OBJECTIVE: To identify the constituents in Shuanghuanglian injection(SHLI) that correlate with anaphylactoid reaction.METHODS: Chemical fingerprints of 10 batches SHLI samples were determined by High Performance Liqui...OBJECTIVE: To identify the constituents in Shuanghuanglian injection(SHLI) that correlate with anaphylactoid reaction.METHODS: Chemical fingerprints of 10 batches SHLI samples were determined by High Performance Liquid Chromatography(HPLC), and further investigated by similarity analysis. Combined with optical microscopy, both anaphylactoid experiments and confirmatory assay were displayed in Rat basophil leukemia cells(RBL-2H3) to obtain the histamine release inducing by SHLI. The content of histamine was tested by Enzyme-Linked Immuno Sorbent As-say method. Partial least squares regression(PLSR)method and HPLC-DAD-ESI-MSntechnology were conducted to analyze constituents in SHLI involving anaphylactoid reaction.RESULTS: The results of spectrum and effect relationships showed that the eight constituents were positively correlated with anaphylactoid reaction.Among which, nearly 90% of them were identified as baicalin and rutin with PLSR and HPLC-DAD-ESI-MSn. This result was in accordance with confirmatory assay on RBL-2H3 cells.CONCLUSION: Baicalin and rutin from SHLI were the main constituents involving anaphylactoid reaction.展开更多
After the introduction of the ionization-injection scheme in laser wake field acceleration and of related high-quality electron beam generation methods,such as two-color and resonant multi-pulse ionization injection(R...After the introduction of the ionization-injection scheme in laser wake field acceleration and of related high-quality electron beam generation methods,such as two-color and resonant multi-pulse ionization injection(Re MPI),the theory of thermal emittance has been used to predict the beam normalized emittance obtainable with those schemes.We recast and extend such a theory,including both higher order terms in the polynomial laser field expansion and non-polynomial corrections due to the onset of saturation effects on a single cycle.Also,a very accurate model for predicting the cycle-averaged distribution of the extracted electrons,including saturation and multi-process events,is proposed and tested.We show that our theory is very accurate for the selected processes of Kr^(8+→10+) and Ar^(8+→10+),resulting in a maximum error below 1%,even in a deep-saturation regime.The accurate prediction of the beam phase-space can be implemented,for example,in laser-envelope or hybrid particle-in-cell(PIC)/fiuid codes,to correctly mimic the cycle-averaged momentum distribution without the need for resolving the intra-cycle dynamics.We introduce further spatial averaging,obtaining expressions for the whole-beam emittance fitting with simulations in a saturated regime,too.Finally,a PIC simulation for a laser wakefield acceleration injector in the Re MPI configuration is discussed.展开更多
The degradation mechanism of enhancement-mode Al Ga N/Ga N high electron mobility transistors（HEMTs） fabricated by fluorine plasma ion implantation technology is one major concern of HEMT＇s reliability. It is obser...The degradation mechanism of enhancement-mode Al Ga N/Ga N high electron mobility transistors（HEMTs） fabricated by fluorine plasma ion implantation technology is one major concern of HEMT＇s reliability. It is observed that the threshold voltage shows a significant negative shift during the typical long-term on-state gate overdrive stress. The degradation does not originate from the presence of as-grown traps in the Al Ga N barrier layer or the generated traps during fluorine ion implantation process. By comparing the relationships between the shift of threshold voltage and the cumulative injected electrons under different stress conditions, a good agreement is observed. It provides direct experimental evidence to support the impact ionization physical model, in which the degradation of E-mode HEMTs under gate overdrive stress can be explained by the ionization of fluorine ions in the Al Ga N barrier layer by electrons injected from 2DEG channel.Furthermore, our results show that there are few new traps generated in the Al Ga N barrier layer during the gate overdrive stress, and the ionized fluorine ions cannot recapture the electrons.展开更多
Ionization-induced electron injection in laser wakefield accelerators, which was recently proposed to lower the laser intensity threshold for electron trapping into the wake wave, has the drawback of generating electr...Ionization-induced electron injection in laser wakefield accelerators, which was recently proposed to lower the laser intensity threshold for electron trapping into the wake wave, has the drawback of generating electron beams with large and continuous energy spreads, severely limiting their future applications. Complex target designs based on separating the electron trapping and acceleration stages were proposed as the only way for getting small energy-spread electron beams. Here, based on the self-truncated ionization-injection concept which requires the use of unmatched laser–plasma parameters and by using tens of TW laser pulses focused onto a gas jet of helium mixed with low concentrations of nitrogen, we demonstrate single-stage laser wakefield acceleration of multi-hundred MeV electron bunches with energy spreads of a few percent. The experimental results are verified by PIC simulations.展开更多
Docetaxel is a member of taxan family of antineoplastic agents widely used in cancer chemotherapy. However, application of conventional chemotherapy with commercial formulation has been accompanied with matters of con...Docetaxel is a member of taxan family of antineoplastic agents widely used in cancer chemotherapy. However, application of conventional chemotherapy with commercial formulation has been accompanied with matters of concern regarding drug’s biodistribution, pharmacokinetics, and pharmacodynamics. Polymeric nanoparticles have been widely used as unique drug delivery vehicles to circumvent such problems. Docetaxel-loaded poly (lactide-co-glycolide) (PLGA) and poly (lactide-co-glycolide)-poly (ethylene glycol) (PLGA-PEG) nanoparticles fit well in modifying drug’s pharmacokinetic characteristics as intravenous (IV) sustained-release delivery vehicles. In such circumstances, characterization of nanoparticles in terms of their drug-payload would be a necessary step. The majority of studies have used HPLC analysis method for docetaxel quantitation in polymeric nanoparticles. Herein, a rapid ESI-MS/MS method for quantitative analysis of docetaxel in polymeric matrices of PLGA and PLGA-PEG nanoparticles through direct injection to mass spectrometer has been developed and validated. The assay was validated over a range of 3.9 - 1000 ng/ml and 125 - 16,000 ng/ml. Samples were directly injected to the instrument through an isocratic elution (0.1% formic acid in methanol) and detection was performed on a Hybrid Triple Quadrupole/Linear Ion trap mass spectrometer with multiple reaction monitoring (MRM) mode via positive electrospray ionization (ESI) source. The run time and retention time were 2 and 0.6 minutes respectively. The method demonstrated acceptable level of accuracy and precision and was successfully applied for quantitative analysis of docetaxel in polymeric nanoparticles of PLGA and PLGA-PEG.展开更多
A gas injector was designed for the 400 J/pulse prototype of the planar inductive pulsed plasma thruster（IPPT） developed by the National University of Defense Technology（NUDT_IPPTx）.As the gas puff distribution ov...A gas injector was designed for the 400 J/pulse prototype of the planar inductive pulsed plasma thruster（IPPT） developed by the National University of Defense Technology（NUDT_IPPTx）.As the gas puff distribution over the coil surface is critical to the NUDT_IPPTx functioning efficiently, a fast ionization gauge was developed to investigate the neutral gas pressure profiles to seek the critical time when the thruster is ignited. The gauge was calibrated for argon by using a capacitance manometer. Time-resolved pressure profiles have been acquired in the condition of the gas puff mass matching with the discharge energy and the drive coil parameters of the NUDT_IPPTx. It is demonstrated that the gas injector can supply a gas puff with a sufficiently steep（dp/dt？≈？770 kPa s-1） leading and trailing edge, and the gas puff can be compressed against the drive coil as expected. The critical ignition moment is considered to appear at some instant between 525 μs and 650 μs after the valve trigger.展开更多
A new scheme is proposed to improve the electron beam quality of ionization-induced injection by tailoring gas profile in laser wakefield acceleration.Two-dimensional particle-in-cell simulations show that the ionizat...A new scheme is proposed to improve the electron beam quality of ionization-induced injection by tailoring gas profile in laser wakefield acceleration.Two-dimensional particle-in-cell simulations show that the ionization-induced injection mainly occurs in high-density stage and automatically truncates in low-density stage due to the decrease of the wakefield potential difference.The beam loading can be compensated by the elongated beam resulting from the density transition stage.The beam quality can be improved by shorter injection distance and beam loading effect.A quasi-monoenergetic electron beam with a central energy of 258 MeV and an energy spread of 5.1%is obtained under certain laser-plasma conditions.展开更多
基于0.18μm CMOS工艺开发了抗总剂量辐射加固技术,制备的1.8 V NMOS器件常态性能良好,器件在500 krad(Si)剂量点时,阈值电压与关态漏电流无明显变化。研究器件的热载流子效应,采用体电流Isub/漏电流Id模型评估器件的HCI寿命,寿命达到5...基于0.18μm CMOS工艺开发了抗总剂量辐射加固技术,制备的1.8 V NMOS器件常态性能良好,器件在500 krad(Si)剂量点时,阈值电压与关态漏电流无明显变化。研究器件的热载流子效应,采用体电流Isub/漏电流Id模型评估器件的HCI寿命,寿命达到5.75年,满足在1.1 Vdd电压下工作寿命大于0.2年的规范要求。探索总剂量辐射效应与热载流子效应的耦合作用,对比辐照与非辐照器件的热载流子损伤,器件经辐照并退火后,受到的热载流子影响变弱。评估加固工艺对器件HCI可靠性的影响,结果表明场区总剂量加固工艺并不会造成热载流子损伤加剧的问题。展开更多
基金Supported by National Science Foundation of China(the Research of Repair Mechanisms Based on the Neural Stem Cells Niche Regulation of Chinese Medicine After Brain Damage,No.81373830)National ScienceTechnology Major Projects for"Major New Drugs Innovation and Development"(Technology Reform of Shuanghuanglian Powder Injection,No.2011ZX09201-201-15)
文摘OBJECTIVE: To identify the constituents in Shuanghuanglian injection(SHLI) that correlate with anaphylactoid reaction.METHODS: Chemical fingerprints of 10 batches SHLI samples were determined by High Performance Liquid Chromatography(HPLC), and further investigated by similarity analysis. Combined with optical microscopy, both anaphylactoid experiments and confirmatory assay were displayed in Rat basophil leukemia cells(RBL-2H3) to obtain the histamine release inducing by SHLI. The content of histamine was tested by Enzyme-Linked Immuno Sorbent As-say method. Partial least squares regression(PLSR)method and HPLC-DAD-ESI-MSntechnology were conducted to analyze constituents in SHLI involving anaphylactoid reaction.RESULTS: The results of spectrum and effect relationships showed that the eight constituents were positively correlated with anaphylactoid reaction.Among which, nearly 90% of them were identified as baicalin and rutin with PLSR and HPLC-DAD-ESI-MSn. This result was in accordance with confirmatory assay on RBL-2H3 cells.CONCLUSION: Baicalin and rutin from SHLI were the main constituents involving anaphylactoid reaction.
基金the financial contribution from the CNR funded Italian Research Network ELI-Italy (D.M. No. 631 08.08.2016)from the EU Horizon 2020 Research and Innovation Program under Grant Agreement No. 653782 Eu PRAXIA。
文摘After the introduction of the ionization-injection scheme in laser wake field acceleration and of related high-quality electron beam generation methods,such as two-color and resonant multi-pulse ionization injection(Re MPI),the theory of thermal emittance has been used to predict the beam normalized emittance obtainable with those schemes.We recast and extend such a theory,including both higher order terms in the polynomial laser field expansion and non-polynomial corrections due to the onset of saturation effects on a single cycle.Also,a very accurate model for predicting the cycle-averaged distribution of the extracted electrons,including saturation and multi-process events,is proposed and tested.We show that our theory is very accurate for the selected processes of Kr^(8+→10+) and Ar^(8+→10+),resulting in a maximum error below 1%,even in a deep-saturation regime.The accurate prediction of the beam phase-space can be implemented,for example,in laser-envelope or hybrid particle-in-cell(PIC)/fiuid codes,to correctly mimic the cycle-averaged momentum distribution without the need for resolving the intra-cycle dynamics.We introduce further spatial averaging,obtaining expressions for the whole-beam emittance fitting with simulations in a saturated regime,too.Finally,a PIC simulation for a laser wakefield acceleration injector in the Re MPI configuration is discussed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61334002,61106106,and 61474091)the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory(Grant No.ZHD201206)+1 种基金the New Experiment Development Funds for Xidian University,China(Grant No.SY1213)the Scientific Research Foundation for the Returned Overseas Chinese Scholars
文摘The degradation mechanism of enhancement-mode Al Ga N/Ga N high electron mobility transistors（HEMTs） fabricated by fluorine plasma ion implantation technology is one major concern of HEMT＇s reliability. It is observed that the threshold voltage shows a significant negative shift during the typical long-term on-state gate overdrive stress. The degradation does not originate from the presence of as-grown traps in the Al Ga N barrier layer or the generated traps during fluorine ion implantation process. By comparing the relationships between the shift of threshold voltage and the cumulative injected electrons under different stress conditions, a good agreement is observed. It provides direct experimental evidence to support the impact ionization physical model, in which the degradation of E-mode HEMTs under gate overdrive stress can be explained by the ionization of fluorine ions in the Al Ga N barrier layer by electrons injected from 2DEG channel.Furthermore, our results show that there are few new traps generated in the Al Ga N barrier layer during the gate overdrive stress, and the ionized fluorine ions cannot recapture the electrons.
基金supported by the National ‘973’ Program of China under Grant No.2013CBA01504supported by Shanghai Supercomputer Center and the center for high performance computing at Shanghai Jiao Tong University
文摘Ionization-induced electron injection in laser wakefield accelerators, which was recently proposed to lower the laser intensity threshold for electron trapping into the wake wave, has the drawback of generating electron beams with large and continuous energy spreads, severely limiting their future applications. Complex target designs based on separating the electron trapping and acceleration stages were proposed as the only way for getting small energy-spread electron beams. Here, based on the self-truncated ionization-injection concept which requires the use of unmatched laser–plasma parameters and by using tens of TW laser pulses focused onto a gas jet of helium mixed with low concentrations of nitrogen, we demonstrate single-stage laser wakefield acceleration of multi-hundred MeV electron bunches with energy spreads of a few percent. The experimental results are verified by PIC simulations.
文摘Docetaxel is a member of taxan family of antineoplastic agents widely used in cancer chemotherapy. However, application of conventional chemotherapy with commercial formulation has been accompanied with matters of concern regarding drug’s biodistribution, pharmacokinetics, and pharmacodynamics. Polymeric nanoparticles have been widely used as unique drug delivery vehicles to circumvent such problems. Docetaxel-loaded poly (lactide-co-glycolide) (PLGA) and poly (lactide-co-glycolide)-poly (ethylene glycol) (PLGA-PEG) nanoparticles fit well in modifying drug’s pharmacokinetic characteristics as intravenous (IV) sustained-release delivery vehicles. In such circumstances, characterization of nanoparticles in terms of their drug-payload would be a necessary step. The majority of studies have used HPLC analysis method for docetaxel quantitation in polymeric nanoparticles. Herein, a rapid ESI-MS/MS method for quantitative analysis of docetaxel in polymeric matrices of PLGA and PLGA-PEG nanoparticles through direct injection to mass spectrometer has been developed and validated. The assay was validated over a range of 3.9 - 1000 ng/ml and 125 - 16,000 ng/ml. Samples were directly injected to the instrument through an isocratic elution (0.1% formic acid in methanol) and detection was performed on a Hybrid Triple Quadrupole/Linear Ion trap mass spectrometer with multiple reaction monitoring (MRM) mode via positive electrospray ionization (ESI) source. The run time and retention time were 2 and 0.6 minutes respectively. The method demonstrated acceptable level of accuracy and precision and was successfully applied for quantitative analysis of docetaxel in polymeric nanoparticles of PLGA and PLGA-PEG.
基金supported by National Natural Science Foundation of China(No.51306203)the Natural Science Foundation of Hunan Province(No.2018JJ3592)
文摘A gas injector was designed for the 400 J/pulse prototype of the planar inductive pulsed plasma thruster（IPPT） developed by the National University of Defense Technology（NUDT_IPPTx）.As the gas puff distribution over the coil surface is critical to the NUDT_IPPTx functioning efficiently, a fast ionization gauge was developed to investigate the neutral gas pressure profiles to seek the critical time when the thruster is ignited. The gauge was calibrated for argon by using a capacitance manometer. Time-resolved pressure profiles have been acquired in the condition of the gas puff mass matching with the discharge energy and the drive coil parameters of the NUDT_IPPTx. It is demonstrated that the gas injector can supply a gas puff with a sufficiently steep（dp/dt？≈？770 kPa s-1） leading and trailing edge, and the gas puff can be compressed against the drive coil as expected. The critical ignition moment is considered to appear at some instant between 525 μs and 650 μs after the valve trigger.
基金supported by the National Natural Science Foundation of China(Grant Nos.12005297,11975308,and 11775305)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA25050200)+2 种基金the Fund of Science Challenge Project(Grant No.TZ2018001)Natural Science Foundation of Hunan Province,China(Grant No.2020JJ5651)the Fund of the State Key Laboratory of Laser Interaction with Matter(Grant No.SKLLIM1908)。
文摘A new scheme is proposed to improve the electron beam quality of ionization-induced injection by tailoring gas profile in laser wakefield acceleration.Two-dimensional particle-in-cell simulations show that the ionization-induced injection mainly occurs in high-density stage and automatically truncates in low-density stage due to the decrease of the wakefield potential difference.The beam loading can be compensated by the elongated beam resulting from the density transition stage.The beam quality can be improved by shorter injection distance and beam loading effect.A quasi-monoenergetic electron beam with a central energy of 258 MeV and an energy spread of 5.1%is obtained under certain laser-plasma conditions.
