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This is an article in the field of ceramics and composites. To achieve the resource utilization of fly ash and accurately assess the compressive strength of fly ash concrete, three predictive models for compressive strength were constructed using machine learning modeling techniques, including traditional linear regression, decision tree, and support vector machine models. These models were utilized to model and analyze the compressive performance of the concrete. Firstly, a corresponding experimental database was established, with seven input parameters including cement, fly ash, water reducer, coarse aggregate, fine aggregate, water, and curing age, and the compressive strength as the output parameter. Based on 10-fold cross-validation, the performance of the three models on the training set was evaluated using root mean square error (RMSE), mean absolute error, and correlation coefficient, and their performance on the test set was compared. The results showed that curing age had a high correlation with compressive strength (0.60), and the correlation of fly ash with compressive strength was higher than that of cement. The traditional linear regression model exhibited an RMSE of 7.27 and 5.91 on the training and test sets, respectively. The decision tree model showcased an RMSE of 2.72 and 9.23 on the respective sets, while the support vector machine model yielded an RMSE of 5.34 and 4.09. Overall, the support vector machine model exhibited good accuracy and robust performance in predicting the compressive strength of fly ash concrete. This research can provide strength design guidance for concrete using fly ash and promote the resource utilization of fly ash.

The total saline-alkaline land area in China is about 99.13 million hectares distributed across northern China, coastal areas, and areas along the bank of the Huanghe River. About 46 million hectares of saline-alkaline water areas are distributed around these saline-alkaline lands, most of which are thalassic and characterized by a high pH value in excess of 8.8 associated with high-carbonate alkalinity concentrations and various types of ion imbalances. Saline-alkaline waters are stressful environments in which only relatively few organisms are able to survive. Consequently, most of the saline-alkaline water resources have been desolate for a long time. The effective utilization of saline-alkaline water resources will benefit restoration of saline-alkaline habitats and the expansion of aquaculture space. Naked carp (Gymnocypris przewalskii) are endemic to the austere saline-alkaline environment of Qinghai Lake. Due to overfishing in the 1960s and environmental changes in the lake area, the resources necessary for naked carp survival in Qinghai Lake declined substantially. At present, the major measures to protect the naked carp and maintain the ecological balance of Qinghai Lake are through a fishing ban and artificial stocking and releasing. The feeding behavior of fish under natural conditions has obvious rhythm characteristics, which is an important research topic for healthy aquaculture. To explore the characteristics of self-feeding rhythm and growth performance of fish in a saline-alkaline environment and provide basic data for the protection of native saline-alkaline fish, naked carp were taken as representative in this study. First, the freshwater and lake water group with natural photoperiod (14L: 10D) and the lake water group with darkness (24D) were set. The artificial lake water was prepared according to the ionic composition of Qinghai Lake, with the contents of Na+ 23.05%, K+ 1.34%, Ca2+ 0.11%, Mg2+ 6.88%, HCO3– 7.09%, CO32– 5.07%, Cl– 40.39%, and SO42– 16.07%. The measured salinity of the artificial lake water was 15.08, and the carbonate alkalinity was 27.53 mmol/L. According to the local photoperiod of Qinghai Province, the whole day was divided into five periods as 05:00–08:00, 8:00–11:00, 11:00–15:00, 15:00–19:00, and 19:00–05:00. The feeding rhythm experiment lasted for 5 d, and the average food intake of each period was calculated. The results showed that naked carp had an obvious daily feeding rhythm during their natural photoperiod. In the natural photoperiod, the feeding peak was from 08:00 to 11:00, and the low feeding period was from 05:00 to 08:00 in freshwater. In the lake water, naked carp showed high and continuous feeding from 08:00 to 19:00, and their average hourly feed intake was significantly higher than that from 05:00 to 08:00 and 19:00 to 05:00. Therefore, naked carp were determined to be the daytime feeding fish type. In addition, the high proportion and the continuous feeding in daytime in lake water indicated that the osmotic and acid-base regulation of naked carp in saline-alkaline water may enhance their diurnal feeding rhythm. Whereas in the continuous dark environment, the feeding rhythm of naked carp was weakened, and the average hourly food intake of each period was similar. To explore the growth performance of naked carp under a self-feeding rhythm, the lake water group and the freshwater control group with natural photoperiod were set up. After 63 days of self-feeding, the individual body length and weight of the naked carp were measured after being anesthetized with MS-222. The length growth rate (1.19±0.17)%, weight growth rate (10.66±0.98)%, and specific growth rate (0.16±0.02)%/d of naked carp in the lake water group were significantly lower than those in the freshwater group [length growth rate (18.66±0.41)%, weight growth rate (67.32±3.05)%, and specific growth rate (0.82±0.03)%/d)], indicating that the growth of naked carp was inhibited by high salinity and carbonate alkalinity environment. The parameter b of body length-weight relationship curve of the naked carp in both the lake water group and the freshwater group was less than three, which showed that the naked carp was a negative allometric growth fish. The b value of the lake water group was lower than that of the freshwater group, and the body length of naked carp increased faster than body weight in the lake water. The growth characteristics of naked carp were affected by the high saline-alkaline environment. The self-feeding rhythm and growth performance of naked carp provided a basic knowledge for creating a feeding strategy for fish cultured in a saline-alkaline environment and recovering endangered native saline-alkaline fish.

Understanding and mastering the structural characteristics and spatial layout of marine industry, and reasonably guiding the upgrading and spatial layout optimization of marine industry, has great practical significance for Shenzhen in the construction of Global Marine Center City. This paper analyzed the characteristics of marine industry in Shenzhen from 2015 to 2020 by using the methods of centralization index and information entropy, and studied the spatial distribution characteristics of marine GDP and main marine industries in various districts of Shenzhen by using Lorentz curve and nuclear density estimation. The results showed that the marine industry in Shenzhen had a high degree of agglomeration, which was highly concentrated in traditional industries such as marine tourism, marine transportation, marine oil and gas industry, and emerging industries such as marine engineering equipment manufacturing, marine drugs and biological products, marine electronic information and so on. The regional distribution of marine industries was concentrated, and the spatial distribution of main marine industries showed obvious agglomeration. The marine related enterprises were concentrated along the main traffic roads, and their distribution density showed an obvious decreasing trend from coastal to inland. The added value of marine industry in Shenzhen was mainly concentrated in Nanshan, Futian, Bao′an and Luohu, accounting for more than 80% of the city.

In order to explore the characteristics of marine-continental transitional shale reservoir under overburden conditions, studies of organic geochemistry, mineral composition, parameters of pore structure and physical properties of shale in well Y4 of the Upper Permian Longtan Formation in the Puguang exploration area of northeastern Sichuan Basin were carried out. The shale of the Longtan Formation is characterized by high abundance of organic matter (ranging from 3.77% to 10.72%), humic and sapropelic organic matter (kerogen type of Ⅱ2 to Ⅲ) and post stage of maturation (%Ro values ranging from 3.82% to 3.97%). The average pore volume, specific surface area and porosity of shale are 0.047 mL/g, 31.8 m2/g and 6.64%, respectively. Reservoir space is mainly composed of organic pores, interlayer pores of clay minerals, dissolution pores of brittle minerals and micro fractures. The main pore structure is parallel plate-shaped pores and open tubular pores at both ends. The porosity of shale is positively correlated with the contents of TOC, pyrite and quartz in deep-water lagoon environment, which indicated that the original mineral composition and structure were controlled by anoxic reduction and stable water environment. Meanwhile, the effective complexation of rigid mineral particles with organic matter and clay minerals provided necessary conditions for the preservation of organic pores. Reservoir network is consisted of flat organic macropores affected by flattening transformation, densely-developed organic pores, intergranular pores and fractures of brittle minerals, and finally formed ultra-deep shale reservoir deposited in deep-water lagoon microfacies.

In this paper we proposed a knowledge tracing method based on Transformer structure, improved the embedded representation of interactive records, designed a gate unit suitable for this model, and optimized the input processing of self-attention sublayer to improve the predictive performance of deep knowledge tracing model. The experimental results on four commonly used public data sets show that compared with previous methods, the model proposed in this paper can better reflect learners’ mastery of knowledge points, and has better performance on data sets with large sample sizes.

In order to study the influence of solar radiation on temperature field of floating-roof tank, it is necessary to understand the law of temperature changes of crude oil in floating-roof tank under the influence of solar radiation. Based on the analysis of heat exchange of floating-roof tank with the environment, a 3 D model of 2×104 m3 floating-roof tank was established to numerically simulate the temperature changes of crude oil and the tank wall within a day. The results show that under the influence of environmental changes, particularly the solar radiation, high temperature oil layer with large temperature gradient occurs near the wall and the floating tray of the tank, and there is less influence on the temperature of deep crude oil. Combined with the simulation results, a proposal for using the calculation formulas of different tank wall temperature under different conditions with consideration to the solar radiation is offered, so as to reduce the corrected error for volume of floating-roof tank.

The Very Low Frequency (VLF) signal of 10 kHz has strong penetrability of ground objects. Because of the antenna size, its application is limited. Therefore, it is important to study the VLF signal generation method based on appropriately sized high frequency radar antennas. The concept of generating VLF signal with high frequency array antenna is proposed in this paper. The waveform of the emission signal, staggered array structure design, and array parameter selection methods are presented and discussed. The pulse width of the composite signal is increased by using periodic pulse signals as radiation element signals. The resting period of the pulse signals is filled with the pulse width expansion generated by the array and the VLF signal with continuous time is composed in the target area. The performance of the composite VLF signal and the energy utilization of the emission signal are evaluated using Peak SideLobe Ratio (PSLR), Integrated SideLobe Ratio (ISLR) and through the spectrum comparison between the emission signal and the composite signal. With the 10 kHz VLF signal composed by 100 MHz radiant element signals, the hundred meter array is simulated. When the staggered array is constituted by nine arrays and the pulse width of the radiation element is set to 0.115 μs, PSLR and ISLR of the composite signal spectrum are –13.34 dB and –9.44 dB respectively, and the energy proportion of 10 kHz low-frequency signal in the composite signal is 89.79%. The effects of radiation element spacing error, time error, phase error and amplitude error of the radiation element signal and the target’s deviation are analyzed. It is found that the proposed method is an effective one and the simulation results have illustrated the effectiveness.

A combined numerical simulation is conducted to couple fluid flow between exhaust hood and last-stage blades of a 600 MW steam turbine using the computational fluid dynamics software CFX. Based on quadratic orthogonal regression design, the flow guide device at the top of the exhaust hood is installed. The regression orthogonal equation between the installation parameters of the guide plate and the coefficient of static pressure recovery is obtained. The equation is remarkably unlost with nonlinear relation and there is no influence among the three factors. The optimal solution of the regression equation is solved. The channel vortex is broken and the aerodynamic performance of the exhaust hood is improved obviously after the diversion plate is installed. The static pressure recovery coefficient of exhaust hood outlet is increased by 3.008%, the total pressure loss coefficient is reduced by 5.789% and the standard deviation of the outlet is reduced by 3.043. The static pressure recovery coefficient of exhaust hood outlet under different loads after the optimization is always higher than that before the optimization.

To optimal the node deployment of underwater wireless sensor network,a node deployment strategy with multi-metrics based on the grids was proposed.Firstly,the underwater environment was divided into some certain size grids.Then,based on number of nodes,coverage quality of nodes,lifetime of network,network redundancy,a multi-objectives model was proposed.In order to solve the model,cost function with constraint conditions was given.Based on the genetic algorithm,the cost and the energy consumption of the deployment method were computed.The simulation result shows that the energy consumption and the number of deployment nodes are reduced.

The Android mobile terminal’s own identifier information was used,which was credibly ensured by the Android system,then combining the Hash function and operation such as xor or connection,an algorithm of authentication information generation for the Android client was created.The traditional mobile client’s process of register and login were analyzed,putting the identity information generation and authentication on the sever.A novel authentication scheme was constructed,which made the users free from the cumbersome authentication process and privacy divulges.Finally,the security and efficiency of the scheme were analyzed.The results show that the new scheme has strong security and high convenience.

Homomorphic encryption location privacy-preserving scheme based on Markov mode was proposed to solve the problem of location privacy and query privacy protection in location-based service systems. Firstly, the anonymous user's identity were permuted randomly and the Markov state transition matrix combining with the user's historical query content was constructed. Secondly, system previously queries the user's high frequency con-tent and the prediction content under Markov chain, then store the corresponding result sets. Finally, the security of the scheme's double prediction system was analyzed. The scheme makes the LBS receives k+1 query contents which let malicious server or attacker can't determine the corresponding relation between queried user's real identity and queried content. So the user's location privacy and query privacy can be protected. Meanwhile, the computability and confidentiality of homomorphic encryption ciphertext were used to realize the statistical analysis of cipher-text-oriented data and the secure storage of private data.

A provable secure social network privacy-preserving scheme was proposed to solve the problem of social network privacy-preserving scheme's security proof.Firstly,through analyzing the security requirements about the node's privacy (indistinguishable node structure and indistinguishable sending messages),the security model were established separately.Secondly,the bilinear mapping was used to construct the social network privacy-preserving scheme.Finally,it was proved that the scheme was provable secure,the security of the schemes were analyzed and compared.The analysis results show that the scheme not only has provable security,but also can resist re-identify attack,inference attack and information aggregation attack.

The article focuses on a study related to the determination of the genetic relationship between the myostatin (MSTN) gene and chicken growth traits in Bian chicken. Topics discussed include the analysis of single nucleotide polymorphism in exon 1 of the myostatin gene by using polymerase chain reaction–restriction fragment length polymorphism, use of correlation analysis to determine the body weight of chickens, and use of myostatin gene as a genetic marker for growth in Bian chickens.

The temperature of coated workpieces in intermittent grinding with cup wheel is investigated. The effective width of moving heat source is calculated under the condition of plane grinding with cup wheel; the shape of grinding block is simplified in order to use traditional heat source model; triangular and rectangular models are analyzed and compared. Energy partition ratio is analyzed on the basis of actual end-face temperature and one-dimensional heat conduction model, and the energy partition ratio is also obtained under different parameters. The feasibility of the temperature model is verified experimentally, and the influence of grinding parameters on the grinding temperature is also analyzed. The analysis results show that the grinding temperature rises with the increase of grinding depth, work-piece feed speed and wheel linear speed. [ABSTRACT FROM AUTHOR]

To explore the effect of growing altitude on the quality of Zhenghe white tea, the sensory quality and biochemical composition of tea leaves and Zhenghe white tea from different altitudes were evaluated, and multivariate statistical analysis was applied to the obtained data. The results of sensory evaluation showed that there were significant differences in the quality of white tea from different altitudes. The mid- and high-altitude white tea tasted fresh, mellow and clean with a clean and pure aroma, while the low-altitude white tea tasted mellow and thick with a floral aroma. Partial least squares discriminant analysis (PLS-DA) showed that soluble sugars, caffeine, 3-carene, verbenenol, terpene oleene, cis-2-pentenol, 2-ethylfuran and cis-2-hexene-1-alcohol were the key components to distinguish fresh tea leaves from different altitudes. The contents of soluble sugar, cis-2-hexene-1 alcohol and cis-2-pentenol were higher in the mid- and high-altitude samples, while the contents of volatile components such as caffeine, 3-carene, verbenol and terpinolene were higher in the low-altitude samples. Soluble sugar, free amino acid, terpinolene, verbenol, 2-ethyl furan, 2-methylbutyraldehyde, 2-phenylethanol and 3-carene were the key components to distinguish white tea from different altitudes. The contents of soluble sugar and free amino acid were higher in the high-altitude white tea, and the contents of volatile components such as terpinolene, verbenol, phenyl ethanol and 3-carene were higher in the mid- and low-altitude samples, but low in the high-altitude samples. According to odor activity value (OAV) analysis, 2-methyl butyl aldehyde, 3-carene and terpinolene could be used as the characteristic volatile components to identify white tea samples from different altitudes. The results of this study will provide a reference for further exploring the flavor quality of tea from different altitudes.

The underwater target shell has clear technical requirements for the performance of the superhydrophobic microstructure surface coating which has great influences on the navigation resistance of the underwater target. Polyurethane hydrophobic resin and fluorine modified SiO2 particle filler were synthesized according to the synthetic principle of superhydrophobic coating. Three kinds of superhydrophobic microstructure surface coatings including those based on polyurethane hydrophobic resin, silicon - containing resin and fluorine - containing resin were prepared, and the main components and preparation process of each coating were confirmed. Furthermore, the performance of the three superhydrophobic coatings was tested and evaluated, and their performance indicators were compared and analyzed, such as the thickness, hardness, adhesion, static and dynamic hydrophobic angles, surface microstructure, wear resistance, seawater immersion resistance, salt spray resistance and thermal stability. Results showed that the F660 + 8%SiO2 silicone - containing superhydrophobic coating possessed the best comprehensive performance. This would provide a basis for further resistance test of underwater target shell with superhydrophobic microstructure surface coating.

Petroleum exploitation plays a very important role in national energy security. With continuous exploitation of oil fields in my country, the efficiency of conventional water injection oil production is decreasing year by year. Enhanced oil recovery (EOR) technologies, such as polymer flooding, microbial flooding, micro–nano flooding, and other flooding technologies have been proposed and developed for application. However, the microscopic displacement mechanism and displacement effect of these technologies are still unclear. Current oil displacement research needs to be verified by core displacement experiments. However, the current displacement experiments all use artificial cores, glass etching channels, photoetched microchannels, etc., as the oil displacement environment. These displacement environments are insufficient in terms of oil displacement dimensions and observation phenomena. Due to this, there is an urgent need for a core manufacturing method that is more suitable for laboratory oil displacement research. In this study, we proposed a method for manufacturing a simulated three-dimensional core structure based on micro-stereolithography technology. This method not only has the advantages of fast manufacturing speed and high forming accuracy, but is also able to realize the visualization, parameterization, and customized design of a micron structure. The core model self-searched by stereo lithography has a three-dimensional pore structure in the order of hundreds of microns and can be used to simulate the experimental study of reservoir displacement flow mechanism. In this research, a high-precision surface projection micro-stereolithography equipment was built, and the optimal printing process parameters were obtained through a combination of theoretical analysis and experiments. Then, a microsphere stacked core model was proposed that can be used to simulate formation cores. By analyzing the forming mechanism of the core model, a stacking method was selected with a higher forming accuracy to design the core model. Finally, the core of a 100-micron-sized microsphere accumulation was realized by micro-stereolithography to achieve three-dimensional molding. The simulated core manufacturing method in this study has high adaptability to special core structure manufacturing and provides a new idea for studying the microscopic displacement mechanism of various EOR technologies under a laboratory microscope.

An analysis method for the volatile components of squeezed Camellia oleifera seed oil was established by using automatic sample preparation-headspace solid phase microextraction (HS-SPME)combined with gas chromatography-mass spectrometry (GC/MS) technology.The optimum extraction conditions are:Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS) solid-phase microextraction column,extraction temperature 60 ℃,extraction time 50 min,resolution time 5 min,compared with traditional manual water bath extraction method,it has higher total peak area and main peak area; A total of 47 volatile components in pressed camellia seed oil were identified and quantified using this method,of which aldehydes are the main volatile components in camellia seed oil; The characteristic flavor compounds of pressed camellia seed oil obtained by relative odor activity value (ROAV) analysis are 2-hydro-3-hydroxy-4,4-dimethyl-2(3H)furanone,dihydroxy-2(3H)furanone,2-methyl Propionaldehyde,phenylacetaldehyde,nonanal,n-hexanal,trans-2-nonenal,decanal,1-heptanol,3-ethyl-3,5-dimethyl-pyrazine.

Ginger essential oil is the main deep-processed product of ginger. Ginger oil has functional properties, such as anti-oxidation and anti-inflammatory, because of the upgrade of extraction technology.Ginger is widely used in the pharmaceutical and cosmetic industries because of its rich in phenols. Ginger oil not only inherits the function of removing fishy smell, but also retains the health benefits of ginger. With consumers' attention to health, the application of ginger oil in cooking is also concerned. This article compared the advantages and disadvantages of various ginger oil extraction methods, summarized the benefits of ginger oil, and prospected the application of ginger oil based on internal and external R & D and market situation.

Nine chlorogenic acid isomers were extracted from Yunnan Catimor green coffee beans by water-alcohol extraction method. Single factor experiments were carried out to study the material number,ratio of liquid to material, water extraction temperature, extraction time, alcohol concentration and alcohol extraction temperature, and response surface design was used to optimize the water alcohol extraction process. The results showed that the extraction rate of water-alcohol extraction method (5.21%) was significantly higher than that of water extraction method (4.29%)；The alcohol concentration and the ratio of liquid to material had significant influence on the extraction rate of chlorogenic acids (P ≤ 0.01). The optimum extraction conditions of chlorogenic acids isomers by water-alcohol method optimized by single factor and response surface were: alcohol extraction temperature of 60 ℃, extraction time of 11.67 min,material mesh of 60, liquid to material ratio of 16.07, alcohol concentration of 20.16%, the extraction rate of chlorogenic acid isomers were of 5.31%.

To improve the utilization level of rice bran, it is very important to study the accurate separation of key components in rice bran. In this paper, the influence of grinding wheel type, grinding speed and grinding time on the contents of key components in rice bran, such as wax, crude fat and crude protein, was studied, and was characterized and modeled by scanning electron microscopy (SEM), multiple regression analysis and correlation analysis. The results showed that the key components in brown rice were distributed alternately from the outside to the inside, which were wax ester layer, fiber layer, fat-protein layer and starch layer. The highest content of the key components in rice bran and its milling technology combination were of wax 0.67% (860 rpm, 1.0 min), crude fat 18.37% (1 060 rpm, 1.0 min), crude protein 18.59% (960 rpm, 2.0 min), crude fiber 16.85% (760 rpm, 0.5 min) and starch 41.12% (1 060 rpm, 2.5 min), respectively; Grinding wheel type had a very significant impact on wax content and crude fiber content (P

The synergistic antioxidant mechanism of chlorogenic acids (CQAs) was studied in this paper through cyclic voltammograms (CV), oil-water partition coefficient (P), FT-IR, XRD and circular dichroism (CD). The antioxidant capability of CQAs isomers and their mixture was determined by using ABTS free radical quenching ability assay. The results showed that the bigger the antioxidant activity disparity between the CQAs molecules was, the higher the content of high antioxidant activity CQAs was, the better the synergistic effect of the CQAs combination mixture became; The oxidation potential (Epa) of CQAs combination mixture kept constant in the synergistic experiments, which indicted the oxidative coupling interaction don’t exist between the CQAs; The charge transferred (Q) and antioxidant activity exhibited high correlation (0.92); the practical Q was higher than the theoretical Q in the synergistic process and this confirmed that the CQAs (dicaffeoylquinic acids) regeneration of high antioxidant activity happened; the CQAs mixture with the absolute difference value of oil-water partition coefficient of 0.13 gave the good interface effect and high synergistic degree; the interaction and the regular arrangement between the CQAs combination were not discovered through FT-IR, XRD and CD. Therefore, the regeneration mechanism of CQAs molecules and the interface effect of reaction system were the main cause of the phenomenon of the synergistic antioxidant of CQAs.

Based on the established resource populations of Sutai pig, the expression of BPI gene was assayed by Real-time PCR to detect the tissue expression and analyze the differential expression between Escherichia coli F18-resistant and sensitive piglets. This study aimed at providing a theoretical foundation for further research on the role BPI gene in host immunity and resistance to E. coli F18. The results showed that the expression of BPI gene was extremely low or undetectable in tissues including heart, liver, spleen, lung, kidney, stomach, muscle, thymus, and lymph nodes, which was in a stark contrast to the significantly high levels in duodenum and jejunum. In the tissues of both jejunum and duodenum, the mRNA expression of BPI gene in resistant individuals was significant higher than that in the sensitive individuals (Pamp;0.05). The results suggested that BPI gene was likely to be related to the intestinal infection caused by E. coli F18. It is possible that the increased expression of BPI gene in intestinal is in connection with the resistance to E. coli F18.

Ligularia duciformis is a plant of the Ligularia genus (Compositae) which has been reported to have therapeutic effects of treating diseases such as bronchitis and coughing. In order to find out the bioactive components, the 85% ethanol extract of the root and rhizome of L. duciformis was treated by solvents extraction and column chromatography on silica gel and Sephadex LH-20. Six compounds were obtained from the ethyl acetate fraction and identified as 3-methoxy-4-hydroxyphenylpropyl caffeate (I), 6beta, 8beta-dihydroxyeremophil-7 (11)-en-12, 8alpha-olide (II), 6beta, 8alpha-dihydroxyeremophil-7 (11)-en-12, 8beta-olide (III), 6beta-hydroxyeremophil-7 (11)-en-12, 8alpha-olide (IV), stigmasterol (V) and beta-daucosterol (VI) by analysis of their physic-chemical constants and spectral data. Compound I is a new compound and compounds II - V were isolated from L. duciformis for the first time. The antitussive effect of the compounds is under evaluation.