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61.
Eco-friendly lead-free organic–inorganic manganese halides (OIMHs) have attracted considerable attention in various optoelectronic applications because of their superior optical properties and flexible solution processibility. Herein, we report a novel pseudo-2D layered OIMH (MTP)2MnBr4 (MTP: methyltriphenylphosphonium), which exhibits intense green emission under UV/blue or X-ray excitation, with a near-unity photoluminescence quantum yield, high resistance to thermal quenching (I150 °C=84.1 %) and good photochemical stability. These features enable (MTP)2MnBr4 as an efficient green phosphor for blue-converted white light-emitting diodes, demonstrating a commercial-level luminous efficiency of 101 lm W−1 and a wide color gamut of 116 % NTSC. Moreover, these (MTP)2MnBr4 crystals showcase outstanding X-ray scintillation properties, delivering a light yield of 67000 photon MeV−1, a detection limit of 82.4 nGy s−1, and a competitive spatial resolution of 6.2 lp mm−1 for X-ray imaging. This work presents a new avenue for the exploration of eco-friendly luminescent OIMHs towards multifunctional light-emitting applications.  相似文献   
62.
A novel labeling reagent 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) coupling to liquid chromatography with electrospray ionization mass spectrometry for the detection of carbohydrates from the derivatized rape bee pollen samples is reported. Carbohydrates are derivatized to their bis-NMP-labeled derivatives. Derivatives showed an intense protonated molecular ion at m/z [M+H]+ in positive-ion detection mode. The mass-to-charge ratios of characteristic fragment ions at m/z 473.0 could be used for the accurately qualitative analysis of carbohydrates. This characteristic fragment ion is from the cleavage of C2–C3 bond in carbohydrate chain giving the specific fragment ions at m/z [MH-C m H2m+1O m -H2O]+ for pentose, hexose and glyceraldehydes and at m/z [MH-C m H2m-1O m+1-H2O]+ for alduronic acids such as galacturonic acid and glucuronic acid (m = n ? 2, n is carbon number of carbohydrate). No interferences for all aliphatic and aromatic aldehydes presented in natural environmental samples were observed due to the highly specific parent mass-to-charge ratio and the characteristic fragment ions. The method, in conjunction with a gradient elution, offered a baseline resolution of carbohydrate derivatives on a reversed-phase Hypersil ODS-2 column. The carbohydrates such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose and fucose can successfully be detected.  相似文献   
63.
利用锁相环技术,通过调频方式,实现音频信号的调制、解调,设计一种可以选择使用耳机或扬声器的无线语音传输系统.系统利用电路实现语音的通信和信息转发,可实现对语音实时无失真传输,系统实现对音频信号的无线通信的功能.  相似文献   
64.
将62例脑梗塞患者随机分为两组,并分别用激光血管内照射(ILIB)及尿激酶进行治疗,继而对两组疗效进行对比性观察、测试及评估。文末对ILIB的作用机理进行了分析。  相似文献   
65.
Extending the work of Lewis and Leach on classical invariants for solving the classical equation of motion in one-dimensional system, the quantum invariants in polynomial form of momentum are obtained. The involved Hamiltonian is time-dependent and quadratic in momentum.  相似文献   
66.
Novel MnO nano- and microparticles including spherical nanoparticles and various micropolyhedra of pyramid-like, truncated rectangular pyramid-like, cubic, and rhombic dodecahedral particles, were controllably synthesized via solid-state thermolysis of inorganic core containing molecular clusters [Mn12O12(O2CR)16(H2O)4] (R=C6H5, CH3, and C6H5OCH2) in a conventional horizontal tube furnace. Among them, pyramid-like, truncated rectangular pyramid-like, cubic, and rhombic dodecahedral MnO submicroscale particles were reported for the first time. The products were characterized by XRD, XPS, Raman spectrum, SEM, EDX, TEM and HRTEM. During the reaction process, thermolysis temperature, reaction time, and different molecular clusters {Mn12} precursors with different organic ligands as well play important roles in determining the sizes and shapes of the final products. The formed MnO nanospheres from [Mn12O12(O2CC6H5)16(H2O)4] at 400 °C for 10 h exhibited weak ferromagnetic behavior at low temperature which may be due to the size-effect of nanomaterials. Furthermore, the possible formation mechanism was also discussed.  相似文献   
67.
High-performance liquid chromatography with tandem mass spectrometry has been used for rapid, specific, and sensitive analysis of busulfan in human plasma. Busulfan-d8 was used as internal standard. Analysis was performed on a C18 column (50 mm × 2.1 mm, 3.5-µm particles) with water–methanol 80:20 (v/v) as mobile phase at a flow-rate of 0.30 mL min?1. Detection was by tandem triple–quadrupole mass spectrometry with turbo ion-spray ionization. Linear calibration plots were obtained over the concentration range 1.096–1,096 ng mL?1. The assay is ideally suited to monitoring of busulfan and determination of its pharmacokinetic data.  相似文献   
68.
A correction vector method within the multireference determinant single and double configuration interaction approximation coupled with the semiempirical intermediate neglect of differential overlap Hamiltonian has been developed for the computation of single and multiphoton absorption spectra of conjugated molecules. We study the effect of pi conjugation on these properties in the extended rylenebis(dicarboximide)s. The one-, two-, and three-photon absorption cross sections of the lowest-lying excited states show a power law dependence on the conjugation length, with exponents of about 1.3, 2.6, and 5.6, respectively. The maximum value of the three-photon absorption cross section in these molecules is calculated to be 1.06x10(-78) cm6 s2photon2 for photon energy at 0.57 eV.  相似文献   
69.
In this paper, we address the problem of carrier frequency offset (CFO) estimation for orthogonal frequency division multiplexing (OFDM) systems with multi-antenna receiver. The received signal can be reconstructed to form data model with multi-invariance property, and then a multi-invariance MUSIC algorithm for CFO estimation is proposed. This algorithm has better performance of CFO estimation than ESPRIT method, multi-invariance ESPRIT method and trilinear decomposition algorithm, and also qualifies the estimation for both integer CFO and fractional CFO. Simulation results illustrate validity of this algorithm.  相似文献   
70.
选用天然黑色海水珍珠、活性超级黑染色黑珍珠、辐照处理黑珍珠和硝酸盐染色黑珍珠,对其进行拉曼光谱测试、紫外可见吸收光谱测试的研究。两项测试表明:拉曼光谱中天然黑色海水珍珠、硝酸银染色和辐照黑珍珠均出现1080cm-1和699cm-1文石的特征拉曼峰,辐照黑珍珠荧光背景较强,染料染色黑珍珠的出峰位置与所使用染料的类型有关;紫外可见吸收光谱中,天然黑色海珍珠出现284nm和357nm两个吸收峰,染料活性超级黑染色珍珠出现380nm吸收峰,应为357nm吸收峰发生红移所致,银盐染色黑珍珠和辐照处理黑珍珠紫外区吸收峰消失。根据拉曼和紫外可见光谱特征,可以快速、无损地鉴定天然黑色珍珠和各种着色黑珍珠。  相似文献   
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