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Constraining the X-Ray-Infrared Spectral Index of Second-timescale Flares from SGR 1935+2154 with Palomar Gattini-IR 期刊论文 OAI收割
The Astrophysical Journal, 2020, 卷号: 901, 页码: L7
作者: HXMT

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收藏 | 浏览/下载：24/0 | 提交时间：2022/02/08

Radio transient sources Magnetars Soft gamma-ray repeaters 2008 992 1471 Astrophysics - High Energy Astrophysical Phenomena Astrophysics - Instrumentation and Methods for Astrophysics Abstract: The Galactic magnetar SGR 1935+2154 has been reported to produce the first example of a bright millisecond-duration radio burst (FRB 200428) similar to the cosmological population of fast radio bursts (FRBs). The detection of a coincident bright X-ray burst represents the first observed multiwavelength counterpart of an FRB. However, the search for similar emission at optical wavelengths has been hampered by the high inferred extinction on the line of sight. Here, we present results from the first search for second-timescale emission from the source at near-infrared (NIR) wavelengths using the Palomar Gattini-IR observing system in the J band, enabled by a novel detector readout mode that allows short exposure times of ?0.84 s with 99.9% observing efficiency. With a total observing time of ?12 hr (?47,728 images) during its 2020 outburst, we place median 3Ҡlimits on the second-timescale NIR fluence of ?18 Jy ms (13.1 AB mag). The corresponding extinction-corrected limit is ?125 Jy ms for an estimated extinction of A_J = 2.0 mag. Our observations were sensitive enough to easily detect an NIR counterpart of FRB 200428 if the NIR emission falls on the same power law as observed across its radio to X-ray spectrum. We report nondetection limits from epochs of four simultaneous X-ray bursts detected by the Insight-HXMT and NuSTAR telescopes during our observations. These limits provide the most stringent constraints to date on fluence of flares at 10¹⁴ Hz, and constrain the fluence ratio of the NIR emission to coincident X-ray bursts to R_NIR ? 0.025 (fluence index ?0.35).

CYP3A4 inducer and inhibitor strongly affect the pharmacokinetics of triptolide and its derivative in rats 期刊论文 OAI收割
ACTA PHARMACOLOGICA SINICA, 2018, 卷号: 39, 期号: 8, 页码: 1386-1392
作者: Xu, Ye; Zhang, Yi-fan

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triptolide (5R)-5-hydroxytriptolide CYP3A4 ritonavir dexamethasone pharmacokinetics immunosuppressant traditional Chinese medicine

Apoptosis induction and G2/M arrest of 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone from Rubia yunnanensis in human cervical cancer HeLa cells 期刊论文 OAI收割
PHARMAZIE, 2013, 卷号: 68, 期号: 4, 页码: 293-299
作者: Zeng, Guang-Zhi; Fan, Jun-Ting; Xu, Jun-Ju; Li, Yan; Tan, Ning-Hua

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2-Methyl-1,3,6-trihydroxy-9,10-anthraquinone (MTA) one of the major components isolated from the traditional Chinese medicine Rubia yunnanensis exhibited inhibitory activity on the proliferation of several human cancer cell lines. The results from an annexin V-FITC (fluoresein-5-isothiocyanate) apoptosis assay and DNA content analysis showed that MTA exerted cytotoxicity via apoptosis induction and G2/M cell cycle arrest in human cervical carcinoma HeLa cells. Further MTA was found to induce apoptosis of HeLa cells through the mitochondria-mediated pathway. It caused the translocation of Bax to the mitochondria and release of cytochrome c into the cytosol which caused the cleavage of caspase and poly(ADP-ribose) polymerase and finally triggered the apoptosis. Furthermore the p53/p21/Cdc2-cyclin B1 signaling was found related to the G2/M arrest caused by MTA. The over-expression of p21 and down-expression of cyclin B1 caused by MTA inactivated the Cdc2-cyclin B1 complex of G2/M checkpoint and finally caused the G2/M arrest in HeLa cells. This study demonstrated that MTA is a potential anti-cancer component of R. yunnanensis a folk anti-cancer herb used in Yunnan China.

Theoretical and experimental study of the absolute configuration of helical structure of (2R,3S)-Rubiginone A(2) analog 期刊论文 OAI收割
TETRAHEDRON, 2013, 卷号: 69, 期号: 3, 页码: 1189-1194
作者: Zhou, Bei-Dou; Ren, Jie; Liu, Xin-Chun; Zhu, Hua-Jie

收藏 | 浏览/下载：34/0 | 提交时间：2013/07/24

(2R Absolute configuration DFT Optical rotation Electronic circular dichroism 3S)-Rubiginone A(2) analogue synthesis

含酰胺或砜类取代基的海藻溴代酚类化合物及制备和应用 专利 OAI收割
专利类型: 发明, 专利号: CN200910013880.5, 申请日期: 2009-07-08, 公开日期: 2009-07-08
作者: 王斌贵

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1. 一种含有酰胺或砜类取代基团的溴代酚类化合物其特征在于：结构式A或B所示其中：R1为H OH OCH3或Br R2为H OH OCH3或Br R3为CH3或C2H5。

(3aR,5R,11bR)-3,3a,5,11b-四氢-7-羟基-5-甲基-2H-呋[3,2-b]萘并[2,3-d]吡喃-2,6,11-三酮的应用 专利 OAI收割
专利类型: 发明, 专利号: CN200810017159.9, 申请日期: 2008-12-10, 公开日期: 2008-12-10
秦松; 丁玲; 张伟杰; 李富超; 哈特穆特·拉赤

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1.(3aR 5R 11bR)-3 3a 5 11b-四氢-7-羟基-5-甲基-2H-呋[3 2-b]萘并[2 3-d]吡喃-2 6 11-三酮的应用其特征在于：所述化合物在制备抗肿瘤抗生素的药中的应用。

A dynamic quantitative analysis model for network survivability 期刊论文 iSwitch采集
Chinese journal of electronics, 2008, 卷号: 17, 期号: 2, 页码: 195-199
作者: Yuqing, Zhang; Dan, Yuan

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Network survivability Quantitative analysis Anp R(3)a Cost-benefit

Characteristics of ZnMgO-based metal-semiconductor-metal photodetectors (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Photoelectronic Imaging and Detection, September 9, 2007 - September 12, 2007, Beijing, China
作者: Zhang J.; Li B.; Li B.; Li B.; Zhao Y.

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In recent years ZnMgO semiconductor alloys with a direct bandgap tunable between 3.37 eV and 7.8 eV become one of the most suitable materials for the fabrication of ultraviolet detectors. In this paper we have fabricated metal-semiconductor-metal photodetectors on 1-m thick Zn 0.8Mg0.2O films. The interdigital metal electrodes are 500 m long and 5 m wide with an interelectrode spacing 2 m 5 m and 10 m respectively. Zn0.8Mg0.2O films were grown on quartz by ratio frequency magnetron sputtering at 500C. Dark current spectral responsivity and pulse response were carried out for the devices with different finger pitches. All the photodetectors showed the peak responsivity at 330 nm and the ultraviolet-visible rejection ratio (R330 nm/R400 nm) is more than four orders of magnitude at 3 V bias. For the device with 2 m finger pitch the detectivity was calculated as 4.21011 cm Hz 1/2/W at 330 nm. Furthermore the transient response measurement for all devices revealed similar rise time of 10 ns. The 90%-10% fall times are 130 ns 170 ns and 230 ns for the devices with different finger pitches of 2 m 5 m and 10 m respectively..

A novel norditerpene from Eupatorium adenophorum 期刊论文 OAI收割
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES, 2007, 卷号: 62, 期号: 4, 页码: 577-579
作者: Wang, Ming-Zhong; Cai, Xiang-Hai; Du, Guo-Shun; Luo, Xiao-Dong

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Eupatorium Adenophorum (4ar Biodegradation 7r Clerodane 8s 8ar)-1 2 4a 5 6 7 8 8a-octahydro-8-[3-methylenebut-4-alyl]-4 4a 7 8-tetramethylnaphthalen-2(Ih)-one

Low drive-voltage and high-bandwidth electro-optic modulators based on BaTiO3 thin-film waveguides (EI CONFERENCE) 会议论文 OAI收割
Science and Technology of Dielectrics for Active and Passive Photonic Devices - 210th Electrochemical Society Meeting, October 29, 2006 - November 3, 2006, Cancun, Mexico
Sun D. G.; Fu X. H.; Liu Z. F.; Ho S. T.; Wessels B. W.

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We investigated electro-optic modulator structures to target low drive voltage high-speed modulation and small device size with c-axis grown BaTiO3/MgO ferro-electric thin films. In this study the calculations are focused on the ideal thin film with a quadratic relation between the half-wave drive voltage V and the interaction length L in the electro-optic modulation case we obtained in previous work. With the quadratic electro-optic modulating relation and the optimal rib waveguide structure of BaTiO3/MgO thin films the frequency-voltage-size performances for 2.5GHz 10GHz 40GHz and 100GHz modulation bandwidths have been obtained under half-wave drive voltages of 0.8V 1.6V 3.0V and 4.8V respectively for the ideal film with r51=730 pm/V at 1550nm wavelength where both the phase velocity matching condition and the conductor induced microwave attenuation are considered. The required device lengths to achieve these four typical values of modulation bandwidth are 3.3 mm 0.8 mm 0.4 mm and 0.2 mm respectively. With the c-axis grown BaTiO3/MgO crystal thin films and the quadratic electro-optic modulating relation an electro-optic coefficient of reff=180 pm/V for the c-axis grown BaTiO3/MgO ferro-electric thin films was measured which is relatively far from the ideal value of r51=560 pm/V. copyright The Electrochemical Society.