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Located on the western flank of the Changbai Mountains in Northeast China, Hani (HN) peatland has been studied intensively for Holocene paleoclimate reconstruction on decadal to centennial scales. This study presented new datasets of hydroclimatic controls on the distribution and abundance of mosses through modern vegetation survey and plant macrofossil analysis of a historical peat profile. Survey on the abundance of ten different moss species in 40 vegetation quadrats and their depths to water table (DWT) in the HN mire have been conducted during the growing season (June to October) in 2015 and 2016. Our results indicated that (1) the abundances of these mosses showed close relationship with DWTs; and (2) DWT was a function of local precipitation with lower DWT corresponding to higher precipitation. Sphagnum fallax, S. cuspidatum and S. subsecundum preferred wet microhabitats under higher precipitation (i.e., lower DWT), and vice versa. Hence, the variation in the abundance of these sphagna was considered to be an indicator of changes in precipitation. An equation for quantitative estimation of DWT based on the abundances of the moss species along different moisture habitats has been established based on the modern survey, which was able to reconstruct the variation of DWT in the past from plant macrofossil analysis. A 50 cm core from HN mire was dated by AMS 14C, 210Pb, and 137Cs methods, providing a 50-year record of hydroclimate. Plant macrofossils were identified at 1 cm intervals of the peat core, which exhibited detailed variations of the moss assemblages. The variation of DWT reconstructed from the coverage of S. fallax and the total coverage of S. fallax, S. cuspidatum and S. subsecundum in the core matched well in peak-to-peak and trough-to-trough with local growing season precipitation on annual scale during the past 50 years. Our study suggests that selecting well-responsive Sphagnum species is a key factor to reconstruct hydroclimate by using plant macrofossils.

In this work, six isosteviolamino acid conjugates were designed and synthesized through simple condensation on a large scale without protecting group (Scheme). These amphiphilic organocatalysts mediated asymmetric three-component Mannich reactions of cyclohexanone and anilines with aromatic aldehydes in the presence of H2O. Meanwhile, the isosteviolproline conjugate 3b has been established as a highly efficient catalyst (Table 1), and afforded syn-Mannich products with excellent diastereoselectivities (syn/anti up to 98 : 2) and enantioselectivities (up to >99% ee; Table 3). The transition state of the reaction in the presence of H2O is proposed (Fig. 2).

A new structure of mechanical pulse CVT –rotational swash plate pulse CVT was put forward. This paper analyzed the impact of helical gear parameters on swash plate pulse CVT characteristics, it can be seen that the angular velocity of output shaft is proportional to the angle between Swash plate surface and vertical cross section of the input shaft and the swash plate surface, the gear modulus has no effect on the transmission ratio, the guide rod pitch diameter is the major factor contacting gear tooth Strength, when the other parameters unchanged, ( is the pitch helix angle)is proportional to the output torque, and is inversely proportional to the output torque.

This paper began with the theory of laser-distance measurement and the composition of the flatness detection system, and mainly analyzed the error of the flatness measurement system of hot rolling strip caused by the installation and studied the maximum thickness which could be allowed to measure in order to ensure the measurement precision

An extract from the female sex gland of Semiothisa cinerearia attracted conspecific males in field tests. A major active component was isolated from the extract and identified by GC-MS, GC-IR and microchemical reactions as cis-3,4-epoxy-(Z,Z)-6. 9-heptadecadiene, which showed strong EAG response. Another minor yet important component was identified as (Z,Z,Z)-3,6,9-heptadecatriene.

A versatile neutral metalloligand [Cu(PySal)2] (1) (PySal = 3-pyridylmethylsalicylidene-imino) was exploited as a building unit to construct five complexes {Cu[Cu(PySal)2]2}(ClO4)2 (2), {Cd[Cu(PySal)2]2(H2O)2]} (NO3)2 · 2H2O · 4CH3OH (3), {Zn[μ2-Cu(PySal)2]Cl2}n · nCH3OH (4), {Hg[μ2-Cu(PySal)2]I2}n (5) and {Cd[μ2-Cu(PySal)2]Cl2}n · nCH2Cl2 (6). [Cu(PySal)2] acts as a chelating ligand in discrete complexes 2 and 3 with unbound anions, but as a bis-monodentate bridging ligand in polymers 4, 5 and 6 when halogen anions coordinated cooperatively to metal cations. The coordination geometry of Cu2+ is well-defined square planar in bridging [Cu(PySal)2], analogous to that in free metalloligand (1), but it is distorted square planar in chelating [Cu(PySal)2].

Functional magnetic resonance imaging (fMRI) has been widely used in the research of acupuncture mechanism in recent years. This article analyzes the effect of four main influencing factors, i.e., research subject, selection of acupoints, manipulation of acupuncture and evaluation of Deqi, and examples are given to explain research application of these four aspects. Based on those mentioned above, the authors presumed that removing ex terior and interior factors of research subject, optimizing compatibility of acupoints and manipulations of acupuncture and making use of correct evaluation scale of Deqi can improve the scientificity and objectivity of fMRI for evaluation of acupuncture mechanism research.

Among the conjugates tested, IPC is found to show good activity and stereoselectivity for the reaction of anilines, aromatic aldehydes and cyclohexanone.

Generation of an intramolecularly tethered, nonracemic diaryl cuprate followed by its oxidation with ground state oxygen at −78° leads to a biaryl precursor to an ellagitannin. Subsequent attachment of the appropriate glucose unit completes the synthesis of the title compound.

Generation of an intramolecularly tethered, nonracemic diaryl cuprate followed by its oxidation with ground state oxygen at −78° leads to a biaryl precursor to an ellagitannin. Subsequent attachment of the appropriate glucose unit completes the synthesis of the title compound.

Triphenylphosphoniomethanide and alkyl-substituted analogs are torsionally unrestricted even at -100 Deg whereas the temp. dependence of the rotation around the Ca, Ph axis in triphenylphosphoniophenylmethanide reveals this ylide to be resonance stabilized to the extent of 8.5 kcal/mol. [on SciFinder (R)]

The NMR signals exhibited by the ipso-carbon atoms of a variety of phenylated phosphorus compds., e.g., Ph5P, were found to span over the remarkably wide range of +162 to +117 ppm. Nevertheless, these changes in chem. shifts have little diagnostic value. They are tentatively attributed to a charge-mediated contraction and expansion of the C,P s-bond orbital on one hand and to a s-bond induced deformation of the arom. p-electron cloud on the other. [on SciFinder (R)]