[en] The effects of annealing on structure and laser-induced damage threshold (LIDT) of Ta₂O₅/SiO₂ dielectric mirrors were investigated. Ta₂O₅/SiO₂ multilayer was prepared by ion beam sputtering (IBS), then annealed in air under the temperature from 100 to 400 deg. C. Microstructure of the samples was characterized by X-ray diffraction (XRD). Absorption of the multilayer was measured by surface thermal lensing (STL) technique. The laser-induced damage threshold was assessed using 1064 nm free pulsed laser at a pulse length of 220 μs. It was found that the center wavelength shifted to long wavelength gradually as the annealing temperature increased, and kept its non-crystalline structure even after annealing. The absorbance of the reflectors decreased after annealing. A remarkable increase of the laser-induced damage threshold was found when the annealing temperature was above 250 deg. C

[en] Neutrino research is of great importance for particle physics, astrophysics and cosmology. A new global trigger scheme with online vertex fitting has been proposed, aiming at the ultra-low anti-neutrino energy threshold as down to 0.2MeV which is essential for the study of solar neutrino and supernova elastic scattering neutrinos on burst. With the scheme, the time of flight difference of photons fly through the liquid media from the interaction point to the surface of central detector can be corrected online, the trigger window to cover the whole spread of a specific neutrino generated photons can be significantly reduced which lessen the integrated dark noise introduced from the large amount of PMT devices hence a lower energy threshold can be achieved. The scheme is compatible, flexible and easy to implement, it can effectively help the low energy neutrino research topics. (author)

[en] The effect of charge collection time on the trapezoidal shaping effect, statistical methods and methods to reduce the time effect of charge collection are discussed. The relationship between charge collection time and trapezoidal shaping pulse width is found by theoretical derivation. The calculation formula of charge collection time and the method of amplitude extraction correction are given. The actual trapezoidal pulse width was used to reverse the charge collection time, and the results were found to be in good agreement with the actual situation. The energy spectrum of the ⁶⁰Co source was tested. The energy resolutions of the two characteristic peaks of ⁶⁰Co were 1.9 keV and 2.0 keV, respectively, which verified the effect of amplitude extraction correction on improving energy resolution. (authors)

[en] The papers introduce the hardware and software design of 100 Mbps Ethernet control module, which is applied in Nuclear Data Acquisition System of Tsinghua Tongfang. The future improvements of the system is also discussed. At present the module is based on the 32 bit high-performance MPU ColdFire5307 and uClinux operating system is embedded. (authors)

[en] A FPGA based data acquisition readout board has been developed for the LHCb detectors. With optical or analogue daughter cards, it can readout data from several different off-detector electronics. The data synchronization, buffering, pre-processing, zero-suppression and many interfaces to memory chips and communication buses are all implemented by the FPGA in VHDL code. The board sends data out via a 4 channel Gigabit Ethernet adapter. The TELL1 can accepts 24 optical links running at 1.6 GHz and provides for the analogue option 64 10-bit ADC channels sampling at 40 MHz. (authors)

[en] Alzheimer's disease is a representative age-related neurodegenerative disease that could result in loss of memory and cognitive deficiency. However, the precise onset time of Alzheimer's disease affecting neuronal circuits and the mechanisms underlying the changes are not clearly known. To address the neuroanatomical changes during the early pathologic developing process, we acquired the neuronal morphological characterization of AD in APP/PS1 double-transgenic mice using the Micro-Optical Sectioning Tomography system. We reconstructed the neurons in 3D datasets with a resolution of 0.32 × 0.32 × 1 μm and used the Sholl method to analyze the anatomical characterization of the dendritic branches. The results showed that, similar to the progressive change in amyloid plaques, the number of dendritic branches were significantly decreased in 9-month-old mice. In addition, a distinct reduction of dendritic complexity occurred in third and fourth-order dendritic branches of 9-month-old mice, while no significant changes were identified in these parameters in 6-month-old mice. At the branch-level, the density distribution of dendritic arbors in the radial direction decreased in the range of 40–90 μm from the neuron soma in 6-month-old mice. These changes in the dendritic complexity suggest that these reductions contribute to the progressive cognitive impairment seen in APP/PS1 mice. This work may yield insights into the early changes in dendritic abnormality and its relevance to dysfunctional mechanisms of learning, memory and emotion in Alzheimer's disease. - Highlights: • Neuron-level, reduction of dendritic complexity in BLA of 9-month-old AD mice. • Specific range of branch decrease in density of 6-month-old AD mice. • 3D imaging with high resolution will provide insights into brain aging.

[en] Identification of gas–liquid flow patterns remains one of the paramount needs in multiphase flow metering. It is hardly possible to realize accurate measurement and control of parameters in a gas–liquid flow system without a clear understanding of its flow pattern. Here we explore the characterization of gas–liquid flow patterns using the norm entropy extracted from the wavelet decomposed pressure fluctuations across a bluff body. Experiments on air–water two-phase flow at ambient temperature and atmospheric pressure are carried out in the bubble, plug, slug and annular flow patterns. On the basis of the experimental results, two original flow-pattern maps are constructed: one is coordinated with the average norm entropy versus the total mass flow rate, and the other is the average norm entropy versus the volumetric void fraction. Verification tests demonstrate that the overall identification rates of the flow-pattern maps developed exceed 95%. This approach provides an effective and simple solution to the classification of gas–liquid flow patterns. (paper)

[en] This monitor can continuously and quickly measure the volume activity of β radioactive aerosol in air. If the result is over a certain threshold, it can alarm automatically. This monitor has a short response time because it samples and measures the radioactive aerosol simultaneously. The control of this monitor is based on 32-bit microprocessor of Motorola Company and uCOS-II embedded operation system. In addition, this monitor provides several communication interfaces to make it easy to control the monitor and acquire the measurement data. (authors)

[en] According to the requirements of the civil environmental γ radiation monitoring, we designed an environmental γ radiation monitor system based on the high pressure ionization chamber and the ultra low current measurement circuit, and tested its dynamic range, temperature coefficient, resolution and reliability. The γ radiation monitor system can work reliably in outdoor environment, and can be used to monitor γ radiation level at both normal and accidental situations. (authors)

[en] Using large area PIN Diodes as detectors, radiation background at interaction region of BEPCI was measured during synchrotron radiation running, beam injection and beam abort, the level, source and characteristic of the radiation background was discussed. The working status of the PIN Diodes installed near IR of BEPCI was studied, which helps the design of the online dose rate monitoring system for BESIII. (authors)