Supported by Natural Science Foundation Project of Inner Mongolia Autonomous Region (2015MS0324); Scientific Research Service Project of Chifeng University (KYFW-16-05).

1 Introduction

Thymusmongolicus (genus Thymu, family Labiatae) is a perennial aromatic herb and gets name due to strong aroma of its flowers and leaves[1]. There are 12 species of thyme in China, distributed in Inner Mongolia, Gansu, Shaanxi, Qinghai, Ningxia, Xinjiang, Shanxi, Hebei and Beijing[2]. T. mongolicus can be used for medicinal purpose, extracting aromatic oil. Rural people often use it as spice. It has functions of warming the middle and dispelling the cold, removing the wind and relieving pain, resolving phlegm and relieving cough, promoting diuresis and relieving stranguria, strengthening the stomach and inducing perspiration, and regulating stomach. For external application, it can be used for preventing cancer, killing insects, and treating tinea pedis. Studies have shown that T. mongolicus also has the pharmacological effects of treating cancer and improving human immunity[3]. Plants of T. mongolicus are small and aromatic, and can be used as potted plants and flower beds; creeping or large area planting can achieve uniform effect, and they can be used as ornamental lawn and ground cover plants; they are light demanding, drought and barren resistant, strong wind resistant, and can be used for roof greening; they are mainly grown in degraded grassland and have important protection function for ecological environment, and can be used as ecological restoration of ground cover plants[3]. In this study, T. mongolicus from Aohan of Chifeng in Inner Mongolia were used, the volatile components of the flowers and leaves were collected by solid phase microextraction (SPME). GC/MS technique was used to search, analyze and identify specific chemical components[5], to provide the basis for the further development and utilization of T. mongolicus.

生物学概念是思维的细胞，图形是生物学概念的另一种语言，在不同的学段选择适合的生物图进行教学，在帮助学生构建概念、深入理解概念等方面起到了事半功倍的效果。此外，收集经典生物图、自己制作生物图、引导学生构建概念图等也是教学中重要的途径和手段，需要教师不断的积累和学习。

2 Materials and methods

2.1 Instruments and materials Instruments: Agilent 6890N Gas Chromatograph with 5973 Mass Selective Detector (GC-MS) (American Agilent Technologies Co., Ltd.); SPME manual sampling handle and 100 μm poly dimethyl siloxane (PDMS) Extraction Tip (Supleco Company); 5 mL extraction bottle. Materials: flowers and leaves of T. mongolicus were collected from Nianpangou, Anhao, Chifeng City of Inner Monglia Autonomous Region, and identified by Professor Liu Tiezhi from College of Life Sciences of Chifeng University.

2.2 Methods

In the volatile components of flowers of T. mongolicus, 24 kinds of compounds were identified, accounting for 97.187% of the total volatile compounds, mainly terpenes and their oxygen-containing derivatives, aromatic compounds and their derivatives, alkanes and their oxygen-containing derivatives (Table 1). High content compounds include thymol (35.38%), 2-methoxy-4-methyl-1- (1-methylethyl)-benzene (20.022%), 1-methyl-4- (5-methyl-1 -methylene-4-hexenyl) -cyclohexene (12.86%), 1,4-cyclohexadiene (8.793%), 1-methyl-2- (1-methylethyl) -benzene (6.731%), and caryophyllene (6.376%).

In the volatile components of leaves of T. mongolicus, 14 kinds of compounds were identified, accounting for 99.573% of the total volatile compounds, mainly terpenes and their oxygen-containing derivatives, aromatic compounds and their derivatives, alkanes and their oxygen-containing derivatives. Main volatile components include thymol (49.13%), 1-methyl-4- (5-methyl- 1 -methylene- 4-hexenyl) -cyclohexene (6.247%), 2-methoxy-4-methyl-1- (1-methylethyl) -benzene (5.254%), (1R) -1,7,7-trimethyl-bicyclo[2.2.1] heptan-2-one (7.548%), camphene (4.617%), eucalyptol (4.392%), and α-pinene (3.433%). From comparison of volatile components of flowers and leaves of T. mongolicus, it can be seen that there are 10 kinds of the same compounds. Thymol content was highest in the volatile components of flowers and leaves, but thyme content in leaves accounted for 49.13%, which was significantly higher than that in flowers (35.38%), indicating that it may be the main aroma component of T. mongolicus leaves.

2.2.2 Mass spectrometry conditions. Electron impact (EI) ion source; electron energy 70 eV; ion trap temperature 250℃; quadrupole temperature 150℃; mass scan range m/z 35-500[6].

由图1、2、3、4可以看出，53#、18#和48#进路两帮控制较好，49#进路开口处在掘进工程中发生了局部垮帮，故此对开口处进行了素喷支护，支护后再没发生过垮帮现象。1158分段地应力变化情况为两边弱、中间强2，在1#盘区进路集中拉底过程没有发生两帮大面积垮帮现象，经过技术室、质量室和地测室工程技术人员现场的观察认为1#盘区的如发生大面积垮帮现场可以视现场情况进行素喷支护，严重时可以进行单层喷锚网支护。

2.4 Headspace solid phase microextraction (HS-SPME) The extraction tip was inserted into the GC/MS inlet for aging at 250℃ for 2 h. Thirty minutes before the extraction, the flowers and leaves of T. mongolicus were put into 4 mL extraction bottle, and sealed with Teflon-lined silicone rubber pad. The 100 μm PDMS extraction tip was inserted into the samples through the rubber pad of the cap and then the fiber tip was pushed out to avoid touching the samples. The extraction was carried out for 40 min at room temperature (about 25℃), followed by withdrawal of the fiber tip, the extraction tip was pulled out from the sample bottle, then rapidly inserted into GC/MS vaporization chamber, desorbed at 230℃ for 3 min, and started the instrument to collect the data[7].

2.3 Sample processing Samples of mature leaves in upper, middle, and lower position of T. mongolicus plants were taken at 10:00 of sunny day, and samples of flowers were taken in full bloom stage, and samples were taken uniformly in parts of T. mongolicus plants. The solid-phase microextraction device was used for headspace extraction, each treatment was repeated three times and the average value was taken.

3 Results and analyses

在练习中好多学生都看不准在什么时候击球，有时就是太早挥拍导致击不中球。有时就太慢挥拍导致引拍挥拍动作还没有完成就已经击中球了。有时就是没能正中去击中球，击出的球方向偏斜。有时就是击球点靠前，击出的球没有合理抛物线容易被截击。练习方法：先利用固定球练习，用细绳系住羽毛球吊在一定的位置使学生先掌握准确的固定击球点，培养其观察判断能力，再由老师抛球用外界声音提示多次练习形成条件反射，同时加强步法练习。

Fig.1 Total ion chromatogram for volatile components of flowers (A) and leaves (B) ofThymusmongolicus

Table 1 Volatile compounds of flowers and leaves ofThymusmongolicus

No．CompoundsRelativecontent∥%FlowerLeafMolecularweightMolecularformula1α⁃Phellandrene0．321-136C10H162α⁃Pinene∗0．5003．433136C10H163Camphene∗0．1464．617136C10H164Bicyclo[3．1．0]hex⁃2⁃ene，4⁃methyl⁃1⁃(1⁃methylethyl)⁃0．199-136C10H165β⁃Myrcene0．149-136C10H166Mushroomalcohol；1⁃Octen⁃3⁃ol0．097-128C10H16O7Tricyclo[2．2．1．0(2，6)]heptane，1，7，7⁃trimethyl⁃0．937-136C10H168Bicyclo[3．1．0]hex⁃2⁃ene，2⁃methyl⁃5⁃(1⁃methylethyl)⁃0．169-136C10H169(+)⁃4⁃Carene1．289-136C10H1610Benzene，1⁃methyl⁃2⁃(1⁃methylethyl)⁃∗6．7316．858134C10H1411Limonene∗0．301-136C10H16121，3，6⁃Octatriene，3，7⁃dimethyl⁃，(E)⁃0．2810．790136C10H16131，4⁃Cyclohexadiene8．7931．840136C10H1614Bicyclo[2．2．1]heptan⁃2⁃one，1，7，7⁃trimethyl⁃，(1R)⁃-7．548152C10H16O15Eucalyptol；1，8⁃Cineole-4．392154C10H18O16Bicyclo[3．1．0]hexan⁃2⁃ol，2⁃methyl⁃5⁃(1⁃methylethyl)⁃，(1．α，2．β，5．α)⁃0．967-154C10H18O17Borneol∗0．4652．710154C10H18O183⁃Cyclohexen⁃1⁃ol，4⁃methyl⁃1⁃(1⁃methylethyl)⁃0．179-154C10H18O19Thymol35．38049．130150C10H14O20Benzene，2⁃methoxy⁃4⁃methyl⁃1⁃(1⁃methylethyl)⁃∗20．0225．254164C11H16O21Phenol，2⁃methyl⁃5⁃(1⁃methylethyl)⁃0．346-150C10H14O22Cyclohexane，1，5⁃diethenyl⁃3⁃methyl⁃2⁃methylene⁃，(1．α，3．α，5．α)⁃-3．442162C12H1823Caryophyllene6．376-204C15H2424trans⁃α⁃Bergamotene0．206-204C15H24251，6⁃Cyclodecadiene，1⁃methyl⁃5⁃methylene⁃8⁃(1⁃methylethyl)⁃，[s⁃(E，E)]⁃-0．478204C15H2426cis⁃．α⁃Bisabolene∗0．2342．834204C15H2427Cyclohexene，1⁃methyl⁃4⁃(5⁃methyl⁃1⁃methylene⁃4⁃hexenyl)⁃，(S)⁃∗12．8606．247204C15H2428[S⁃(R∗，S∗)]⁃Cyclohexene，3⁃(1，5⁃dimethyl⁃4⁃hexenyl)⁃6⁃methylene⁃，[S⁃(R∗，S∗)]⁃0．239-204C15H24Total97．18799．573

Note: * denotes common compounds of flowers and leaves of T. mongolicus.

2.2.1 Chromatographic conditions. Chromatographic column: HP-5MS elastic quartz capillary column (30 m × 0.25 mm × 0.25 μm); inlet temperature was 230℃; injection mode was splitless injection; carrier gas was high purity helium (99.999%); the constant flow rate was 1.0 mL/min; the temperature programmed work: initial temperature was 50℃, rising to 150℃ at 4℃/min, holding for 2 min and then rising to 250℃ at 8℃/min and holding for 5 min[6].

排水沥青路面作为一种新型路面结构，由于其使用骨架结构且空隙率高达20%～25%，在实际沥青路面施工应用中具有良好的效果。本文通过对掺加不同类型改性剂的排水沥青混合料路用性能进行研究，并结合室内试验提出较为科学的施工工序。希望随着技术发展，铺筑路用性能更优、施工技艺更强、行车舒适性更好的排水沥青路面。

The total ion chromatogram for GC/MS analysis on volatile components of flowers and leaves of T. mongolicus collected by Headspace Solid-Phase Microextraction (SPME) was shown in Fig.1. Analysis was carried out by two-dimensional qualitative method combining mass index search and retention index. From flowers and leaves of T. mongolicus, 24 and 14 kinds of volatile components were identified separately, and relative percentage of volatile components were determined by peak area normalization (Table 1).

4 Conclusions

Volatile components of T. mongolicus were separated by HS-SPME, 24 kinds of compounds were identified by GC-MS, accounting for 97.187% of the total volatile compounds, mainly terpenes and their oxygen-containing derivatives, aromatic compounds and their derivatives, alkanes and their oxygen-containing derivatives.

There are 10 kinds of the same compounds in leaves and flowers of T. mongolicus. The thyme content in leaves accounted for 49.13%, which was significantly higher than that in flowers (35.38%), indicating that it may be the main aroma component of T. mongolicus leaves. Thymol has a strong antibacterial[8-10], anti-oxidation[11-13], and anti-tumor[14] effects, T. mongolicus leaves are suitable for medicinal purposes.

In volatile components of flowers of T. mongolicus, terpenes including 1-methyl-4- (5-methyl-1 -methylene-4-hexenyl) -cyclohexene (12.86%), 1,4-cyclohexadiene (8.793%), and caryophyllene (6.376%) accounting for 28.029%. Terpenes are aromatic and favorable for relieving the nervous emotion[15] and have strong antibacterial, anti-inflammatory and analgesic activities[16]. Thymol and terpenes may be the main aroma components of T. mongolicus flowers. T. mongolicus flowers can be used to extract essential oils, aromatherapy, landscaping and other purposes. Besides, 2-methoxy-4-methyl-1- (1-methylethyl)-benzene accounts for 20.022% of volatile components of T. mongolicus flowers, and its features are to be further studied.

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