stable isotopes in soil and environmental research

... accepted: 14 April 2016 Published: 06 May 2016 Linking mercury, carbon, and nitrogen stable isotopes in Tibetan biota: Implications for using mercury stable isotopes as source tracers Xiaoyu Xu1, Qianggong Zhang2 ... during feeding experiments, and found no evidence of Hg MIF in either metabolic processes or during trophic transfer, thereby identifying the possibility of tracking sources with Hg isotopes in ... (8.6%) ever in living organisms The δ202Hg and Δ199Hg in sediment and biotic samples increased with trophic positions (δ15N) and %methylmercury Fish total length closely correlated to δ13C and Δ199Hg...

Ngày tải lên: 04/12/2022, 15:04

... (1999) HIV testing and screening Current practicalities and future possibilities In HIV and AIDS, Testing, Screening and ConWdentiality, ed R Bennett and C.A Erin, pp 21–38 Oxford: ... (1999) HIV screening: beneWts and harms to the individual and the community In HIV and AIDS, Testing, Screening and ConWdentiality, ed R Bennett and C.A Erin, pp 61–74 Oxford: ... shared decision-making. Patients should control the amount and timing of information. I submit that in the case of anonymized testing, and in the case of ‘routine’ voluntary named testing, consent...

Ngày tải lên: 01/11/2013, 08:20

... sampling and analysis plan (SAP). Region 9’s guidelines for measuring VOC concentrations in soil and other solid matrices include the following: 1. Samples should be handled as intact soil ... should be handled in intact soil cores and stored in hermetically sealed vessels in both the field and the laboratory. EPA Region 9 Technical Guidelines for Accurately Determining Volatile ... 95-5. Hewitt, A.D. and J.E. Lukash (1996) Obtaining and Transferring Soils for In- Vial Analysis of Volatile Organic Compounds. US Army Cold Regions Research and Engineering Laboratory, Special...

Ngày tải lên: 14/03/2014, 20:20

... Karger, Basel, Switzerland Sinnot 1990 Singletary, G W., Banisadr, R., and Keeling, P L 1994.Heat stress during grain filling in maize: Effects on carbohydrate storage and metabolism Austr J ... distribution in plants and crops Sourcesink relationships Marcel Dekker Inc New York 905 pp Ziegler P 1095 Carbohydrate degradation during germination In “Seed Development and Germination” ( J Kigel and ... Russman, M G Moras D., and Olsen K W 1974 Chemical and biological evolution of a nucleotide-binding protein Nature, 250, 194-199 Rost B and Sander R 1993 Improved prediction of protein secondary structure...

Ngày tải lên: 15/03/2014, 09:20

... floating in water, the moving molecules colliding with the clays and imparting momentum But it was not until 1906, when Einstein developed a theory of molecular collisions to explain the motions and ... discovered geomagnetism and the latitudinal dependence of the magnetic inclination (Fig 1.14) He measured magnetic latitude, ␭, by observing the inclination, I, of compass needles and making an approximation ... Humans in their billions live on, modify, and pollute this delicate interface Silicate and other minerals are weathered by aqueous chemical and biochemical reactions involving atmosphere and biosphere...

Ngày tải lên: 05/08/2014, 13:20

... ocean, expands, and melts The liquid sinks or floats depending upon the density of surrounding seawater Water vapor in a descending air mass condenses and heat is given out to the surrounding atmospheric ... plates and ocean or atmospheric currents is an angular one succinctly summarized using polar coordinates (Fig 2.13c) or in the framework provided by a latitude and longitude grid 2.4.5 Steadiness and ... since all space coordinate systems are entirely arbitrary The important thing is that we think about the differences in the velocity fields witnessed by both stationary and moving observers and...

Ngày tải lên: 05/08/2014, 13:20

... margin, devastating a large area of forest well to the East This happens over and over again Zeus is highly displeased and calls an inquest into the sorry state of Aeolus’s intercontinental wind ... straight line Apparent displacement of p1 at latitude, u, during passage in time, t, of Aeolus's wind = ut (Ω sin u t) = (Ω sin u) ut2 Final target position Initial target position Arc defining motion ... evaluated and strain gradients assessed In homogeneous strain different parameters are used to state the differences in the length of lines and angular changes between lines To determine changes in...

Ngày tải lên: 05/08/2014, 13:20

... when the intensity of the force is maintained, an increment in deformation will occur, defining a strain rate That is why strain rate is used in rheological plots instead of strain as in solids ... be obtained and the shear strain calculated by tracing a normal line to the tangent to the circle at the point where R’ intercepts the circle, and measuring the angle ␺ The shear strain can be ... principles in this way as shown in Fig 4.10 When viscous forces dominate, as say in the flow of liquefied mud or lava, then Re is small and the flow is laminar When inertial forces dominate, as in...

Ngày tải lên: 05/08/2014, 13:20

... in civil engineering, mining, and hazard controls (rock and soil stability in slopes, both natural and constructed) It has been developed over the years by both structural geologists and engineers, ... develop in the plane e1–e2, perpendicular to the direction of maximum lengthening (e1) increment in strain, giving way to further stretching, will provoke a rotation in the cracks due to shearing and ... either linear or nonlinear (parabolic, as in Fig 4.81b) Failure envelopes represent conditions for fracturing for a particular kind of rock and can be constructed joining all points of coordinates...

Ngày tải lên: 05/08/2014, 13:20

... boundary and a magmatic arc in both intra-oceanic and continental active margins Thrust faulting results in crustal shortening and thickening (Fig 4.100c, d) Thrust and fold belts are limited in front ... components a reference line is drawn joining all the inflection points, called the median line, and all the hinge points in both antiforms and synforms, called enveloping lines The wave length is ... folds (the hinge line is always horizontal) and finally, folds having inclined axial surfaces are called steeply, moderately, or gently inclined folds depending on the inclination Inclined folds...

Ngày tải lên: 05/08/2014, 13:20

... reduction in viscosity and melting temperature Also, water has a corrosive effect on Si–O bonds and has a key role in lowering rock melting points (and thus a major role in determining the rheology ... ions and also join to aluminum ions in linked rings The linked groups are said to be in a state of polymerization and are a feature of silicate melts It is the continuous, polymer-like, linkage ... confining pressure on rock strength, reducing it to the effective stress sufficient to cause rupture or runaway strain Therefore in a stressed rock, rather than remaining in situ as increasingly...

Ngày tải lên: 05/08/2014, 13:20

... turbulent mixing and therefore cooling due to momentum and heat transport in the dynamic models In addition to their obvious role in increasing wind shear and forward momentum transport in associated ... of estimates of surface wind shear lies in its key role in determining coupled ocean–atmosphere interactions, especially their role in determining surface flow direction in climate models For this ... mean climate for particular regions and a net global balance between incoming and outgoing radiation, yet looking back through recorded history and into the young and then older geological record,...

Ngày tải lên: 05/08/2014, 13:20

... Labrador and Greeenland seas, the latter due to wind shear by the Irminger tip jet (Fig 6.30), and by more local shear producing mixing gyres, as in the mistral wind in the West Mediterranean and ... Thermohaline currents are linked to compensatory intermediate and shallow warmer currents in a complicated pattern of downwelling and upwelling, whose detailed paths in the Pacific and Indian Oceans ... 0.02–2.0 m and heights from a few millimeters to m (Figs 6.69 and 6.70) Wavelength increases linearly with increasing grain size and with flow strength Ripple migration and growth from random irregularities...

Ngày tải lên: 05/08/2014, 13:20

... mechanical, including photocopying, microfilming, and recording, or by any information storage and retrieval system, without permission in writing from the publisher. Current printing (last ... nucleic acids. Growth promoting substances. such as auxin, gibberellin, and vitamins are included in the latter group, and their biotic origin and decomposition are examined in relation to claims ... book starts by examining the concepts of humus and humic matter from the two different standpoints. Definitions are given in Chapter 1 to delineate soil organic matter, humus, and humified substances....

Ngày tải lên: 11/08/2014, 12:21

... soluble in water, (2) ulmic acid and humic acid, the brown and black fraction, respectively, soluble in alkali but insoluble in acid, and (3) ulmin and humin, the fractions insoluble in alkali, ... triggered in the beginning a flurry of investigations and the ligno-protein theory was introduced during this period by a number of people (Fuchs, 1930a, b, c; 1931; Hobson and Page, 1932a, ... considerable attention in Germany. By using neutral salt solutions, Springer (1938) succeeded in separating humic acid into a (1) brown fraction (Braunhuminsaure), soluble in NaC1, and (2) gray...

Ngày tải lên: 11/08/2014, 12:21

... (High Funtioning Autism – HFA) thuật ngữ dùng để nhóm trẻ RLPTK có số thông minh từ trung bình trở lên, đối lập với HFA tự kỉ chức thấp (Low Funtioning Autism – LFA) với số thông minh trung bình ... Hoàng Gia Anh (Institute of Psychiatry, King's College London), dẫn đến kiểm tra mặt sinh học đơn giản cho tự kỉ trình chẩn đoán kỳ vọng rõ ràng hết Bộ não người tự kỉ có khác biệt tinh vi so với ... xử lí thông tin cụ thể (Frith, 2003; Sigman, Dissanayake, Arbelle & Ruskin, 1997) Khó khăn nhận thức thường xuất trước yêu cầu đòi hỏi xử lí thông tin trừu tượng chuỗi kiện thông tin mang nghĩa...

Ngày tải lên: 26/12/2013, 11:11

... sinh xung phong nhiều trả lời ý: ngày khai trường nước Việt nam Dân chủ Cộng hòa Giáo viên gợi ý để học sinh khai thác thêm thông tin học sinh trả lời không trúng Điều hoàn toàn có lý thông tin ... nhiệm kiến thiết đất nước? Câu hỏi học sinh trả lời tốt thông tin 38 không hiển rõ nét mà yêu cầu học sinh phải suy luận chút phải gắn thông tin với nhau: Học sinh phải cố gắng siêng học tập, ngoan ... lời câu hỏi tìm hiểu nội dung đọc Bài Thư gửi học sinh Sau học sinh đọc nối tiếp đoạn vài học sinh đọc toàn bài, giáo viên bắt đầu cho học sinh làm việc theo nhóm để trả lời câu hỏi tìm hiểu...

Ngày tải lên: 17/03/2014, 19:32

... Sn Tinh ó em y l vt n trc v c ún a dõu v 38 Thy Tinh n sau, khụng ly c M Nng, ựng ựng ni gin, em quõn ui ỏnh Sn Tinh.Thy Tinh hụ ma, gi giú, dõng nc sụng lờn cun cun Nh ca rung ũng chỡm bin nc ... ụng ginh c mt h bc Tuy vy ụng rt bun vỡ cu trai li bing Mt hụm, ụng bo : - Cha mun trc nhm mt thy kim ni bỏt cm Con hóy i lm v mang tin v õy ! B m s vt v, lin dỳi cho mt ớt tin Anh ny cm tin i ... tr v a cho cha Ngi cha vt nm tin xung ao Thy thn nhiờn, ụng nghiờm ging : - õy khụng phi tin lm Ngi li i B m ch dỏm cho ớt tin n ng n ht tin, nh tỡm vo mt lng xin xay thúc thuờ Xay mt thỳng thúc...

Ngày tải lên: 05/04/2014, 19:42

... lô gic, đập tan gông cùm lí trí, đạo đức, tôn giáo tin cậy trực giác, giấc mơ, ảo giác, linh cảm tiên tri - Dựa theo lý thuyết “tự động tâm linh” Brơ tông họ kêu gọi hướng tới hồn nhiên không ... thơ Đọc thơ, suy cho cách tiếp cận kinh nghiệm sống, tiếp cận giá trị tinh thần nhà thơ sáng tạo nên Nhưng nhà thơ phải sống thời đại cụ thể, không gian tinh thần cụ thể Vì thế, thơ họ, mặt, ... số phận khái quát nêu lên vấn đề nhân sinh có tính tổng quát “Chiếc thuyền xa” Nguyễn Minh Châu tác phẩm có phối hợp điểm nhìn Với truyện ngắn này, Nguyễn Minh Châu khám phá người phức hợp, đa...

Ngày tải lên: 28/05/2014, 10:01

... giống nhau, tự nhiên vốn sẵn có mà phải qua trình hình thành bồi dưỡng Nhất em học sinh Với học sinh lớp - học sinh tốt nghiệp THCS - trước ngã rẽ đời (các em tiếp tục học lên bước sang hướng khác ... văn cho học sinh thông qua dạy - học đọc - hiểu văn thơ trữ tình” Với phạm vi hạn hẹp tiết dạy thơ đại cho đối tượng học sinh hai lớp 9B, 9C trường THCS Tuân Đạo; trình tích luỹ kinh nghiệm ngắn ... cảm mình, đọc mẫu cho học sinh đoạn thơ đầu: “Một bếp lửa chờn vờn ……… sống mũi cay”, sau hướng dẫn học sinh đọc đọc tiếp trình phân tích Kết hợp đọc thầy, đọc trò, học sinh có cảm nhận bước đầu...

Ngày tải lên: 02/06/2014, 15:42