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Recently, design methods based on gm/Id parameters have attracted attention in analog integrated circuit design and have been automated with computer assistance. However, the look-up tables (LUTs) in the gm/Id method have the problem of high hardware resource overhead. To address this issue, this paper proposes a multi-output deep neural network (DNN) structure for modeling the direct-current parameters of transistors and replacing LUTs for circuit design. The proposed DNN models’ performance is verified using mainstream design technologies such as TSMC 40 nm (T40), TSMC 65 nm (T65), TSMC 180 nm (T180), and SMIC 180 nm (S180). Compared with LUTs, the proposed DNN models are able to reduce at least 99.9% storage space occupation and 95.62% prediction time overhead with a mean absolute percentage error of less than 0.2%. In addition, we propose an automated circuit migration design method using DNN models in different technologies, combined with gm/Id parameters. The method generates circuit design databases in different technologies and obtains device design results according to performance requirements. The experimental results show that using DNN models can reduce the time overhead by more than 40% compared to using LUTs. The simulation results of circuit transplantation design show that the circuit performance of T40, T65, S180, and T180 meets the requirements, which verifies the proposed DNN-based automated circuit design method.

Sub-23nm particles emission from the light-duty vehicle is widely discussed now and possible to be counted into the next stage emission legislation, such as Euro7. In this article, 16 China6 gasoline vehicles were tested over the WLTC and two surrogate RDE lab cycles for particulate number (PN) emission, the difference between PN23 (particle size >23nm) and PN10 (particle size>10nm) emission was analyzed. Testing results showed that the average PN10 emission increased 59% compared to PN23, which will bring great challenges for those vehicles to meet the future regulation requirement if sub-23nm particle is counted. The sub-23nm particles emission was proportional to the PN23 particles emission and generated mostly from the cold start or the transient engine conditions with rich combustion. Compared to the proposal of Euro 7, PN10 emission from some tested vehicles will need further two orders of magnitude reduction. With the adoption of an advanced gasoline particulate filter (GPF) sample, the most challenging vehicle achieved the PN10 emission level of 3.3E10 #/km over the surrogate RDE cycle with GPF filtration efficiency above 99% and fulfilled the potential EU7 requirement.

As the official proposal for emission regulation Euro 7 has been released by European Commission, PN above 10nm is taken into consideration for the ultrafine particulate emissions control. The challenges of GPF filtration efficiency emerge for the light-duty manufactures to meet the future emission standards. In the present study, a China 6 compliant vehicle was tested to reveal its performance over the China 6 standards and potential to meet the upcoming Euro 7. Three GPF product types (Gen 1, Gen 2, and concept Gen 3) were mounted to the tested vehicle. WLTC tests were conducted on chassis dynamometer in laboratory as well as a self-designed aggressive cycle (“Base Cycle”) tests. To explore the GPFs performance for PN emissions above 10nm against the proposed limit 6.0E11 #/km, PN emission above 10nm were measured in our laboratory tests for both engine out and tailpipe as well as the PN emission above 23nm. In addition, worst case RDE tests were carried out on the real road with PEMS. It was found that, when including particles down to 10nm, further improvement is needed for the current system, and the Gen 2 and concept Gen 3 products could be a promising path to meet the proposed standards with much higher filtration efficiency. Combined with possibly further extended RDE boundary conditions in Euro 7, the test results suggested that higher filtration efficiency filter products are likely required to comply with the tightened emission regulations.

Isoflavones in soybean seed and root exudates are host-specific signal molecules for Phytophthora sojae to recognize its host, soybean. G protein and calcium signaling pathways are involved in the chemotaxis of zoospores in the recognition of isoflavones. The role played by non-host-specific signaling molecules (sugars and amino acids) found in seed and root exudates on zoospore chemotaxis and mycelial growth was studied. The transcriptome of P. sojae responding to aspartic acid (Asp) and glucose (Glc) was analyzed in parellel by the RNA-seq method. We found that the relative in situ concentrations of amino acids and sugars significantly promoted zoospore chemotaxis, as do isoflavones. Transcriptomics showed that both similarities and differences existed in response mechanisms of P. sojae to Asp and Glc. Asp and Glc activated mitogen-activated protein kinase signaling pathways and the phosphatidylinositol signaling system but not the G-protein signaling pathway, which have been reported to be responsible for zoospore chemotaxis. In addition, ubiquitin-mediated proteolysis and ATP binding cassette transporters were also activated by Asp and Glc. Meanwhile, the glutathione signaling pathway uniquely participated in the response of P. sojae to Asp but was not involved in the response process to Glc, which will be evaluated in another study. Our results provide new insights into the molecular mechanisms of zoospore response to Asp and Glc.

Phytophthora sojae does not infect nonhost maize (Zea mays) but infects nonhost common bean (Phaseolus vulgaris) under inoculation. Soybean seed exudates participate in mediating host resistance to P. sojae before infection. This study aims to elucidate the role of seed exudates in mediating the nonhost resistance of maize and common bean to P. sojae before infection. The behaviors of P. sojae zoospores in response to the seed exudates were determined using an assay chamber and a concave slide. The proteomes of P. sojae zoospores in response to the seed exudates were analyzed with the tandem mass tag method. The key proteins were quantitatively verified by parallel reaction monitoring. Maize seed exudates exerted a repellent effect on zoospores of P. sojae. This result explains why zoospores sense repelling signaling molecules in maize seed exudates that weaken and strongly inhibit chemotaxis signals in the phosphatidylinositol signaling pathway and arachidonic acid metabolism pathway. Common bean seed exudates did not exhibit any attraction to the zoospores because the guanine nucleotide-binding protein signaling pathway, which is responsible for transmitting chemotactic signals, had no significant change. The proteins protecting the cell membrane structure were significantly downregulated, and the early apoptosis signal glutathione was enhanced in zoospores responding to common bean seed exudates, which resulted in dissolution of the cysts. Maize and common bean seed exudates mediate part of the nonhost resistance to P. sojae via different mechanisms before infection. The immunity of maize to P. sojae is caused by the repellent effect of maize seed exudates on zoospores. Common bean seed exudates participate in mediating nonhost resistance by dissolving the cysts.

Friction heat generation of ball screw nut pair may lead to changes in the contact state between ball and raceway. Different contact states may result in a change in the intensity of the heat source of the nut pair, which in turn affects the contact state again until a certain balance is reached. At present, the time-varying research of the heat source of the screw nut pair is mainly carried out from the boundary conditions and the location of the heat source, without considering the influence of the internal structure change of ball screw nut pair. In order to fill this gap, a time-varying thermoelastic coupling analysis method for heat source of screw nut pair is proposed. In this paper, the contact model of ball and raceway is established by the elastic theory of plane strain, and the theoretical solution of the contact point displacement of ball raceway under thermal influence is derived by combining with the thermoelastic theory. Then, through the method of polygon equivalence of ball and raceway profile, the contact angle variation process of ball and raceway under the coupling effect of heat and structure was described geometrically, and the variation rule of heat source intensity was further obtained. In addition, the nut temperature variation rule was obtained through the temperature field experiment of the screw nut pair. The temperature variation curve of the nut pair under heat source induction in the actual working condition was fitted after the temperature drop data and the ambient temperature data were processed. By comparing the theoretical temperature variation curve under constant heat source induction, the heat source variation curve of the nut pair under the actual working condition was finally fitted. The correctness of the thermoelastic theory analysis is further verified. The method proposed in this paper analyzes the variation law of the heat source intensity from both theoretical and experimental perspectives, which has important reference significance for the study of the thermal characteristics of the ball screw system.

Bifacial semitransparent perovskite solar cells (BS-PSCs) have broad application prospects in the field of building-integrated photovoltaics, tandem solar cells as well as transparent chargeable devices. To fabricate high-performance BS-PSCs, the rear transparent electrode is one of the major obstacles should be overcome. Here, we develop a MoOx/Cu/Ag/MoOx multi-stacked electrode by thermal evaporation, and utilize it as a rear transparent electrode in the fabrication of high-performance n-i-p structure BS-PSCs. It is demonstrated that the minimum thickness required to obtain a continuous Ag film is reduced from 15 nm without the seed layer to 10 nm and the optical and electrical properties of multilayer transparent electrode are significantly enhanced. As a result, the BS-PSC device achieves the optimal power conversion efficiency of 13.44% at indium tin oxide side and 10.25% at MoOx/Cu/Ag/MoOx rear transparent electrode side, along with an average 8.67% optical transmittance for the visible light (400–800 nm) simultaneously. This work provides a promising approach to fabricate high-performance semitransparent and bifacial-operable optoelectronic devices in the future.

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In the performance test of a compressor, the overstrain alarm of a rotor blade occurred and it was thought to be caused by a large-sized inlet probe. To explain and further avoid the occurrence of this phenomenon, the influences of probe strut configuration on the vibration strain of the compressor rotor blade and the corresponding flow mechanism are studied by using a one-way fluid-structure coupling calculation method. Firstly, the probe strut is simplified as a cylinder with a diameter of 10 mm and located upstream of the inlet stator with the strut wake impinging on the stator blade according to the compressor test. Then, the three scenarios are considered: moving the strut away from the stator blade in axial direction, shifting the strut half of the stator pitch circumferentially, and reducing the strut diameter. The analysis results show that the characteristics of blade vibration are determined by the excitation force on the rotor blade. Under the interaction between the large-sized strut and the compressor, in addition to the excitation force with the strut passing frequency, a force with a lower frequency, namely, the strut-wake-induced frequency, is also observed. The amplitude of the excitation force on the rotor blade depends on the probe configuration. When one of the excitation force frequencies is close to a natural frequency of the rotor blade, the blade resonates, and the amplitude of blade strain varies with the amplitude of the excitation force. In order to reduce the adverse effect of upstream strut wake on the compressor rotor blade vibration, the inlet probe strut should be designed with a smaller diameter and be placed further upstream of the stator in such a way that the strut wake vortex passes through the midpassage of the following stator.

A facile synergetic strategy is reported for the synthesis of the LiMnO2@VXC-72R composite microspheres by applying spray-drying technique with nanosized LiMnO2 particles as host material and conductive carbon black (VXC-72R) as dispersing agent. In this hybrid structure, LiMnO2 nanoparticles promote the lithium-ion diffusion due to the nanosized diffusion distance, whereas well-distributed VXC-72R suppress the aggregation of LiMnO2 nanoparticles and enhance the electronic conduction. Moreover, the micro-sized spherical morphology with low specific surface area is conducive to reducing the contact area between electrolyte and composite cathode, which inhibit the manganese dissolution. Benefiting from their synergistic effect, the LiMnO2@VXC-72R composite microspheres achieve the maximum discharge capacity of 187.3 mAh g−1 with good cycling stability at 0.1 C. After 50 cycles, the discharge capacity of composite cathode is still maintained at 173.2 mAh g−1, which is significantly higher compared to the primary LiMnO2 particles. Moreover, the LiMnO2@VXC-72R composite microspheres exhibit outstanding rate performance with high discharge capacity.

Differential effects of the seed exudates of susceptible and resistant soybean cultivars Sloan and Williams 82 on the zoospores of soilborne pathogenic Phytophthora sojae are not clear. This study aims to elucidate the role of the seed exudates in the host resistance of soybean against P. sojae during prior to infection. The response behaviors of P. sojae zoospores to the seed exudates were performed in an assay chamber and concave slide, the proteomes of P. sojae zoospores treated with the seed exudates were analyzed by TMT method. The expression of genes encoding key proteins was quantified by qRT-PCR. The zoospores of P. sojae exhibited significant chemotaxis to the both seed exudates and a stronger attracted was found to the seed exudates of Sloan. The seed exudates of Sloan also had a stonger promotion than that of Williams 82 on encystment of zoospores. During the responding process, the key proteins in zoospores related to chemotaxis were upregulated, the upregulation fold of these proteins in responding to Sloan was higher than that of Williams 82. Proteins differentially expressed promote the encystment of zoospores. The changes in expression of these proteins was several fold higher in the zoosprores exposed to the seed exudates of Sloan than that of Williams 82. Evidence of differential changes in protein expression in P. sojae zoospores exposed to the seed exudates of both soybean supports the differential developmental behaviors such as chemotaxis and encystment of the zoospores in responding to the two seed exudates.

It has been reported that the root exudates of nonhost maize inhibit

Gasoline particulate filter (GPF) is a cost-effective solution to particle number emissions from gasoline direct injection vehicles. Filtration efficiency, as a key parameter of GPF, was usually assessed at chassis level over regulatory drive cycles. However, the promulgation of real driving emission (RDE) requirements in the EU and Chinese regulations necessitates evaluations based on non-legislative cycles to guarantee the on-road emissions are compliant to regulatory requirements. In this research, two aggressive drive cycles, RTS95 at 23degC and modified RDE at 0degC, were complemented to the WLTC to evaluate the filtration efficiency of a catalyzed GPF (cGPF) in fresh conditions to obtain the so-called "worst-case" filtration efficiency. In the WLTC, RTS95, and simulated RDE tests, the filtration efficiency of the test cGPF was 51.1%, 41.3%, and 85.1% respectively. In the simulated RDE test, the test cGPF filtrated solid particles with a diameter above 23 nm and 10 nm at a similar efficiency. Increased filtration efficiency with heavier soot load could offset the relatively low filtration efficiency in cold-start and warm-up durations, hence the filtration efficiency for a clean cGPF showed higher sensitivity to cycle length over driving dynamics and testing temperature. In acceleration events with cGPF mounted, the particle diameter where number concentration peaked decreased as the engine warmed up. In deceleration events, bimodal and trimodal particle number size distributions with much lower concentrations were observed.