扇子的妙用——对农村综合实践活动课的探索

作为一个农民的儿子，我生在农村，长在农村，所以我爱农村；作为一名农村小学的教师，我爱村小的孩子，也为农村教育美好的明天而不懈地努力；作为一名课程资源的开发者，我因地制宜，引导农村的孩子用不起眼的扇子在综合实践活动的课堂中为课程改革开辟出了一片新天地。

Seed Morphology and Seedling Variation of Four Ornamental Lupin Pedigrees

[Objective] This study was conducted to reveal seed characteristics, variation and their effects on seedling growth of ornamental lupins. [Method] The phenotypic characteristics and germination rate of the seeds of four excellent lupin pedigrees were measured, and then their correlations with seeding growth were analyzed. [Result] There were abundant variations among the four ornamental lupin pedigrees. Pink seeds had the largest volume and red seeds had the largest 1 000seed weight. The variation coefficients for the seed morphological traits among the four pedigrees ranged from 2.97% to 14.34%. Seed specific weight and 1 000-seed weight could be used as important indicators for selection in breeding because of their higher variability. Seed weight variation of ornamental lupin was mainly depen- dent on seed width variation. There was small variation in seed length. The seeds of the four ornamental lupin pedigrees started to germinate one day after sowing, and the germination period was 5 d. Germination rate coefficient and germination index of pink and red seeds were higher than those of blue seeds, but blue seeds had the largest germination rate. 1 000-seed weight shared significantly positive correlations with seed germination rate, germination potential and seedling retention rate. Round and large seeds had some advantages in germination. Full seeds had higher germination rate and speed, and seedling retention rate. There was a significant relationship between seed length-width ratio and the number of leaflets of seedlings. [Conclusion] The results provided references for the evaluation of seed phenotypic diversity and breeding research of ornamental lupins.

Relation between basin morphometric features and dynamic characteristics of debris flows——a case study in Siberia, Russia

Extreme and prolonged rainfall in the Tunka Ridge caused several debris flows in the vicinity of the Arshan village(Siberia, Russia) on June 28, 2014. These debris flows, in spite of similar geological conditions, had different velocity, peak discharge and alluvial fan volume values. The flow velocity was from 3.5 m/s to 19.6 m/s, the peak discharge ranged from 63 m3/s to 13566 m3/s, and the alluvial fan volume varied from 4.13×103 to 8.45×105 m3. Such a great range of values is due to the morphometric parameters of the debris flow basins. The article deals with the influence of morphometric parameters of debris flow basins, such as the basin area, the average slope, Melton ratio, relief ratio on the debris flow velocity, peak discharge and volume of alluvial fans. In this debris flow event the average values of slope angle and total basin relief of the debris flow basins did not affect the values of debris flow velocity, peak discharge and alluvial fan volume. The highest correlations were observed with the debris flow basin area that was connected with the water inflow volume into the debris flow basins during the rainfall. The unequal water distribution among debris flow basins also had an impact on the debris flow velocity, peak discharge and volume of alluvial fans.

Automation in detection of recirculation in a booster fan ventilation network

Recirculation is prohibited in many coal mining countries because of the fear that the re-use of return air would allow the build-up of air contaminants at the workings. The incorrect design and location of a booster fan in any ventilation network can create unsafe condition due to recirculation. The current approach to investigating recirculation using simulation software requires manual effort which becomes tedious in a complex and a large network. An algorithm-based C++ program was designed to detect the recirculation in a booster fan ventilation networks. This program needed an input file prepared from output file generated by any ventilation simulator. This program created an output file for recirculation. This program demonstrated the strong capability to detect the recirculation in a sample network and a coal mine ventilation network. The outcomes of this program were documented in this paper.

Characterization, Expression and Function Analysis of DAX1 Gene of Scallop(Chlamys farreri Jones and Preston 1904) During Its Gametogenesis

DAX1, a member of nuclear receptor superfamily, has a function in the sex determination and gonadal differentiation of several vertebrate species. However, little information about DAX1 of invertebrates is available. Here we cloned a homolog of scallop(Chlamys farreri Jones and Preston 1904) dax1, Cf-dax1, and determined its expression characteristics at m RNA and protein levels. The c DNA sequence of Cf-dax1 was 2093 bp in length, including 1404 bp open reading frame(ORF) encoding 467 amino acids. Unlike those of vertebrates, no conserved LXXLL-related motif was found in the putative DNA binding region of Cf-DAX1. Fluorescence in situ hybridization showed that Cf-dax1 located on the short arm of a pair of subtelocentric chromosomes. Tissue distribution analysis using semi-quantitative RT-PCR revealed that Cf-dax1 expressed widely in adult scallop tissues, with the highest expression level found in adductor muscle, moderate level in mantle, gill and testis, and low level in kidney, ovary and hepatopancreas. The result of quantitative real-time PCR indicated that the expression of Cf-dax1 was significantly higher(P<0.05) in testis than in ovary at the same stage, showing a sex-dimorphic expression pattern. Furthermore, immunohistochemical detection found that Cf-DAX1 mainly located in spermatogonia and spermatocytes of testis and in oogonia and oocytes of ovary, implying that DAX1 may involve in gametogenesis of bivalves.

Off-Design Performance Analysis of Axial Flow Fan in Helicopter

A theoretical calculation method of off-design performance is developed for an axial flow fan of oil cooling system in helicopter,including calculation of aerodynamic parameters and performance parameters.When calculating inlet shock loss,the shock loss coefficient is obtained by comparing results of theoretical calculation,experimental and numerical calculation.The theoretical results and numerical results show that all air velocity components increase from hub to shroud in main flow area at rated condition.Tip leakage vortex moves downstream as flow rate increases.When flow rate decreases,Re decreases,and boundary layer thickness from hub to shroud area all increases gradually.Tip leakage vortex moves upstream,and secondary loss increases.Low speed area in the passage is widened along with high speed area moving to hub area,influenced by boundary layer separation.Consequently wake area and jet area at fan outlet are both larger than rated condition.Therefore optimization design for off-design performance of the fan is required on aerodynamic parameters influencing fan loss.A reliable method is supplied for estimating altitude performance of lubricating system in helicopter.

Molecular cloning and characterization of SoxB2 gene from Zhikong scallop Chlamys farreri

The Sox proteins play critical roles during the development of animals, including sex determination and central nervous system development. In this study, the SoxB2 gene was cloned from a mollusk, the Zhikong scallop （Chlamysfarreri）, and characterized with respect to phylogeny and tissue distribution. The full-length cDNA and genomic DNA sequences of C. farreri SoxB2 （CflSoxB2） were obtained by rapid amplification of cDNA ends and genome walking, respectively, using a partial cDNA fragment from the highly conserved DNA-binding domain, i.e., the High Mobility Group （HMG） box. The full-length cDNA sequence of CJSoxB2 was 2 048 bp and encoded 268 amino acids protein. The genomic sequence was 5 551 bp in length with only one exon. Several conserved elements, such as the TATA-box, GC-box, CAAT-box, GATA-box, and Sox/sry-sex/testis-determining and related HMG box factors, were found in the promoter region. Furthermore, real-time quantitative reverse transcription PCR assays were carried out to assess the mRNA expression of CJSoxB2 in different tissues. SoxB2 was highly expressed in the mantle, moderately in the digestive gland and gill, and weakly expressed in the gonad, kidney and adductor muscle. In male and female gonads at different developmental stages of reproduction, the expression levels of CfS;oxB2 were similar. Considering the specific expression and roles of SoxB2 in other animals, in particular vertebrates, and the fact that there are many pallial nerves in the mantle, cerebral ganglia in the digestive gland and gill nerves in gill, we propose a possible essential role in nervous tissue function for SoxB2 in C.farreri.

《刘公案·车王府曲本》俗语词考释四则

本文对鼓词《刘公案·车王府曲本》中四个俗语词“流平、黑打乎、底扇子、眼子”进行考释。“流平”当有两义,一是形容词光滑平整,二是名词指地面。“黑打乎”或写作“黑大糊”“黑的乎”“黑得乎”“黑大/打忽”等,本义是“形容黑色”,曲本《刘公案》中用以比喻不能见光的、违背道德的关系。“底扇子”是指妻子,媳妇,略带贬义色彩。北京话“眼子”一词的义项有两条引申路径:一是“眼睛→孔洞→肛门→整个臀部”;二是“外行,不聪明的人→蠢笨”。据此我们认为该词有三个义项,一是名词指肛门,常代指整个臀部;二是名词外行,不聪明的人,三是由不聪明的人引申为形容词蠢笨。

CYTOLOGICAL COMPARISON OF GAMETOGENESIS OF SCALLOPS,ARGOPECTEN IRRADIANS AND CHLAMYS FARRERI

Histological characteristics of gametogenesis of two kinds of scallops, gonochoric Chinese scallop, Chlamys farreri and hermaphroditic bay scallop, Argopecten irradians were investigated in this study. Spermatogenesis in C. farreri has different developmental stages: spermatogonia, primary spermatocyte, second spermatocyte, spermatid and spermatozoon. A large number of same developmental stage spermatic cells converge at a definite area of the testis. Premeiotic, previtellogenic and vitellogenic oocytes can be found during oogenesis in C. farreri , where oocyte distribution is obviously irregular. The A. irradians gonad consists of two different parts in one individual: one part functions as testis, the other as ovary. Between these two parts is a special appearance area, where a large number of spermatic cells are bound with two layers of acellular substance with many oocytes in it.

In silico prediction of phytoconstituents from Ehretia laevis targeting TNF-αin arthritis

Objective Rheumatoid arthritis(RA)is an autoimmune disease involving the synovial lining of the major joints.Current therapies have noteworthy side effects.Our study involved in silico evaluation of Ehretia laevis(E.laevis)phytoconstituents targeting tumor necrosis factor-α(TNF-α).Methods Molecular docking studies performed to investigate the binding pattern of the plant E.laevis phytoconstituents along with the crystal structure of TNF-α(PDB ID:2 AZ5)using AutoDock Vina followed by a study of interacting amino acid residues and their influence on the inhibitory potentials of the active constituents.Further the pharmacokinetic profile and toxicity screening carried out using Swiss ADME and pk CSM.Results The docked results suggest that lupeol(-9.4 kcal/mol)andα-amyrin(-9.4 kcal/mol)has best affinity towards TNF-αcompared to standard drug thalidomide(-7.4 kcal/mol).The active chemical constituents represents better interaction with the conserved catalytic residues,leading to the inhibition/blockade of the TNF-α-associated signaling pathway in RA.Furthermore,pharmacokinetics and toxicity parameters of these phytochemicals were within acceptable limits according to ADMET studies.Conclusion The binding potential of phytoconstituents targeting TNF-αshowed promising results.Nonetheless,it encourages the traditional use of E.laevis and provides vital information on drug development and clinical treatment.

Temperature Control of a Thermal Plasma Torch with Inductive Coupling Using the Arduino Board

Plasma torch is a device that transforms electrical energy into heat carried by a gas and its safe operation is necessary to control her temperature. This paper presents the use of the Arduino board in temperature control of a plasma torch through fuzzy control. The plasma torch of this project was built so that a flow of water can circulate through your body, allowing its cooling. The cooling system mounted consists of one radiator, one expansion vase, one water pump and one temperature sensor. The heated water coming the plasma torch is passed by the temperature sensor. This is converted in a voltage and read by an analog input port of the Arduino. This processes the information received and makes the decision to turn on/off the radiator fan and/or powered the frequency inverter water pump to control the temperature. The graph of the fuzzy control showed an oscillation between 104 °F to 122 °F around the chosen reference 113 °F. The results show that it is possible to control the temperature of a plasma torch using the Arduino board and fuzzy logic.

扇子

我喜爱扇子。我家里有许多扇子：羽毛扇、大蒲扇、折扇、竹扇……有这么一把折扇是我的最爱。

扇子

奶奶手中韵扇子，画着一只小鸟儿。奶奶扇呀扇，小鸟飞累了。奶奶睡着了，

扇子有清风

扇子有清风，时时在手中，有人向我借，你中我不中——这是静夏季节，乡下的孩子们挂在嘴边的《扇子谣》，单薄的快乐中，透着单薄的狡猾。

扇子案布迷阵

重庆府人胡利，在外做生意很久没有回来。四月的一天，他的妻子一个人在家，晚上被盗贼所杀。那晚天下着小雨，人们在泥里拾到了一把扇子，上面的题词是张林赠给李前的。

Study of Unsteady Flow Simulation of Backward Impeller with Non-uniform Casing

The flow characteristics of the centrifugal fans with different blade outlet angles are basically discussed on steady and unsteady simulations for a rectangular casing fan. The blade outlet angles of the impellers are 35° and 25° respectively. The unsteady flow behavior in the passage of the impeller 35° is quite different from that in the steady flow behavior. The large flow separation occurs in the steady flow field and unsteady flow field of the impeller 35°, the flow distribution in the circumferential direction varies remarkably and the flow separation on the blade occurs only at the back region of the fan; but the steady flow behavior in the impeller 25° is almost consistent with the unsteady flow behavior, the flow distribution of the circumferential direction doesn't vary much and the flow separation on the blade hardly occurs. When the circumferential variation of the flow in the impeller is large, the steady flow simulation is not coincident to the unsteady flow simulation.

Experimental and numerical investigations on convective heat transfer of dual piezoelectric fans

An investigation is performed to study the convective heat transfer performance under dual piezoelectric fans. Three main aspects are involved in the current study. Firstly, vibration tests for dual specific piezoelectric fans actuating at the first-mode resonant frequency are conducted to illustrate the influence roles of vibrating phase difference and fan-to-fan pitch on the piezoelectric fan vibration amplitude. Secondly, heat transfer measurements are made to compare the heat transfer among single fan, dual fans in-phase and dual fans out-of-phase. Thirdly, three-dimensional numerical simulations are conducted to reveal the influence mechanism of dual piezoelectric fans on heat transfer. The results show that, the vibrating phase difference of dual fans has nearly no influence on the displacement velocity and amplitude of piezoelectric fan related to single fan once the dimensionless pitch(P/W) is beyond 1.2. The dual piezoelectric fans produce nearly the same peak heat transfer coefficient as that of single fan case.Of particular is that the dual fans operating in-phase produce more favorable heat transfer than the dual fans operating out-of-phase,especially in the gap zone between dual fans. Due to the interaction between dual fans, the streaming flow induced by one vibrating fan suffers the action of sweeping flow of another vibrating fan when they operate out-of-phase. While for the dual fans operating in-phase, the streaming flows induced by vibrating fans merge together to form stronger wall jet flow in the region between two fans.

Numerical Investigation on the Self-Induced Unsteadiness in Tip Leakage Flow of a Micro-Axial Fan Rotor

The self-induced unsteadiness in tip leakage flow(TLF)of a micro-axial fan rotor is numerically studied by solving Reynolds-averaged Navier-Stokes equations.The micro-axial fan,which is widely used in cooling systems of electronic devices,has a tip clearance of 6%of the axial chord length of the blade.At the design rotation speed,four cases near the peak efficiency point(PEP)with self-induced unsteadiness and four steady cases which have much weaker pressure fluctuations are investigated.Using the"interface"separating the incoming main flow and the TLF defined by Duet al.[1],an explanation based on the propagation of the low energy spot and its multi-passing through the high gradient zone of the relative total pressure,is proposed to clarify the originating mechanism of the unsteadiness.At the operating points near the PEP,the main flow is weaker than the TLF and the interface moves upstream.The low energy spot which propagates along in the close behind of the interface has opportunity to circulate in the circumferential direction and passes through the sensitive interfaces several times,a slight perturbation therefore may be magnified significantly and develops into the self-induced unsteadiness.The explanation is demonstrated by numerical results.

Aerodynamic Characteristic Research on Final Stage Stator of a Highly Loaded Fan

Due to corner separation and other complex three-dimensional flows existing in the highly loaded stator, which influences the fan performance significantly, highly loaded stator blades of a transonic fan with a maximum camber angle of 57° were studied in this paper and sector cascade experiment was adopted. In order to get the stator aerodynamic parameters as realistic as possible and conduct the experiment without the existence of rotor, an adjustable guide vane was designed to simulate the velocity magnitude and direction of the stator inlet flow. Results show that the adjustable guide vane can simulate the rotor outlet velocity direction and magnitude in most span range. The deviation angle is positive and the maximum value is nearly 21° because the severe separation is at 27% span. Corner separation exists on both pressure side and suction side and the location of separation initiation is determined. Finally, the stator blades were redesigned with some suction slots on the suction side. Experiment results show that the suction slots change the flow field structure, increase the capability of flow turning, and decrease the flow loss.

Effect of the Uneven Circumferential Blade Space on the Performance of Small Axial Flow Fan

Effects of the uneven circumferential blade space on static characteristics and aerodynamic noise of a small axial flow fan are studied in this work.The blade angle modulation is adopted to design a series of unequally spaced fans,which have different maximum of modulation angular displacement.The steady flow is simulated by the calculations of Navier-Stokes equations coupled with RNG k-epsilon turbulence model,while the unsteady flow is computed with large eddy simulation.According to theoretical analysis,a fan with a maximum of modulation angular displacement of 6° is regarded as the optimal unequally spaced fan.The experiment of static characteristic is carried out in a standard wind tunnel and the aerodynamic noise of both fans is tested in a semi-anechoic room.Then,performances of the optimal unequally spaced fan are compared with those of the prototype fan.The results show that there is reasonable agreement between the simulation results and the experimental data.It is found that the discrete noise of the optimal unequally spaced fan is lower than that of the prototype fan at the near field monitoring point.This can be explained that the total pressure fluctuation of the optimal unequally spaced fan is much more regular than that of the prototype fan.