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961.
从课标、概念组织结构、教学资料对新旧人教版选修“反应热”内容进行对比分析,研究发现:(1)新课标在内容上更加强调“反应热”概念的学科理解,渗透变化观与守恒观等基本观念,突出学习素材的重要性;(2)新教材在内容组织上厘清了“反应热”“焓变”“能量转化”等核心概念之间的关系,重视对“反应热”内容的结构化认识;(3)新教材在图片、实验、习题增强了情境性与科学性。建议教师在教学中增进对“反应热”的学科理解,运用概念构图策略促进学生知识结构化,创设真实情境提高学生的问题解决能力,培养化学学科核心素养。 相似文献
962.
964.
A novel, highly sensitive, simple, and rapid strategy was designed and developed for simultaneous determination of cabozantinib (CBZ) as an anticancer agent and its main metabolites including monohydroxy sulfate (EXEL-1646), N-oxide (EXEL-5162(, amide cleavage product (EXEL-5366), and 6-desmethyl amide cleavage product sulfate) EXEL-1644). Measurements were done through a micellar liquid chromatography (MLC) method coupled with fluorescence detection. The high-performance liquid chromatography (HPLC) was performed using a Kinetex C18 100 Å column as well as acetonitrile, cetyltrimethylammonium bromide (CTAB; 0.2 mol.L?1), and tris buffer (pH 8.5) solutions as the mobile phase at a 40:50:10 (v/v) ratio. The method’s linearity (20 to 700 ng.mL?1), limit of detection (LOD; 2.11 to 3.69 ng.mL?1), limit of quantification (LOQ; 20 to 30 ng.mL?1), intra- and inter-day precisions (RSD < 4.00%), selectivity, recovery, and robustness were fully evaluated. According to the obtained results, the developed method can be used for simple and rapid (~35 min) quantification of CBZ as an anticancer drug and its major metabolites in human serum samples with high sensitivity and low cost. 相似文献
965.
Qi Cong Ding Zi Tu Jianglin Wang Yuxing Wang Yinjie 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2269-2284
Journal of Thermal Analysis and Calorimetry - As high heat dissipation has increasingly become the primary factor restricting the capability of electronic elements, and the high temperature of the... 相似文献
966.
We analyze the recently found inequality for eigenvalues of the density matrix and purity parameters describing either a bipartite-system state or a single-qudit state. We rewrite the Minkowski-type trace inequality for the density matrices of the qudit states in terms of the purity parameters and discuss the properties of the inequality obtained, paying special attention to the X-states of two qubits and a single qudit. Also we study the relation of the purity inequalities obtained with the entanglement. 相似文献
967.
Hu Pan Renpeng Yan Xudong Li Xin Fa Yufei Ma Rongwei Fan Xin Yu Deying Chen 《Journal of Russian Laser Research》2016,37(3):259-264
We present a compact high-peak-power, high-repetition-rate burst-mode laser from a master-oscillator power amplifier (MOPA) at 1064 nm for laser-based measurement applications. The oscillator is an 808 nm pulsed laser diode side-pumped acousto-optical (A-O) Q-switched Nd:YAG laser at repetition rates ranging from 10–100 kHz, producing a pulse train with a pulse number of 2–25. The maximum output energy of the oscillator is 15.6 mJ at 10 kHz, whereas it is 1.7 mJ at 100 kHz. After twostage amplifiers, a single-pulse energy of 85.2 mJ with a pulse-width of 14.5 ns is achieved at 10 kHz, which produces a peak power of 6.1 MW. At 100 kHz, the total burst energy reaches 220 mJ with a single-pulse energy of 8.8 mJ in the pulse burst laser system. 相似文献
968.
Zhouqiang Zhang Shuhai Jia Fei Wang Yonglin Wang 《Journal of Russian Laser Research》2016,37(3):285-290
We study quartz tuning fork (QTF) characteristics using a 532 nm semiconductor laser with a power of 39 mW and calculate QTF vibrations caused by thermal noise and disturbance of the air using the equipartition theorem; the vibration value is about 1.152 Pm. The signal-to-noise ratio and QTF resonance amplitude acquired experimentally are 104.56 and 214.75 Pm, respectively. In addition, we develop a new photo-acoustic spectroscopic system for detection of trace acetylene using a CW diode laser source with distributed feedback operating near 1,532 nm, measure the absorption spectrum of acetylene employing this system, and show that the method elaborated is more sensitive than photoelectric detectors that provides new directions for research in photo-acoustic spectroscopy. 相似文献
969.
We review the notion of weighted quantum entropy and consider the weighted quantum entropy for bipartite and noncomposite quantum systems. We extend the subadditivity condition, the inequality known for the weighted entropy information, to the case of indivisible qudit system, such as a qutrit. We discuss the new inequality for the qutrit density matrix for different weights and states, as well as the role of weighted entropy with respect to nonlinear quantum channels. 相似文献
970.
We present a sophisticated optical design method for reducing the number of photodetectors for a specific sensing task. The chosen design parameter is the point spread function, and the selected task is object recognition. The point spread function is optimized iteratively with a genetic algorithm for object recognition based on a neural network. In the experimental demonstration, binary classification of face and non-face datasets was performed with a single measurement using two photodetectors. A spatial light modulator operating in the amplitude modulation mode was provided in the imaging optics and was used to modulate the point spread function. In each generation of the genetic algorithm, the classification accuracy with a pattern displayed on the spatial light modulator was fed-back to the next generation to find better patterns. The proposed method increased the accuracy by about 30 % compared with a conventional imaging system in which the point spread function was the delta function. This approach is practically useful for compressing the cost, size, and observation time of optical sensors in specific applications, and robust for imperfections in optical elements. 相似文献