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The effect of dosage of recycled aggregate from construction waste on the mechanical strength of cement stabilized macadam (CSM) was investigated, the optimal dosage and proportion of recycled aggregate were proposed based on the principle of the highest strength or the maximum dosage. The growth law of mechanical strength of cement stabilized macadam recycled aggregate ( CSMRA) was investigated under the optimal dosage, a prediction model of mechanical strength of CSMRA was proposed, and the reliability of prediction was verified. The results show that the compressive strength of CSMRA increases and then decreases with the increase of recycled fine aggregate dosage, decreases with the increase of recycled coarse aggregate dosage, and the maximum dosage of recycled aggregate is 70% (mass fraction). The correlation coefficient of established mechanical strength growth equation and prediction model is more than 0. 98, and the error between predicted value and measured value is no more than 14. 0%. This indicates that the model can accurately predict the mechanical strength of CSMRA at other ages after determining cement dosage, aggregate type, mineral proportion and 7 d strength. [ABSTRACT FROM AUTHOR]

The conventional petroleum field in Jiyang Depression has always been the main battlefield of exploration and development in Shengli Oilfield. It has experienced more than 60 years of exploration and development and entered the mature exploration stage as a whole， but it still has a relatively large scale of reserve increase every year， which is not consistent with the traditional growth trend of proven petroleum-in-place in oil and gas-bearing basins. The critical issues concerning the exploration decisions of Shengli Oilfield need to be clarified urgently， including the growth law of the conventional proven petroleum-in-place in Jiyang Depression， the strong trend of reserve increase， and the main fields for reserve increase. By analyzing the exploration process of Jiyang Depression， the geological characteristics， resource conditions， exploration investment， theory and technology， resource sequence， and other exploration elements were analyzed， revealing the exploration discovery law of conventional petroleum in Jiyang Depression. The broom-shaped model prediction method and proven rate method of resource were used to predict the growth trend of conventional proven petroleum-in-place. The scale and favorable direction of future reserve increase of conventional petroleum in Jiyang Depression were clarified by analyzing the main fields with reserve increase. The results show that the complex geological characteristics of Jiyang Depression and the relatively abundant remaining resources determine the diversity of exploration objects， the tortuosity of the exploration process， and the long-term nature of exploration history. The conventional petroleum in Jiyang Depression can still maintain a long period of stable reserve increase under conditions of ensuring a relatively stable exploration investment， continuing to innovate the exploration theory and key technologies， and maintaining a relatively reasonable resource sequence. Jiyang Depression can still produce about 2.5 × 108 t of conventional proven petroleum-in-place in the next 10 years under the current economic and technical conditions and the relative guarantee of exploration investment. It is pointed out that the Neogene river sandstone reservoir， lithologic oil and gas reservoirs in the Upper Submember of the 4th Member of the Eocene Shahejie Formation（Es4U）-the Lower 3rd Member of the Eocene Shahejie Formation（Es3L）， and other mature fields are still the ballast stones for stable reserve increase. Kongdian Formation-the deep field of the Lower Submember of the 4th Member of the Eocene Shahejie Formation（Es4L） is an essential field for large-scale reserve increase， and the pre-Paleogene buried hill is a favorable direction for the petroleum enrichment and high yield. In the future， the exploration progress in the unconventional and new energy fields should be closely tracked， and the research results of the growth law and the reserve increase trend of conventional proven petroleum-in-place in Jiyang Depression should be constantly improved and revised to make them more conform to the development trend of oilfield exploration and guide the oilfield exploration decisions.

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Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to systematically study the growth law of Catalpa brmgei and determine its fast - growing period and the optimal growth model, the Catalpa brmgei trees, aged from 18a to 37a, were selected as the research object in Luoning County of Henan Province. The growth data of trees was obtained through stem analysis, and a series of models were applied to fit growth process of tree height, diameter breast height ( DBH ) and volume, and the optimal growth model of Catalpa brmgei was screened. The results showed:

"Planting conifer and reserving broadleaved tree" is an effective way to restore broad-leaved pine forest of temperate zone in Northeast China. Liberation cutting can promote the growth of Korean pine ( Pinus koraiensis ) under forest crown and accelerate the succession. However, how liberation cutting intensity affects the growth of Korean pine in secondary forest is still unclear. Taking the "Planting conifer and reserving broadleaved tree" Korean pine forest in Changbai Mountain as the object, we constructed a growth model of diameter at breast height (DBH) and tree height of Korean pine with double dummy variables (liberation cutting intensity and tree classification) to predict the growth of Korean pine plantation under different liberation cutting intensities, i.e . control (no liberation cutting), light-intensity liberation cutting (retaining upper canopy closure 0.6), medium-intensity liberation cutting (0.4), heavy-intensity liberation cutting (0.2) and clear cutting (cutting all upper broadleaf trees) stands. We analyzed the effects of liberation cutting intensities on DBH, tree height, and the ratio of tree height to DBH. The results showed that among six theoretical growth equations, the Gompertz model on the DBH ( R 2 =0.46) and tree height ( R 2 =0.81) was optimal basic model. The R 2 of the DBH model was increased to 0.65 and 0.89, respectively, after the single dummy variable and the double dummy variable were introduced into the basic model, while the R 2 of the tree height model was increased to 0.84 and 0.94. Therefore, the double dummy variable model was the most suitable for predicting the growth of Korean pine. The growth of DBH of pressed tree increased with the increases of liberation cutting intensity (increase by 145.8%-933.3%) during the whole simulation period (0-80 a). Average and dominant trees showed the same pattern at 42 and 60 a. In the early and middle stages of liberation cutting (20 and 42 a), clear cutting and heavy-intensity liberation cutting had similar effects on the height growth of dominant trees (64.8%-68.5%), average trees (100.0%-144.2%), and pressed trees (138.5%-183.9%). The effects of medium-intensity liberation cutting and light-intensity liberation cutting on the height growth were similar (24.3%-35.1%, 56.0%-92.3%, 84.6%-103.2%). While in the middle and late period (42 and 80 a), height growth of three grade trees increased with the increases of liberation cutting intensity. Under each liberation cutting intensity, the ratio of height to DBH of the dominant, average, and pressed trees increased successively, ranging from 0.50-0.95, 0.64-1.23, and 0.73-4.33, respectively. Only the pressed tree decreased with the increases of liberation cutting intensity at 0-80 a. Therefore, about 40 years after the implementation of liberation cutting, the promoting effect of different liberation cutting intensities on DBH growth was significantly weakened, the promoting effect on tree height growth was significantly enhanced, and the ratio of tree height to diameter began to increase. In order to alleviate forest competition, second liberation cutting should be carried out for light-intensity liberation cutting and medium-intensity liberation cutting stands to further release the growth potential of Korean pine, and thinning management should be carried out in clear cutting and heavy-intensity liberation cutting stands.