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Due to the excellent physical properties and advantages in the field of tumor therapy, lutetium 177 has attracted extensive attention in the field of internal radiation therapy in nuclear medicine. The carrier free radionuclide lutetium 177 can be used for targeted treatment of neuroendocrine tumor and prostate tumor. The carrier free radionuclide lutetium 177 can be prepared by irradiating high abundance ytterbium 176 isotope in reactor. The experimental study result found that the abundance of ytterbium 176 isotope directly affects the activity of lutetium 177. In order to meet the requirement of high abundance of ytterbium 176 isotope, in view of the characteristics of high primary separation coefficient and good universality of electromagnetic method, the key process parameters of electromagnetic separation and preparation of high abundance ytterbium 176 isotopes were studied. Ultra dry YbCl3 with purity of 99.99% was selected as the separation raw material according to the requirements of electromagnetic isotope separation on raw materials. The trajectory of ytterbium ion beam in magnetic field was simulated, and the effects of magnetic induction intensity and beam opening angle on the dispersion of ytterbium isotope separation were given. The results are the same as the theoretical analysis. The design of nonuniform field will increase the dispersion between isotopes, reduce the sputtering contamination between isotopes, and then improve the abundance of isotopes. The emission angle of ytterbium ion beam is 11°, the seven isotopes of ytterbium can be separated completely, and the dispersion of ytterbium 176 and ytterbium 174 is large. The effects of ion source parameter on the beam intensity and focusing ability of ytterbium isotopes were obtained by ytterbium isotope electromagnetic separation experiment. The main basis for judging whether the discharge parameters of the ion source are appropriate is the current intensity of the ytterbium 176 ion beam and the focusing ability Q of the ion beam. In this experiment, the ratio of the current intensity of the ytterbium 176 to the panel current intensity was taken as the embodiment of the focusing ability Q. This experiment was carried out by controlling the variable method, and the optimal combination of separation parameters was given. Finally, ytterbium 176 isotope sample with high abundance was prepared by electromagnetic separation. After separation, the ytterbium isotope in the receiver is chemically purified to obtain ytterbium 176 isotope, which is detected by mass spectrometer. The abundance of the sample reaches 9816%. The high abundance ytterbium 176 isotope prepared in this study is chemically treated to form Yb2O3 compound, which is used as the target of nuclear reactor irradiation to supply the demander.

In mineral, environmental, and engineering explorations, we frequently encounter geological bodies with varied sizes, depths, and conductivity contrasts with surround rocks and try to interpret them with single survey data. The conventional three-dimensional (3-D) inversions significantly rely on the size of the grids, which should be smaller than the smallest geological target to achieve a good recovery to anomalous electric conductivity. However, this will create a large amount of unknowns to be solved and cost significant time and memory. In this paper, we present a multi-scale (MS) stochastic inversion scheme based on shearlet transform for airborne electromagnetic (AEM) data. The shearlet possesses the features of multi-direction and multi-scale, allowing it to effectively characterize the underground conductivity distribution in the transformed domain. To address the practical implementation of the method, we use a compressed sensing method in the forward modeling and sensitivity calculation, and employ a preconditioner that accounts for both the sampling rate and gradient noise to achieve a fast stochastic 3-D inversion. By gradually updating the coefficients from the coarse to fine scales, we obtain the multi-scale information on the underground electric conductivity. The synthetic data inversion shows that the proposed MS method can better recover multiple geological bodies with different sizes and depths with less time consumption. Finally, we conduct 3-D inversions of a field dataset acquired from Byneset, Norway. The results show very good agreement with the geological information. [ABSTRACT FROM AUTHOR]

A time‐domain finite‐element method based on an arbitrary quadrilateral mesh is proposed to simulate two dimensional seismoelectric and electroseismic waves in SHTE mode. By decoupling the electrokinetic coupling equation, we can solve seismic waves and electromagnetic waves independently. For the simulation of seismic wavefield, we utilize a more compact second‐order unsplit perfectly matched layer that is easier to implement in finite‐element methods. Moreover, to avoid errors caused by the quasi‐static approximation, we directly solve the full‐wave electromagnetic equations when simulating the electromagnetic wavefield. Our computational domain is discretized using arbitrary quadrilateral meshes, which offers possibilities in handling undulating terrain and complex anomalies in the underground. To ensure computational accuracy, we utilized biquadratic interpolation as our finite‐element basis functions, which provides higher precision compared to bilinear interpolation. We validate our time‐domain finite‐element method by comparing its results with analytical solutions for a layered model. We also apply our algorithm to the modelling of an underground aquifer and a complex anomalous hydrocarbon reservoir under undulating terrain. [ABSTRACT FROM AUTHOR]

Ytterbium isotopes have important applications in radiopharmaceuticals, atomic clocks, nuclear physics and other fields. Electromagnetic method is the best choice for the separation of ytterbium isotopes. In order to collect and monitor the ytterbium isotopes separated by electromagnetic method, a ytterbium isotope beam receiving and monitoring system is developed. According to the characteristics of ytterbium isotope separation, such as small dispersion, large number and difficult separation, a modular collector with multi slit panel and built-in water cooling structure and a beam monitoring system were designed through theoretical calculation and empirical parameters. The evaporation and sputtering of isotopes were reduced and the abundance of ytterbium isotopes was improved. Finally, the test of ytterbium isotope beam receiving and monitoring system was completed. At present, the system has been applied to the separation of ytterbium isotopes, and the ytterbium 176 isotope abundance has reached 96.9%.

Aerogels present a huge potential for removing organic dyes from printing and dyeing wastewater (PDW). However, the preparation of aerogels with multiple dye adsorption capabilities remains a challenge, as many existing aerogels are limited to adsorbing only a single type of dye. Herein, a composite aerogel (CG/T‐rGO) with the addition of carboxymethyl chitosan, gelatin and tannic acid reduced graphene oxide (T‐rGO) was synthesized by freeze‐drying technology. The electrostatic interactions between dye molecular and GEL/CMCS (CG) networks, as well as the supramolecular interactions (H‐bonds, electrostatic interactions and π–π stacks) between T‐rGO, have endowed the aerogel with the ability to adsorb multiple types of dye, such as methylene blue (MB) and methyl orange (MO). Results exhibited that the prepared CG/T‐rGO aerogel possessed strong mechanical strength and a porous 3D network structure with a porosity of 96.33 %. Using MB and MO as adsorbates, the adsorption capacity (88.2 mg/g and 66.6 mg/g, respectively) and the mechanism of the CG/T‐rGO aerogel were investigated. The adsorption processes of aerogel for MB and MO were shown to follow the pseudo‐second‐order kinetic model and Langmuir isotherm model, indicating the chemical adsorption of a monolayer. The proposed aerogel in this work has promising prospects for dye removal from PDW. [ABSTRACT FROM AUTHOR]

In recent years, the thermochromic hydrogel was acted as suitable sandwiching material to adjust light transmission. However, to accurately control the thermochromic temperature in a wide range still was a significant challenge. Here, a simple method was explored to prepare hydrogels with gradient opaque‐transparent transition thermochromic temperature from 5 °C to 53 °C, which was regulated by the aggregation state of sodium dodecyl sulfate micelles by adding potassium tartrate hemihydrate and cations. Using Li+, Na+, and K+ as cations, the accuracy was controlled at 1 °C. Moreover, the transmittance of the hydrogel was not changed when the thermochromic temperature was adjusted. As a result, an intelligent window was fabricated by utilizing thermochromic hydrogel as a sandwiching layer into the outer glass layers, which could effectively and stably regulate the visible and infrared light. The temperature monitors/detectors were also designed, which showed excellent temperature monitoring/detecting ability. Therefore, this low‐cost, high‐efficient, large‐scale prepared thermochromic hydrogel provided more potential for intelligent temperature devices. [ABSTRACT FROM AUTHOR]