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In this paper, we developed a novel conformation generation model, termed SDEGen, learning how a molecule evolves in a stochastic dynamics system starting from noise and eventually relaxing to the conformation that falls into low energy minima.

Proteolysis targeting chimeras (PROTACs), which harness the ubiquitin-proteasome system to selectively induce targeted protein degradation, represent an emerging therapeutic technology with the potential to modulate traditional undruggable targets. Over the past few years, this technology has moved from academia to industry and more than 10 PROTACs have been advanced into clinical trials. However, designing potent PROTACs with desirable drug-like properties still remains a great challenge. Here, we report an updated online database, PROTAC-DB 2.0, which is a repository of structural and experimental data about PROTACs. In this 2nd release, we expanded the number of PROTACs to 3270, which corresponds to a 96% expansion over the first version. Meanwhile, the numbers of warheads (small molecules targeting the proteins of interest), linkers, and E3 ligands (small molecules recruiting E3 ligases) have increased to over 360, 1500 and 80, respectively. In addition, given the importance and the limited number of the crystal target-PROTAC-E3 ternary complex structures, we provide the predicted ternary complex structures for PROTACs with good degradation capability using our PROTAC-Model method. To further facilitate the analysis of PROTAC data, a new filtering strategy based on the E3 ligases is also added. PROTAC-DB 2.0 is available online at http://cadd.zju.edu.cn/protacdb/.

The rational design of chemical entities with desired properties for a specific target is a long-standing challenge in drug design. Generative neural networks have emerged as a powerful approach to sample novel molecules with specific properties, termed as inverse drug design. However, generating molecules with biological activity against certain targets and predefined drug properties still remains challenging. Here, we propose a conditional molecular generation net (CMGN), the backbone of which is a bidirectional and autoregressive transformer. CMGN applies large-scale pretraining for molecular understanding and navigates the chemical space for specified targets by fine-tuning with corresponding datasets. Additionally, fragments and properties were trained to recover molecules to learn the structure–properties relationships. Our model crisscrosses the chemical space for specific targets and properties that control fragment-growth processes. Case studies demonstrated the advantages and utility of our model in fragment-to-lead processes and multi-objective lead optimization. The results presented in this paper illustrate that CMGN has the potential to accelerate the drug discovery process.

Library matching using carbon-13 nuclear magnetic resonance (13C NMR) spectra has been a popular method adopted in compound identification systems. However, the usability of existing approaches has been restricted as enlarging a library containing both a chemical structure and spectrum is a costly and time-consuming process. Therefore, we propose a fundamentally different, novel approach to match 13C NMR spectra directly against a molecular structure library. We develop a cross-modal retrieval between spectrum and structure (CReSS) system using deep contrastive learning, which allows us to search a molecular structure library using the 13C NMR spectrum of a compound. In the test of searching 41,494 13C NMR spectra against a reference structure library containing 10.4 million compounds, CReSS reached a recall@10 accuracy of 91.64% and a processing speed of 0.114 s per query spectrum. When further incorporating a filter with a molecular weight tolerance of 5 Da, CReSS achieved a new remarkable recall@10 of 98.39%. Furthermore, CReSS has potential in detecting scaffolds of novel structures and demonstrates great performance for the task of structural revision. CReSS is built and developed to bridge the gap between 13C NMR spectra and structures and could be generally applicable in compound identification.

With the advent of self-driving cars, vehicular networking is gaining greater attention and the subject of extensive research. It is important to implement a more efficient and secure transportation system by enabling communication among objects on the road. Specifically, safety applications should be delivered in a reliable manner within a limited time period. Several time division multiple access (TDMA) protocols have been proposed to realize this. However, most of the existing research have proposed slot management approaches by taking into account the static topology; they have not sufficiently discussed research on “merging collision” arising from overlapping two or more collision domains due to vehicle mobility. In this study, we examine the effect of merging collision in terms of packet delivery ratio, overhead, and inter-basic safety message (inter-BSM) delay. 1 1 Delay between BSMs received in succession. To mitigate the effect of merging collision, we also propose a lightweight distributed TDMA protocol, where the order of vehicles on the road and their relative distances are exploited to determine the dedicated slot. The collision is further resolved using in-band signaling from the surrounding vehicles. Simulation studies show that the proposed scheme improves the performance of the packet delivery ratio (PDR) 10% more than the comparative protocol, and consequently achieves 97% and 95% PDRs, in highway and urban environment, respectively. Furthermore, the overhead and inter-BSM delay are substantially reduced.

In this paper, K-doped ZnO nanocrystalline powders were prepared by the sol-gel method at 500 °C. The effects of potassium (K) doping on the particle size, phase composition, and light absorption properties of zinc oxide nanocrystals were investigated by X-ray diffraction, transmission electron microscopy and ultraviolet–visible spectroscopy. The main crystalline phase of the powders before and after K doping is wurtzite ZnO. With the increased K doping amount, the purple and blue luminescent peaks are enhanced. The band gap of the sample obtained from the light absorption spectra initially increased with the K doping amount, then decreased, and increased again with the K doping amount, which is consistent with the theoretical calculation results. The calculated energy band and density of states results show that when the K doping amount is small, the band gap is reduced because the K doping forms the impurity level and the conduction band moves downward. This decrease is due to the two impurity levels generated at the bottom of the valence band.

An innovative two-step method perfectly prepared TCLs with different thicknesses, and then the TNA films based on TCLs were successfully prepared. The effects of different thicknesses of TCLs on the morphology and photoelectrochemical performance of TNA films were investigated. The results indicated that TCLs with appropriate thickness could effectively improve the morphology and photoelectrochemical performance of TNA films. Compared with the TNA films based on TCL5, TCL10 and TCL30, the TNA film based on TCL20 exhibited more ideal and comprehensive photoelectrochemical performance. Moreover, dye-sensitized solar cells (DSSCs) based on this TNA film achieved the highest Jsc (10.2054 mA cm−2), Voc (0.5737 V), PCE (3.3%) and Pout (3.31 mW cm−2).

An innovative two-step method perfectly prepared TCLs with different thicknesses, and then the TNA films based on TCLs were successfully prepared. The effects of different thicknesses of TCLs on the morphology and photoelectrochemical performance of TNA films were investigated. The results indicated that TCLs with appropriate thickness could effectively improve the morphology and photoelectrochemical performance of TNA films. Compared with the TNA films based on TCL

CoS2/CNTs composites were prepared by a facile and simple hydrothermal growth of CoS2 in the presence of carbon nanotubes (CNTs), as a novel approach of synthesizing cathode composites for thermal battery fabrication. The incorporation of CNTs in the CoS2 cathode materials thus synthesized effectively improved the electrical conductivity and discharge performance of the resultant cathode, without significantly compromising its thermal stability. The thermal battery cell fabricated with such a composite cathode and with a common Li–Si anode showed all functional features of a proper thermal battery cell. The specific discharge capacity at a cut-off voltage of 1.7 V was 219.8 mA h g−1, and the corresponding energy density was 387.2 W h kg−1. With a pulse current density of 500 mA cm−2, the battery delivered a pulse power of 2.45 W, and maintained 64% of this power after 30 pulses. Regarding thermal stability, the CoS2/CNTs cathode was stable at least at 625 °C.

Active carbon (AC) is modified with nickel oxide (NiO) and inorganic metal oxide (La2NiO4) to synthesize the AC composites using a simple method. The different nanostructures of the obtained AC composites are investigated to achieve high specific capacitance and conductivity. The obtained composites are characterized via scanning electron microscopy, X-ray diffraction, high-resolution transmission electron microscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy. After two-time repeated immersion and heat treatment, the electrode material exhibits an AC-based mesoporous nanostructure. The corresponding resistance of the synthesized AC@NiO composite is 2.55 Ω, which is lower than that of pure AC (5.94 Ω). The CV results are obtained within a stable potential window of −0.9 to 0.9 V in 7 M KOH aqueous solution. The highest specific capacitance of the AC@NiO composite with La2NiO4 is 652.19 F g−1 at the scan rate of 1 mV s−1.

In this work, α-MoO 3 nanoparticles are grown on the surface of nitrogen doped carbon nanotubes (N-CNTs) via a facile electrodeposition method. The morphology of as-prepared nanocomposite shows that the interconnected α-MoO 3 nanoparticles are homogeneously distributed on the surface of N-CNTs. When investigated as a cathode material for lithium ion batteries, the nanocomposite reveals a high reversible discharge capacity of 250 mA h g −1 at a current density of 30 mA g −1 , simultaneously with good cycling performance and excellent rate capability compared with pristine MoO 3 powder. Kinetics of this process is investigated by electrochemical impedance spectroscopy to understand the difference in electrochemical performance and the interface properties between the α-MoO 3 /N-CNTs nanocomposite and pristine MoO 3 powder electrode. The correlation between the unique structural features of α-MoO 3 /N-CNTs nanocomposite and its excellent electrochemical performance is also discussed. The excellent performance makes the as-prepared α-MoO 3 /N-CNTs nanocomposite a promising cathode material for high-performance lithium ion batteries.

TiO2/Bi2S3 composite nanorods arrays were prepared on fluoride-doped tin oxide conductive glass (FTO) by two-step hydrothermal method to adjust the too large band gap of TiO2. The effect of Bi2S3 concentration on the composite film was studied. The crystal structure, surface morphology and photoelectric properties of the composite thin films were characterized by x-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet-visible spectroscopy (UV–vis), fluorescence spectroscopy (PL) and electrochemical workstation. With the increase of Bi2S3 concentration, the absorbance and current density of TiO2/Bi2S3 firstly decreased and then increased, and the transient photocurrent reached 0.16 mA cm−2, which was significantly higher than that of pure TiO2 nanorods (0.017 mA cm−2). The flat band potentials of TiO2 and TiO2/Bi2S3 nanorods were −0.5 V and −1 V, respectively, and both of them are n-type semiconductors.

Physical connection between devices prone to failure in many applications. In the paper, energy coils and data coils are placed independently on the basis of electromagnetic resonant wireless power transmission technology, At the same time , resonant frequency of energy coils and data coils are designed to be the same, energy is one-way transmission from primary side to secondary side, signal can achieve two-way transmission through data coils. Experimental results show that magnetic coupling between energy coils and data coils impacts energy and data transmission slightly in resonance condition and good simultaneous transmission performance can be gained.

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