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An efficient strategy for the preparation of trifluoromethylated dihydroisoquinolinones visible-light induced radical cyclization of -allylbenzamides with CF SO Na was developed., A green and efficient strategy for the preparation of trifluoromethylated dihydroisoquinolinones visible-light-induced radical cyclization of -allylbenzamides with CF SO Na in water at room temperature was developed. This photoinduced reaction generated the desired products in good to excellent yields under simple and mild conditions.

Air pollution is still a big problem in China, and research on PM2.5 related issues is still a hot topic. Based on the data of Changsha City from 2016.01-2018.04, this paper uses Genetic algorithm optimization BP neural network to construct the evolutionary model of PM2.5 in Changsha. The validity, versatility and reliability of the model are verified by comparison with actual data.

In recent years there has been a growing interest in Internet of Thing, Big Data and Mobile Internet. With the rapid growth of the amount of data in the embedded environment, using a traditional embedded processor is hard to satisfy the requirements of big data processing. Sorting is one of the fundamental operation in data processing and is also frequently used for search, filter, feature analysis and so on. It can contribute significantly to the overall execution time in a system. Existing techniques accelerate sorting using multiprocessor or GPUs, but it is impractical for embedded systems. In this paper, we propose a FPGA-based collaborative hardware sorting unit for embedded data processing. The waiting data is transferred from the embedded processor to our hardware sorting unit by the data bus, then a ordered sequence is given form hardware sorting unit and is returned to the embedded processor by data bus. The waiting data is processed in a pure hardware circuit, do not need anything software operation, so the calculating speed depends on the delay time of hardware circuit, which is faster than traditional iterative algorithm by software method. By the collaborative hardware unit, we can greatly reduce the processor load and improve the operation efficiency significantly. In addition, we can define the size of the data bit flexibly, we can also expend the scale of the unit by circuit topology.

Kako je moguće predvidjeti taloženje visokih zgrada i analizirati pomak temelja kako bi se zaštitile podzemne komunalije? To je urgentan problem u današnjoj izgradnji. U svrhu njegovog rješenja, u ovom se radu istražuje kako piloti utječu na vrijednost pomaka temelja primjenom Mohr-Coulomb Modela i 3D računarskog programa FLAC3D s 20 m dubokim iskopima temelja kao primjerom. Analiza pokazuje da je distribucijski uzorak pomaka temelja bez pilota konveksna krivulja, a da s pilotima krivulja postaje valovita uz porast vrijednosti pomaka temelja za 0,4÷0,6. Isto tako parametri poput udaljenosti pilota, promjera pilota i njihove dužine utječu na tu vrijednost na način da veći razmak snižava ograničenje pilota na vrijednost pomaka temelja. Stoga se u radu predlaže da najveći razmak između pilota ne bi trebao biti veći od 6d kad je ograničeni iznos vrijednosti oko 0,23÷0,37. Povećanje promjera i dužine pilota (ne više od 1,25 puta dubine kopanja) može učinkovito ograničiti pomak. Prema tome, u radu se daju korisni parametri za konstrukciju pilota, dokazuje njihovo djelovanje na mehanizam za ograničenje pomaka temelja i pruža analitička osnova za optimizaciju pilota., How can people predict the sedimentation of tall buildings and analyze the foundation rebound to protect underground utilities? This is the urgent problem in today's construction. To solve it, this paper is dedicated to analyzing how piles affect the foundation rebound value by using Mohr-Coulomb Model and the 3D emulation calculation software FLAC3D with 20-meter-deep foundation pits as an example. The study shows that the distribution pattern of the foundation rebound without piles is a convex curve while piles make the curve go corrugated with the foundation rebound value shrieking by 0,4÷0,6. Also, parameters such as the distance of the piles and diameter of the piles and length of the piles have an effect on the value in a way that the increasing distance lowers the piles' restriction on the foundation rebound value. Therefore, this paper suggests that the largest distance between piles should be no more than 6d when the restricted extent of the value is about 0,23÷0,37. Raising the diameter and length of the piles (no more than 1,25 times of the digging depth) can restrict rebound effectively. Therefore, this paper concludes useful parameters in pile design, proves its mechanism for restriction on foundation rebound, and provides analytical basis for optimization of the piles.

Cast austenitic stainless steel (CASS) is widely used in important engineering components, which has a two-phase microstructure, i.e.austenite and ferrite. With slow cooling rate during solidification procedure, the austenite grain is coarse and the morphology of ferrite is complex. Due to the remarkable elasticity anisotropy of austenite, the resulting structural noise makes the recognition of macroscopic defects quite difficult in ultrasonic testing. To improve the signal-to-noise ratio, the ultrasonic testing frequency is generally small, about 0.5-2.0 MHz, and the ultrasonic scattering effect of ferrite is ignored. However, for submillimeter or even smaller defect and damage near the surface, the ultrasonic testing frequency should be increased to achieve a higher resolution. In these cases, how the ferrite influences the ultrasonic wave propagation behavior and the testing result is still not conclusive. Therefore, CASS Z3CN20-09M is studied as an example in this paper. Based on ultrasonic propagation modeling and “in situ” experimental design, the crystal orientation relationship between ferrite and austenite in CASS is studied and the factors influencing the ultrasonic scattering attenuation are clarified. The results would be helpful for clarifying the ultrasonic response mechanism of CASS and critical for the quantitative evaluation of small defects and early-stage damage.The orientation relationship between ferrite and austenite and its influence on ultrasonic scattering attenuation in CASS are studied. The crystal orientations and their relationships between two phases are characterized by the EBSD technique. A two-dimension anisotropic model is built based on the morphology of ferrite, and the ultrasonic propagation is calculated by the time domain finite difference method. The influences of orientation relationship and morphology on the longitudinal wave attenuation are analyzed and verified by “in-situ” experiments. Results show that ferrite grains with bar or island shape are distributed on the austenite grains. The orientation relationship between ferrite and austenite is mainly Kurdjumov-Sachs relationship, and only a minority of ferrite and austenite satisfy the Nishiyama-Wassermann relationship. Numerical simulation of the ultrasonic propagation under a testing frequency of 15 MHz indicates that the orientation relationships between two phases and ferrite morphologies present collaborative effects on the ultrasonic scattering attenuation, which could not be ignored. The factors influencing the ultrasonic attenuation in austenite grain are quantitatively analyzed. It is found that in single austenite grains of CASS, the inhomogeneity of crystal orientation, the orientation relationship between austenite and ferrite and the ferrite morphology play an important role in determining the total ultrasonic attenuation.The results would provide supports for clarifying the ultrasonic response mechanism of CASS and developing the quantitative evaluation methods.