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The Lunar Mineralogical Spectrometer (LMS) is one of the main payloads on the Chang’E-5 (CE-5) lunar probe, belonging to the China Lunar Exploration Program. The scientific objective of the LMS is to explore the mineralogical composition and search for evidence of -OH/H2O in the sampling area. The LMS consists of an optomechanism unit, a dustproof calibration unit (DPCU) and an electronic unit. The LMS is installed on the lander about 1.4-m above the lunar surface, the field of view (FOV) is $4.17\times 4.17^{\circ }$ 4.17 × 4.17 ∘ , the instant FOV of the visible imaging channel is 0.28 mrad, and the typical spatial resolution is 0.56 mm/pixel @ 2 m distance. The rotation range of the 2D scanner is $\pm 22.5^{\circ}$ ± 22.5 ∘ along the azimuth axis and $0\sim 30^{\circ }$ 0 ∼ 30 ∘ along the elevation axis, making it possible to observe the sampling area or to select important observing targets. The dispersing beam uses acousto-optic tunable filters, and target detection is performed with a 2D scanner. The LMS acquires spectral imaging information covering 480–950 nm, and reflectance spectra of 900–3,200-nm, both at a 5-nm/band sampling interval. The spectral resolution is $2.4\sim 9.4\text{ nm}$ 2.4 ∼ 9.4 nm in the visible and near-infrared channels and $7.6\sim 24.9\text{ nm}$ 7.6 ∼ 24.9 nm in the short–medium-wave infrared channel. The LMS has a 588-band detection capability designed for fine spectral observation of sampling points and wields a 20-band full-view multi-spectral mode to observe candidate areas prior to sampling. The DPCU of the LMS is integrated with a calibration diffuser that is used for in-flight calibration on the lunar surface using solar irradiation, thus improving the quantitative level of scientific data.

Agricultural Life Cycle Assessment (LCA) is an effective tool for the quantitative evaluation and analysis of agricultural materials production and operation activities in various stages of the agricultural system. Based on the concept of life cycle, it comprehensively summarizes the impact of agriculture on the environment, which is an effective tool to promote the sustainability and green development of agriculture. In recent years, agricultural LCA has been widely used in the agroecosystem for resource and environmental impacts analysis. However, some challenges still exist in agricultural LCA, i.e., the environmental impact assessment index system needs to be improved; its application in different production mode is limited; and combination research with other models needs more attention. This paper discusses the above-mentioned challenges and recommends research priorities for both scientific development and improvements in practical implementation. In summary, further research is needed to construct a regional heterogeneity database and develop innovated methodologies to develop more meaningful functional units for agricultural products to complement LCA by other models. These efforts will make agricultural LCA more robust and effective in environmental impacts assessment to support decision making from individual farm to regional or (inter)national for the sustainable future of agriculture.

Purpose This paper aims to improve the device performance from the perspective of reducing ohmic contact resistance; the effects of different electrode structures and alloying parameters on the series resistance and power-current-voltage of laser diodes (LDs) have been investigated in this paper. Design/methodology/approach Four groups of p-GaAs side metal electrodes with different metal layer arrangements and thicknesses are fabricated for the investigated LDs. The investigated p-GaAs side electrodes are based on Ti/Pt/Au material and the n-GaAs side metal electrodes all have a same structure of Ni/Ge/Ni/Au/Ti/Pt/Au. The LDs with different electrodes were alloyed at 380°C for 60 s and 420°C for 80 s. Findings The experimental results show that the series resistance decreases by 14%–20%, the output power increases by 2%–2.2% and the conversion efficiency increases by 1.69%–2.16% for the LDs prepared with optimized alloying parameters (420°C for 80 s). The laser diode with p-GaAs side Ti/Pt/Au electrode of 30/70/100 nm has the best device characteristics under both annealing conditions. Originality/value The utilization of this improvement on ohmic contact property in electrode is not only very important for upgrading high-power LDs but also helpful for GaAs-based microelectronic devices such as HBT and monolithic microwave integrated circuit.

To meet the demand of the laser application market for semiconductor laser function diversification, this paper proposes a handheld multi-wavelength laser stack packaging module. The 808 nm, 915 nm, and 980 nm semiconductor laser bars are selected for the integrated assembly of the multi-wavelength module. However, with the continuous increase of the optical power density of the integrated packaging module, thermal management has become a key factor affecting the performance and life of the device. In this paper, the finite element analysis method is used to analyze the influence of the arrangement of three laser stripe chips in the stacked packaging structure on the heat dissipation of the multi-wavelength module. The simulation results show that the heat dissipation efficiency of the multi-wavelength module can be improved by 13.74 % by changing the arrangement of chips. A back heat dissipation packaging structure with higher heat dissipation efficiency is proposed, and the influence of chip arrangement and working mode on the thermal characteristics of the device in the new packaging structure is simulated and analyzed. According to the simulation results, a chip arrangement that can make the heat dissipation effect of the multi-wavelength module achieve the best is determined.

As a major agricultural country, the comprehensive accounting of the dynamics and composition of the carbon footprint of major crops in China will provide a decision-making basis for environmental management and agricultural green development in the whole process of the major crop production system in China. To investigate the spatiotemporal dynamics of the carbon footprint for major crops in China, a life cycle-based carbon footprint approach was used to evaluate the carbon footprint per unit area (CFA) and per unit yield (CFY) of eight crops for the period of 1990 to 2019. Our results showed that the CFA for all major crops showed an increasing trend with time before 2016 but slowly decreased afterward, while the CFY decreased by 16–43% over the past 30 years due to the increase in crop yield. The three main grain crops, rice (4871 ± 418 kg CO2-eq · ha−1), wheat (2766 ± 552 kg CO2-eq · ha−1), and maize (2439 ± 530 kg CO2-eq · ha−1), showed the highest carbon footprint and contribution to the total greenhouse gas (GHG) emissions, mainly due to their larger cultivated areas and higher fertilizer application rates. CH4 emission was the major component of the carbon footprint for rice production, accounting for 66% and 48% of the CFA and CFY, respectively, while fertilizer production and usage were the largest components of carbon footprint for dryland crops, making up to 26–49% of the CFA and 26–50% of the CFY for different crops. The present study also highlighted the spatial and temporal patterns of the carbon footprint for major crops in China, which could serve as references for the development of best management practices for different crop production in China, to mitigate agricultural GHG emission and to pursue low-carbon agriculture.

Purpose We performed a novel anatomical and radiological investigation to understand the structure of nasolacrimal duct (NLD) and to provide data to help surgeons locate the openings of NLD efficiently based on landmarks. Materials and methods We examined the NLD region using computed tomography images of 133 individuals and 6 dry skull specimens. Multiplanar reconstruction of the computed tomography images was performed, and the anatomical features of the NLD were studied in the coronal, sagittal, and axial planes. The long and short diameters of NLD were measured along its cross-section. The position of NLD was localized using the nostril, concha nasalis media, and medial orbital corner as landmarks. The free and open source software, 3D Slicer, was used for the segmentation of the NLD and 3D visualization of the superior and inferior openings of the NLD. Results The length, angle, and diameter of NLD were significantly influenced by the age in females compared to those in males. The inferior opening of the NLD could be located efficiently using the nostril and the midsagittal line while the superior opening of NLD could be located using the medial orbital corner. Third, 3D Slicer enabled us to measure the distance between the skin and the bony structure in the image. Conclusion Our study indicates that the sex and age of the patient should be considered while selecting the optimal NLD stent for a patient, and that the precise location of NLD in reference to landmarks can simplify the surgical difficulties and reduce the risk of injury during the transnasal operation.

Introduction The shape of the cavernous segment of the internal carotid artery (CSICA) is various in different people, which makes it difficult to be located and causes a higher possibility of injury in the transsphenoidal approach. Hence, a comprehensive study of the CSICA and a meaningful classification of it are rather helpful to the approach and other operations related to the CSICA. Purpose Our study aimed to make a comprehensive measurement and classify the CSICA into different types so as to better describe its shape and position. Materials and methods Computed tomographic angiography images of 146 internal carotid arteries in individuals (76 males and 70 females) ranging in age from 17 to 78 years (mean, 49.49 y) were reviewed. We measured the distances between the bilateral CSICA at 5 positions in the coronal plane and the angle of the posterior curve segment in the sagittal plane. According to these statistics, we divided the CSICA into different types. Results The distance between the medial walls of the bilateral internal carotid artery is similar to the previous relevant study. We classified the horizontal segment of the CSICA into 5 types: types 1, 2, 3, 4, and 5. Among the individuals we measured, the proportion of each type is 8.2%, 25.3%, 39.7%, 19.9%, and 6.9%. In addition, the posterior curve segment of the CSICA can be classified into 4 types: types Z, A, S, and O. Among the 292 sides we measured, the proportion of each type is 22.6%, 17.8%, 21.9%, and 37.7%. Furthermore, 80.8% of the people with bilateral sides of type O belonged to type 3 and 72.7% of the people with bilateral sides of type Z belonged to type 2. Conclusions The detailed classification of the CSICA is helpful to understand its complexity. The classification of the CSICA can guide the surgeons in the transsphenoidal approach to avoid injuring and to simplify the location of the whole CSICA.

The molecular docking was employed to study the binding of 37 phenyl acetamides derivatives to human α-thrombin. The results showed that hydrogen bonding interactions between Asp189 and basic group of P1 moiety of inhibitors, hydrophobic interactions between Tyr60A, Trp60D and benzene ring of P2 moiety, electrostatic interactions between His215 and negative-charged substituent of the benzene ring, hydrophobic interactions and steric hindrance between the binding site S3 and P3 moiety were the dominant factors affecting the binding affinities. Topomer comparative molecular field analysis (Topomer CoMFA) was then used to establish models for virtual screening, which resulted in a reliable computational model. The number of principal components, r2, q2 (leave-one-out, LOO), r2 pred of the optimal Topomer CoMFA model were 3, 0.869, 0.544 and 0.873, respectively. The results showed that the external predictive abilities of Topomer CoMFA model was much better than that of the traditional CoMFA and CoMSIA models. The structure-activity relationships obtained from Topomer CoMFA model were in agreement with the docking results.