO2 layer is responsible for the formation of a low energy spin bound state in the insulating end of the oxygen or hole depleted YBa2Cu3O7-δ series, which is gradually replaced by the formation of the superconducting bound state as the number of hole carriers increases. Do...

The techniques described in this work illustrate the type of changes which may be observed, by precise X-ray absorption spectroscopy, XAS measurements of absorbance A vs. temperature T , across a phase transition in the solid state: (i) the changes in the final states relaxation time τ, which are due to the onset of fluctuations near a phase transition at T c ; (ii) the XAS enhancement which is due to the anomalous Bragg diffraction at an absorption edge, coupled to phonon modes in the temperature interval where these are active; (iii) new allowed transitions to finite states near T c which are due to symmetry changes; (iv) changes in the bond order detected by the measurement of X-ray temperature difference absorption spectra near a phase transition: XTDAS To =XAS( T )-XAS( T 0 ) which identifies the bonds responsible for the phase transition by the progressive changes in the pair correlation term affecting the Debye–Waller factor vs. T , when no other structural changes occur, except in the vibrational modes of a specific bond. The methods have been applied to identify the phenomena that occur near the superconducting transition temperature in layer cuprates and near the metal to insulator transition in NiS 2− x Se x .

A miniature Hall probe using a two-dimensional electron gas in an InAlAs/InGaAs heterostructure has been used to study the magnetic properties of a small Bi2Sr2CaCu2O8 single crystal, on a lateral scale of 10-20 mu m2, by placing it close to the crystal surface. The results on the irreversibility line are compared with previously reported data obtained by other techniques. The use of such detectors for real-time study has also been considered.

Two-dimensional electron gas (2DEGS), formed both at a semiconductor heterojunction and in a delta -doping layer close to a semiconductor surface, have been successfully used to probe the magnetic properties of single-crystal high-Tc superconducting YBa2Cu3O7- delta in fields up to 3 T. The results for these as-grown crystals show characteristic type-II superconductor behaviour with hysteresis due to strong flux pinning. The measurements demonstrate the usefulness and simplicity of this technique in the determination of magnetic properties, and indicate that the full potential of such superconductor-semiconductor 'heterostructures' has yet to be fully investigated.