Publications by authors named "Jianpei Zhang"

Three new cadinane sesquiterpenes (-) and three known sesquiterpenes were isolated from the stems and branches of A. C. Smith.

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Fifteen unreported prenylated C-C derivatives (1-15) were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith, including one bis-prenylated C-C derivative (1), three prenylated C-C derivative-shikimic acid ester hybrids (2-4) and 11 prenylated C-C monomers (5-15).

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The connection between users in social networks can be maintained for a certain period of time, and the static network structure formed provides the basic conditions for various kinds of research, especially for discovering customer groups that can generate great influence, which is important for product promotion, epidemic prevention and control, and public opinion supervision, etc. However, the computational process of influence maximization ignores the timeliness of interaction behaviors among users, the screened target users cannot diffuse information well, and the time complexity of relying on greedy rules to handle the influence maximization problem is high. Therefore, this paper analyzes the influence of the interaction between nodes in dynamic social networks on information dissemination, extends the classical independent cascade model to a dynamic social network dissemination model based on effective links, and proposes a two-stage influence maximization solution algorithm (Outdegree Effective Link-OEL) based on node degree and effective links to enhance the efficiency of problem solving.

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Rice cultivation in cold regions of China is mainly distributed in Heilongjiang Province, where the growing season of rice is susceptible to low temperature and cold damage. Choosing and planting rice varieties with suitable GD according to the accumulated temperate zone is an important measure to prevent low temperature and cold damage. However, the traditional identification method of rice GD requires lots of field investigations, which are time consuming and susceptible to environmental interference.

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Support vector machine (SVM) is a robust machine learning method and is widely used in classification. However, the traditional SVM training methods may reveal personal privacy when the training data contains sensitive information. In the training process of SVMs, working set selection is a vital step for the sequential minimal optimization-type decomposition methods.

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Three seco-prezizaane-type sesquiterpene lactones, one phenylpropanoid, and two lignans were isolated from the 95% ethanol extract of stems and branches of Illicium ternstroemioides with silica gel column chromatography, ODS column chromatography, and preparative HPLC. Based on the spectral data, they were identified as burmanicumolide D(1), veranisatin A(2), veranisatin B(3), dihydroconiferylalcohol(4), pinoresinol(5),(-)-matairesinol(6), respectively. Among them, compound 1 was a new seco-prezizaane-type sesquiterpene lactone, and 2-6 were obtained from this plant for the first time.

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Nitrogenization is an effective method for improving the capacitive deionization (CDI) performance of porous carbon materials. In particular, polymer organic frameworks with heteroatom doping, containing an ordered pore structure and excellent electrochemical stability, are ideal precursors for carbon materials for high-performance CDI. In this study, a nitrogen-enriched micro-mesoporous carbon (NMC) electrode was fabricated by carbonizing a Schiff base network-1 at 500, 600, and 700 °C.

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Thirteen compounds were isolated from the lipid-soluble extracts of Illicium ternstroemioides A. C. Smith, including eleven previously undescribed prenylated C-C compounds, a previously undescribed prenylated C-C derivative-abscisic acid ester hybrid, and a known compound (4S)-illicinone I.

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Illihenin A (), a novel sesquiterpenoid, was isolated from the roots of . The structure was determined by spectroscopic analyses, ECD calculation, and single-crystal X-ray diffraction. Compound represents a class of novel 5/7/6 tricyclic sesquiterpenoids featuring a rare cage-like tricyclo[6.

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Ion-exchange polymer and modified carbonization bacterial cellulose (CBC) electrodes were fabricated using varying amounts of cation-exchange polymers (glutaric acid (GA) and sulfosuccinic acid (SSA)) and assembled within an asymmetric capacitive deionization unit (p-CDI). The performance of selective NO electro-adsorption was studied. The AC/CBC-SSA group showed a better salt adsorption capacity (14.

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Ten undescribed highly oxidized sesquiterpenes and six known sesquiterpenes were isolated from HO-soluble part of the fruits of Illicium lanceolatum A. C. Smith.

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Ten seco-prezizaane sesquiterpenes were isolated from the water-soluble fraction of the fruit of Illicium lanceolatum using the combined methods of silica gel column chromatography,Sephadex LH-20 column chromatography,and RP-preparative HPLC. They were elucidated as majusanol E( 1),2α-hydroxycycloparviflorolide( 2),2β-hydroxy-3,6-dedioxypseudoanisatin( 3),majusanol A( 4),merrillianone( 5),cycloparvifloralone( 6),3α-hydroxycycloparvifloralone( 7),1,2-dehydrocycloparvifloralone( 8),henrylactone C( 9),and( 11) 7,14-ortholactone-3α-hydroxyfloridanolide( 10) according to the NMR data. All compounds were obtained from this plant for the first time.

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As an ideal miniaturized light source, wavelength-tunable nanolasers capable of emitting a wide spectrum stimulate intense interests for on-chip optoelectronics, optical communications, and spectroscopy. However, realization of such devices remains a major challenge because of extreme difficulties in achieving continuously reversibly tunable gain media and high quality (Q)-factor resonators on the nanoscale simultaneously. Here, exploiting single bandgap-graded CdSSe NWs and a Fabry-Pérot/whispering gallery mode (FP/WGM) coupling cavity, a free-standing fiber-integrated reversibly wavelength-tunable nanolaser covering a 42 nm wide spectrum at room temperature with high stability and reproducibility is demonstrated.

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Five new compounds (1-5), including three hexalactone derivatives (1-3) and a pair of new oxaspiro-carbon epimeric glycosides (4 and 5), and six known compounds (6-11) were obtained from the fruits of Illicium lanceolatum. The structures of the new compounds were elucidated using extensive spectroscopic data. The absolute configurations of compounds 1-3 were determined by an analysis of their CD spectra.

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Sentiment analysis is widely studied to extract opinions from user generated content (UGC), and various methods have been proposed in recent literature. However, these methods are likely to introduce sentiment bias, and the classification results tend to be positive or negative, especially for the lexicon-based sentiment classification methods. The existence of sentiment bias leads to poor performance of sentiment analysis.

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A new collaborative filtered recommendation strategy was proposed for existing privacy and security issues in location services. In this strategy, every user establishes his/her own position profiles according to their daily position data, which is preprocessed using a density clustering method. Then, density prioritization was used to choose similar user groups as service request responders and the neighboring users in the chosen groups recommended appropriate location services using a collaborative filter recommendation algorithm.

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Analyzing massive user-generated microblogs is very crucial in many fields, attracting many researchers to study. However, it is very challenging to process such noisy and short microblogs. Most prior works only use texts to identify sentiment polarity and assume that microblogs are independent and identically distributed, which ignore microblogs are networked data.

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In the existing centralized location services system structure, the server is easily attracted and be the communication bottleneck. It caused the disclosure of users' location. For this, we presented a new distributed collaborative recommendation strategy that is based on the distributed system.

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In this paper, we consider the problem of reconstructing the temporal and spatial profile of some physical phenomena monitored by large-scale Wireless Sensor Networks (WSNs) in an energy efficient manner. Compressive sensing is one of the popular choices to reduce the energy consumption of the data collection in WSNs. The existing solutions only consider sparsity of sensors' data from either temporal or spatial dimensions.

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It is important to cluster heterogeneous information networks. A fast clustering algorithm based on an approximate commute time embedding for heterogeneous information networks with a star network schema is proposed in this paper by utilizing the sparsity of heterogeneous information networks. First, a heterogeneous information network is transformed into multiple compatible bipartite graphs from the compatible point of view.

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Finding the true source of a social network is a crucial component of social network information tracing. Using the new media microblog as an example, this paper provides a source tracing algorithm ITEPE (Initiators and Early Participants Extraction) to solve this problem. First, the cascade (session tree) is built according to the retweeting of a microblog, after which the cascade set (session forest) is clustered by topical relevance.

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Since traditional mobile recommendation systems have difficulty in acquiring complete and accurate user information in mobile networks, the accuracy of recommendation is not high. In order to solve this problem, this paper proposes a novel mobile recommendation algorithm based on link community detection (MRLD). MRLD executes link label diffusion algorithm and maximal extended modularity (EQ) of greedy search to obtain the link community structure, and overlapping nodes belonging analysis (ONBA) is adopted to adjust the overlapping nodes in order to get the more accurate community structure.

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